Against All Oddsby Matt Hagny

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Alan Mindemanndefied the odds tobootstrap his farminto existence overthe last 9 years,daring on a differ-ent course from the outset: No-tillwith diverse rotations. Utterly goingagainst southwest Oklahoma’s con-formist mentality of monoculturewheat with grazing and massivetillage, Alan had to fend off plentyof criticism. Not to mention he prac-tically had to invent a functional no-till system for his region.

Alan did, in fact, grow up on awheat & cattle operation north ofLawton, Oklahoma, and today cus-tom farms cropland for his dad andbrother. But the path from then tillnow is not exactly what you mightguess. It’s more like traveling fromWichita to Oklahoma City via LosAngeles—and on foot.

As a young lad, Alan found themechanical aspect of farm machin-ery fascinating, and farming ran inhis blood. But no opportunity was tobe had for a livelihood on hisfather’s farm. Alan instead held an

March 2005 • Volume 4 • Number 1

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ContentsAgainst All Odds .....................209

Maximize Crop Residues ........214

Soil Regeneration ....................220

Controlled Traffic ...................227

Grace Under Pressure ............230Mindemann’s foray into cotton production paid off in ’04.

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eclectic series of jobs over the years,including working on a drilling rig,as a diesel mechanic, and with theCivil Service. After one particularlyunpleasant work experience, hedecided what he really wanted to dowas farm—Damn the torpedoes!Alan set about the task with virtuallyno savings, no equity, and little sup-port from family. If the received wis-dom was that it couldn’t be done,Alan paid it no heed.

What Alan did have was consider-able inquisitiveness and a good busi-ness sense. In his own words, hisfarm operation used no-till from theoutset because he had no choice—

Editors:Matt Hagny Andy HolzwarthRoger LongRandy SchwartzKeith Thompson

E-mail: editor.leading.edge@notill.org

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——— V ———No-Till on the Plains Inc’s Mission: To assist agricultural producers inimplementing economically, agro-nomically, and environmentallysound crop production systems.Objective: To increase the adoptionof cropping systems that willenhance economic potential, soiland water quality, and quality of lifewhile reducing crop productionrisks.

a story on no-till involving an Allis“no-till planter.” Alan thought elimi-nating tillage was a great idea, sincehe really didn’t enjoy those boyhoodhours on a tractor doing tillage onhis father’s farm. Although his dadsaid no-till wouldn’t work there,Alan eagerly read any of the spo-radic articles in the farm magazinespertaining to no-till. When he gotserious about starting to farm in ’96,with no-till, he learned all he couldfrom the scant few farmers in theregion doing no-till, mostly from theOklahoma Pioneers of No-tillAssociation centered around Enid,and in particular a farmer nearEnid, Bill Carpenter. But they were 100 miles to the north ofMindemann, and wide-eyed newbies at that.

Today, Mindemann crops 800acres—mostly rented, but also arecent purchase—plus managinganother 3200 acres. ‘Managing’means he is paid a flat fee for han-dling the input decisions, scoutingthe fields, etc. On those acres he isalso paid a flat fee for any fieldoperations he performs, and heseeds all of those acres with hismachinery. Another neighbor owns ahigh-capacity sprayer, and contractswith Mindemann to do all the spray-ing on the acres under his manage-

ment. Mindemann ownsthe chemical supply, how-ever, which allows him toshop extensively for gooddeals; he also providesthe liability insurance.Cotton and wheat har-vesting are hired,although Mindemannowns an old 6620 com-bine for harvesting othergrain crops and seedwheat.

Alan doesn’t stop there;he finds many other waysto market his skills andgenerate cash flow.Despite not having a for-

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he couldn’t afford all the steel andfield operations associated withtillage. “No-till was the only way Icould start farming.” He rented atractor, and bought a 750 drill—thefirst one sold in his area back in ’96(several years later, his 1560 was thesecond one). Alan hired what hecould, and traded out work withneighbors. Nor could he afford sig-nificant mistakes—“I started farm-ing knowing my first mistake wasalso going to be my last.” As inbankruptcy.

What in the world made this jack-of-all-trades think he could be success-ful when most of the other farmersin his region were failing? Andwhere did he get the idea to no-till,and the knowledge to make it work?Mindemann admits to being “an avidreader.” One soon realizes that hehas the determination to track downthe answers he needs—whether it bespending the time in the field inves-tigating, or contacting the experts.He seems to have a knack for ferret-ing out important bits of obscureinformation, for finding opportuni-ties, and for conjuring up his ownsolution when the need arises.

Mindemann was “always fascinatedwith no-till”—his imaginationsparked at age 14 or 15 after reading

Alan examines his wheat for aphids and disease.

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Perhaps the grasslands of Ft.Sill to the south help, and hedoes admit to only puttingcorn on his better soils, but hisfavorable record in the face ofdrought is still remarkable.

Alan’s latest big adventure wasgrowing significant cottonacreage in ’04—with amazingresults. Alan had grown upwith cotton, and a fair amountwas still being planted in his area,but the idea of growing that cropwith his own money and labor wasquite distasteful. The dry winter of’02/03 was pushing him that direc-tion, along with other factors, suchas the area’s progress with the bollweevil eradication program. Hemade his calculated guess, and wentfor it.

Nearly all of the 2004 cotton intilled fields in Mindemann’s areamade 450 lbs/a or less—“That’sabout half of what we made. Thedifference was management.” This isa simple statement of fact, not someego-trip. Alan explains themethodology for

most cotton production in the area:“They do their tillage, plant it withsome worn-out drill or planter, nofertilizer, and then show up with astripper after it freezes.” Lendingcredence to the story, Alan laternotes that county ‘T’ yields for cot-ton are so low that it is pointless forhim to insure cotton.

When Alan decided to try his handat cotton, he was going to do it right.He utilized the advice of BryceKing, longtime cotton expert withHelena, to get him up to speed.Alan himself describes hawking overhis cotton fields, watching carefullyand trying to learn. It paid off, with

mal education in agronomy,Mindemann is a Certified CropAdvisor and a ‘for-hire’ consultanton outside acres. He offers varioustypes of management arrangements,including handling FSA and NRCSpaperwork. He contracts with thecounty to spray roadside ditches. Aman in motion.

King of Crop Diversity

Mindemann’s cropping system con-tinues to evolve as opportunitiesemerge or fade. He once grewsesame in the rotation, although ithas been omitted for the last 3 yearsdue to the poor market. At first heharvested the sesame only for grain,but then discovered the hay hadvalue: “Sesame is a natural nemato-cide. The ‘organic’ gardeners like itfor this reason. . . . Sesame [hay] isprobably the most lucrative thingI’ve ever done. But I was supplyingthe world market, and some of myproduction is still in storage in theirwarehouse.”

Mindemann again is bucking theconventional wisdom by plantingcorn 3 out of the last 4 years. In anarea where it wasn’t supposed towork, he has averaged 82 bu/a overthose 3 years, and all of those wereaverage or below-average for precip-itation, often so during criticalmonths for corn. “All three werelousy corn years [for weather]. Ihaven’t yet seen what we can do in agood year.” Alan also supplies thefact that he’s never had a load ofcorn rejected for aflatoxin, despitemuch of his corn going to dairieswith strict requirements. He notesthat milo seems even more likely tofail than corn in his area, due to thelong dry summer months—hedoesn’t plant any.

Mindemann’s success with corn is alittle surprising, given the dry years,poor soils, and southerly location. Atan elevation of only 1200 feet, thenights aren’t exactly cool either.

lint yields ranging from 668 to 968lbs/a. His practices include planting35,000 to 40,000 seeds/a in 30-inchrows with his 12-row JD 1760planter (an ’04 purchase for Alan),and applying the necessary fertiliz-ers. In ’04, he applied Orthene in-furrow for thrips, sprayed all thefields again for thrips (bad year),again for fleahoppers, and oncemore for bollworms on the non-Btcotton (again, bad year). All the cot-ton had one application of Pix, andwas defoliated in September. Hisonly major change for ’05 will be touse Cruiser seed treatment to helpon thrips control. After scrutinizingthe growth and fruiting patterns in’04, he became even more con-vinced of the need for uniform seedspacing and emergence, causing himto rebuild his planter for ’05 withthe inclusion of Pro-Shaft (‘cable’)drives to smooth the meters.

Wheat rounds out Mindemann’srotation. Alan sometimes grazeswheat (which he leases to hisbrother for that purpose), but con-trary to the way nearly all wheat inthat part of the world is managed,Alan specifies: “We almost never dodual-purpose wheat—for both graz-ing and grain. It’s so hard to get itright [for both]. It’s either all for for-age or all for grain.” Because of thetime-crunch of trying to get lots ofacres in with a 15-foot drill, plus thewet fall of ’04, quite a bit of Alan’swheat went in with a Phillips rollingharrow. While not such an unusualpractice for his area with mild win-ters, Alan says, “It’s not my pre-

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“The difference was management.”

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Alan’s stacked wheat following a sudan cover crop.

ferred method. The stands are unre-liable [non-uniform emergence tim-ing].” He doesn’t plan to use theharrow much anymore, with hisrecent purchase of a 30-foot 1890air drill.

Alan’s basic rotation is 2 or 3 yearsof wheat, then striving for 2 yearsaway from wheat—“I’d really like tobe out of wheat for four years.” Henotes that the 2d-year wheat is oftenbetter than the first, and 3d-yearwheat is the lowest-yielding and hasthe most weeds and other problems.He is now using a Greenseeker tohelp ‘dial-in’ the N rates for hiswheat (with the help of high-N cali-bration strips), explaining it oftengives him the confidence to go withlower rates than he otherwise might.Alan’s rotation is in continual flux,and this year he will likely growsome spring oats for seed to capturea locally high market. Winter canolaalso intrigues him.

More Intensity

Mindemann almost always double-crops or cover crops after wheat har-vest. His standard double-crop hasbeen soybeans, which commonlymake “18 to 22 [bu/a], about the

same as the full-seasonbeans.” For ’05, Alanplans to try double-cropcotton, if conditions areright, noting that oftenhe has a full profile ofmoisture at wheat har-vest. One of Alan’sfavorite cover crops fol-lowing wheat has beensudan, although hewants to try bin-runmilo for even moreaffordable seed. Alannotes the sudan makesexcellent hay or forage,and will survive rathersevere drought and startgrowing again with fall rains.

Mindemann has also had excellentresults with sunn hemp—his high-est-yielding cotton fields were fol-lowing wheat/sunn hemp, withremarkable uniformity from hilltopto bottom. “We never have had awheat crop uniform in those fields;it would make 10 [bu/a] on the hillsand 50 in the bottom.” He also notesthat the cotton never wilted in thefields that were previously sunnhemp, unlike some other fields.“Those yields shouldn’t have beenpossible. We didn’t have enoughrain. The experts said ‘no way’[could those yields happen with solittle water].” Alan says no-till withheavy residue is part of it, but sus-pects the sunn hemp is doing some-thing in addition.

Alan had uneven luck with cowpeas,however. While he did manage togrow a 600-lb/a seed crop at 28cents/lb (and probably left a majorportion of it in the field when har-vesting with a rigid header), henotes the crop created several issuesfor the cotton the next season,including damaging insects and theneed for LibertyLink cotton to con-trol volunteer cowpeas. For ’05,Alan is also trying a wheat/rye mixand a wheat/turnip mix, which willbe chemically killed several weeksbefore cotton planting. The

wheat/turnip mix has been heavilygrazed, and the turnips are actuallya hybrid called ‘Pasja.’ Alan realizesthe wheat and rye will harbor rootdiseases that will afflict future wheatcrops destined for grain. He doesn’tseem too concerned, perhaps antici-pating another big cotton crop thatwill mitigate any losses in futurewheat crops. But he continues toconsider and recon-

sider his choices, and may try winteroats to solve the problem. Whethergrazed or not, Alan’s winter covercrops of wheat, rye, or turnips getfertilized heavily, which he plans onrecouping in the following cottoncrop. He fully admits to lots ofguesswork as to how to credit that Nto the cash crop, as well as when tokill out the cover crop.

Many of Alan’s cool-season covercrops have been planted with thePhillips harrow, although he plans tocurtail that practice, opting insteadto use the air drill more in thefuture. He explains that the harrow

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Turnips and wheat have been grazed heavily in this field,and are now regrowing. They will be killed several weeksprior to planting cotton, depending on spring weather.

Heavy residue stored extra moisture for his

cotton crop—“Those yields shouldn’t

have been possible.”

Alan’s wheat in cotton stalks. His regionoften has enough moisture and mild win-ter weather that winter wheat can beseeded shortly after cotton harvest.

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plants far too many weeds. In testshe’s done, with checks (no harrow)versus one pass versus two, heobserves those strips later: “I had noweeds, a few weeds, and lots ofweeds [respectively].”

Proving Ground

While Mindemann’s survival andexpansion has always been dictatedon yearly results, he paradoxicallythinks about and manages for thelong-term much more than hisneighbors. He uses solid science andpractical experience to improve eachtract as if he would crop it for cen-turies hence. He builds and main-tains residue levels

carefully. He applies much morefertilizer and lime than neighbors. Ifin the second or third year of no-tillhe detects rooting problems fromold tillage pans, he reluctantly pullsa ripper through those soils—all thewhile lamenting the residue loss, thesurface roughness (smoothed with aPhillips harrow in Alan’s case), andfuture bogging of machinery in thedisrupted soil. Mindemann under-stands the soil aggregation process,and knows the compacted layer isn’tbeing removed by the ripper, butmerely redistributed. He is quitedefinite: “Rip once, and neveragain.”

No-till has been a long hard road forAlan. Although he’s gaining somecredibility in the community, at onetime he “lost leases for ‘not farmingthem right’ ”—in other words, fornot using tillage. Now, he sometimesfinds landlords who come to himwanting their land no-tilled. Hisacumen as a farm manager helpedhim acquire a lease from the City ofLawton, on some land just above the

lake from which the city’s water sup-ply is drawn. Interestingly, the leasespecifies no-till.

Mindemann finds the attitudes oflocal farmers unbelievable at times.He recognizes the economic plightof most, and their despair, “Yet theykeep doing what they’ve always beendoing. . . . It seems like I’m the onlyoptimistic farmer out here.”

Alan’s optimismis rooted in real-ity—the realityof success. Hestarted withnext to nothing,and has madeconsiderableprogress in 9years. He hassome of themost modernmachinery inthe neighbor-hood, very littledebt, and hisbanker tells himhis cash flow isgood on hiscropping enter-prise. And whilesome of his oddjobs helped himget started, hisown croplandoften generatesthe majority ofhis profits now.

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Mindemann is in ‘high cotton,’ literally and figuratively. The crop is one of many to shinewith Alan’s skillful management.

Using a rolling harrow: “I had lots of weeds.”

His banker even asked him to speakto a group of farmers at aProduction Credit Association meet-ing— “He said to me, ‘Of all thefarmers out here doing differentthings, I see the end result—nobullshit, no fudging. I want you totalk to them.’ ”

Expect Mindemann to keep doingwhat everybody says can’t be done.

Crop residues are what make no-till go. Without ade-quate surface residues, the soil is susceptible to damageby raindrops, leading to surface sealing, erosion, andlater a brick-like surface.

Because water infiltration is closely tied to surface cover(see graph), and because crop yields are largely deter-mined by water availability, it should be obvious thatmaintaining surface residues is of utmost importance.Yet these residues are frequently called “trash” andregarded as if of little or no value. Even those who haveembraced no-till as a permanent system are frequentlyguilty of not treating their residues with the necessarycare.

Residue decomposes by both biological and chemicalactivity. The process happens more quickly when tem-peratures are warm (68 to 95° F reportedly ‘optimum’1),and when moisture is available. Warmer, wetter regionshave more difficulty maintaining surface residues andsoil OM—for instance, it’s a lot tougher to build surfaceresidues in Oklahoma than in Manitoba, and more diffi-cult in Brazil than in Argentina. Those warmer and morehumid regions especially need to focus on growing morebiomass and preserving it as long as possible.

Residue standing decomposes more slowly than thatwhich is lying on the soil surface—this is no differentthan wood fenceposts rotting at or just below the soilsurface, but the portion sticking up in the air lasts muchlonger. Residue buried at a shallow depth (1 – 2 inches)also decomposes very quickly.

The no-tiller has begun the process of understanding thatsurface residues equate to moisture available to thecrop during its growth cycle. Yet manyno-till field opera-tions result inmore stubbledestruction thanthey should. Forinstance, many no-tillers think it nec-essary or desirableto apply fertilizersubsurface withsome type of applicator as a separate pass. Some buy orequip their planters or drills with additional openers toapply fertilizer. Some people use their air drills to placefertilizer during a separate pass. Other no-till producerslose too much residue during their seeding pass, or sim-ply don’t grow enough in the first place. Let’s examinesome of these issues in more detail.

Fertilization

A separate pass with soil-engaging openers to apply fertil-izer could result in destroying (burying, slicing and/orflattening) 10 to 50% of the residue either immediately orin a few weeks of accelerated decomposition. On the U.S.Plains or other regions where moisture is frequently alimiting factor, this residue loss has a high likelihood oftranslating into yield loss in the next crop. For instance, ifabundant wheat stubble lets you store an additional 4inches of water for growth of the next crop (+4 inches oftranspiration),2 and the other agronomy is proper (no

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Maximize Crop Residuesby Matt Hagny

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A thatch of residue lets the soil store more water, which is almostalways a limiting factor in agriculture.

Surface residues equate tomoisture available to the

crop. Yet many no-till fieldoperations result in morestubble destruction than

they should.

1 D. Tanaka & V. Hoffman, 1994, Residue Reduction, in Crop Residue Management To Reduce Erosion and Improve Soil Quality (Northern Great Plains), ed.W.C. Moldenhauer & A.L. Black, USDA-ARS.

2 An 80 bu/a winter wheat crop may produce 7,000 lbs/a of straw. One study reports a value of 0.4 inch of additional water stored for every 900 lbs/a ofwheat straw. So 7,000 lbs of straw would store an additional 3.1 inches of moisture. (B.W. Greb, 1983, Water conservation: Central Great Plains, inDryland Agriculture, ed. H.E. Dregne & W. O. Willis, American Society of Agronomy.) Various studies from Texas to the Dakotas produce roughly similarnumbers. Long-term no-till tends to be even more efficient due to improved structure with the result that precipitation moves away from the surfacemore quickly. (See also R. Ward, 2003, Drought Conditions Spur Additional Discussion, WardLetter [Feb. 2003], Ward Laboratories Inc. [Kearney, NE]. D.C.Nielsen, ca. 2002, Crop Rotation, Soil Water Content & Wheat Yields, Conservation Tillage Fact Sheet #1-02, USDA-ARS Central Great Plains ResearchStation, Akron, CO. P.W. Unger, E.G. Krenzer, Jr. & C.A. Norwood, 1994, Soil-Water Conservation, in Crop Residue Management To Reduce Erosion andImprove Soil Quality [Southern Great Plains], ed. B.A. Stewart & W.C. Moldenhauer, USDA-ARS.)

Matt Hagny is a consultingagronomist for no-till sys-tems, based in Wichita, KS.T E C H N I Q U E

responses to the treatments with the most residue andthe least soil disturbance.

Many legitimate reasons exist for wanting to use a sepa-rate fertilizer pass. Some producers strive to improvetheir planting-time efficiency by applying fertilizer in theoff-season. Or, the desired timing of nutrient availabilityor the desired fertilizer source does not lend itself easilyto application during seeding. But does all this fertilizerneed to be put into the soil?

The arguments are often that placing fertilizer with astrip-till rig (or other subsurface applicator) is a muchmore efficient method of delivering nutrients. Thatdepends. Nitrogen, as well as sulfur and potassium, aresufficiently mobile that they can be applied on the sur-face. On dryland, this may involve b’casting urea or

yield limitations from nutritional shortages, etc.), thiscould easily translate into a +45 bushel response in cornor milo the following year, or +20 bu/a in wheat.3 Theresponse numbers will vary greatly by region, not tomention rotations and other production practices, butthat is not the point. What we are focusing on here is thefact that, in areas where moisture is limiting, crops yieldmore when previous residues are left intact. And if 10 to50% of those residues are lost via the ‘extra’ field opera-tions in question, then 10 to 50% of the yield boost islost as well.

Let’s say you’re doing a nice job with a low-disturbanceapplication tool set on relatively wide spacing, so you’reonly losing 10% of your residue. This means you couldbe leaving 4 bu/a of corn or milo ‘on the table,’ or $8 to$10/a. This is in addition to the actual direct cost of mak-ing that extra trip across the field—the man-hours, trac-tor hours, and cost of owning or rentingthe applicator. Wehaven’t even both-ered to figure theweed seed burial,although at leastseveral peoplehave commentedthat weed controlis noticeably morecostly when someadditional distur-bance is in the system, such as with strip-till.

So does this residue destruction show up in the fertilizerresearch? No, at least not very conclusively. But otherfactors often mask this loss. The trial site may be low-yielding due to poor rotations. Seeding equipment maybe inadequate for no-till, and so only when some distur-bance is added back do the stands get anywhere close tooptimum. Sometimes fertilizer loss (e.g., N volatilization)or improper methods result in no response (imagineb’cast P vs. subsurface application on a low-testingfield—with none at seeding). If N, P, K, S, Zn, or anyother nutrient is more limiting than moisture, then, asexpected, the treatments with the least disturbance don’tproduce the highest yields. Many, if not most, of thestudies are biased against pure no-till and maximumresidues from the outset (quite often inadvertently, sincemost researchers have a decent idea of how to growcrops with tillage, but good no-till practices take a bitmore thought and effort). However, if the agronomy ishalfway decent for no-till, and moisture is somewhat lim-iting during the season, we typically see significant

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Field operations for planting and fertilizing should be managed soas to keep as much residue intact as possible.

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3 G.A. Wicks, D.A. Crutchfield & O.C. Burnside, 1994, Influence of wheat (Triticum aestivum) straw mulch and metolachlor on corn (Zea mays) growth andyield, Weed Sci. 42: 141-147. See also D.C. Nielsen, R.L. Anderson, R.A. Bowman, R.M. Aiken, M.F. Vigil & J.G. Benjamin, 1999, Winter Wheat & ProsoMillet Yield Reduction Due to Sunflower in Rotation, J. Prod. Agric. 12: 193-197. D. Beck, 1990, Rotational Systems: The Key to Successful No-Till, inProceedings: Manitoba-North Dakota Zero-Till Conference (available at http://www.no--till.com/publications/mandk290.pdf). R. Ward, 2003.

Ideally, at least some P isin close proximity to the

seed for early growtheffects, and the only wayto do that properly is with

the seeder.

Total runoff in no-till after 60 minutes of simulated rainfall asaffected by % soil cover. (Adapted from R. Derpsch citing C.H.Roth, 1985.)

streaming UAN during the late winter or early spring. Inextremely dry regions, this surface application will needto be done during times of the year when precip eventsare more likely, and with sufficient time ahead of cropdemand so that the nutrients are moved intothe root zone. In more humid regionswhere denitrifica-tion and leachingare problematic,the timing will bemoved closer toplanting or evenpost-emerge. (Forfurther explana-tion, see RayWard’s article on Nmanagement inthe Sept. ’04Leading Edge.) Under pivot irrigation, the N can easilybe surface applied either before or after planting, andirrigated into the soil in a very controlled and efficientmanner.

The remaining P fertilizer that needs to go out can beapplied at planting. Ideally, at least some P is in closeproximity to the seed for early growth effects, and theonly way to do that properly is with the seeder. (Strip-tilldoesn’t accomplish this without messing up the zone intowhich you want to plant: after the strip-till shank is done,this zone may be too dry, too rough, or have too many airpockets and voids to effectuate a good seedbed.) Somewill argue that they don’t want the mess of liquid fertil-izer on their planters, or the extra fill time. These objec-tions are more perception than reality—placing fertilizer

through a Keeton in-furrow is relatively ‘clean,’ and youcan just as well be pumping on liquid fertilizer while youfill your seed boxes or tank. Better yet, hook an air cartonto your planter and deliver dry fertilizer blends to theseed furrow and/or a separate fertilizer opener; this sys-tem is even cleaner, and lower cost per unit of P applied(compare the cost per unit of P for dry versus liquid).

Seeding

Another aspect of the loss of residue is how much getsflattened or buried during the seeding operation itself.Hoe or knife openers bury 50 to 60% of residue, andaggressive coulters on narrow spacing can be even worse.Disc openers that lack gauge wheels alongside them (orwiper wheels or other devices to keep soil from followingthe blade up and out of the furrow) can bury a substantialamount of residue, often up to 40%. The best low-distur-bance openers on the market today will result in ~ 15%residue loss typically, and often will flatten4 considerably

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4 Flattening isn’t nearly so serious as pulverizing or burying the residue. Flattening of residue does result in faster decomposition, as noted previously. Onthe plus side, it also suppresses weeds more effectively and improves infiltration most when flat on the surface—hence, the opposing viewpoint of knock-ing residue down with harrows or heavy rollers (such as are used in Brazil and Paraguay on cover crops) to get these advantages immediately. However,the rolling of cover crops only works well with a few species (e.g., sunn hemp, black oats, rye), and only if the next crop is seeded immediately. Maturestubble not seeded to cover crops is generally not rolled down. On the U.S. Plains, where the wind blows, and the next crop of residue is uncertain, thebest plan appears to be keeping as much standing for as long as possible.

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Losing too much residue in the row can cause washing, as seenhere. Crusting may also result.

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With the right set of tools and some attention given to their use,growing excellent crops in heavy residue is no problem!

After the strip-till shank isdone, the intended plant-ing zone may be too dry,too rough, or have toomany air pockets and

voids to effectuate a goodseedbed.

more (however, the 3-inch gauge wheels and wiper wheelstrample much less than the 4.5-inch versions). All toooften the price of the drill is the primary factor in thedecision, without regard for amount ofresidue destroyedor for accuracy ofseed placement.

Row spacing isanother considera-tion. Generally,narrow rows (inany crop) aredesirable for reducing evaporation and for shading outthe weeds, as well as yield potential. However, it makesno sense to run more openers than necessary. Forinstance, when seeding milo with a grain drill, half theopeners should be locked up to arrive at a 15- or 20-inchspacing.5 Seeds should be crowded in the row to someextent—they certainly shouldn’t be farther apart in therow (on avg.) than between the rows. Similarly, half theopeners should be locked up when seeding soybeanswith a drill, since 15 inches is a desirable spacing for soy-bean rows across much of the U.S.

Controlling seed costs and achieving good stands arecritical to success. Just try not to destroy any more stub-ble or lift any more soil than absolutely necessary to getthe job done.

Growing It

The other side of the coin is how much residue yougrow. Input choices, methods, and rotationsmake a huge impact on how muchresidue gets pro-duced in the firstplace. As a generalrule, practices thatproduce moregrain typicallycause more stub-ble to be grown aswell, so one couldassume that we’ve got this one in our cross hairs. Thatdoesn’t always seem to be the case, however, and part ofit is simply the newness of no-till and lack of research.

Since wheat is a major cash crop on the U.S. Plains, aswell as a critical source of surface residue, getting thepractices ‘right’ for this crop is of utmost importance.For instance, my observations have been that the aver-age no-tiller (we’re all better than average, right?) paysfar too little attention to basic agronomy for wheat, suchas planting an adequate density of high-quality seed,

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Seeds certainly shouldn’tbe farther apart in the row

(on avg.) than betweenthe rows.

Hoe or knife openers bury50 to 60% of residue, andaggressive coulters on nar-row spacing can be even

worse.

5 In very dry, long-season regions, such as w. Texas, the optimal row spacing for milo may be wider than 20 inches.

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When seeding soybeans with a grain drill, locking up half theopeners preserves a bit more residue. Canopy and yield are typi-cally unaffected.

maintaining proper depth and furrow closure, usingoptimum rates of pop-up fertilizer, and following upwith the necessary weed control and a good N fertiliza-tion scheme. Producers in the same area may have yielddifferences of 30 – 40 bu/a persisting over many years—due entirely to production practices.

If you are having trouble establishing winter wheat fol-lowing a late-maturing summer crop, change the rota-tion. If you are having trouble establishing it in chem-fallow, again, change the rotation (see Beck’s article inthe last Leading Edge). If your drill will not consistentlygive you wheat stands that emerge well and survive thewinter, do something about it. It makes no economicsense to run a $100,000 tractor pulling a $30,000 drillincapable of doing the job correctly.

Corn, milo, wheat, oats, barley, millet and other grasscrops are all important sources of residue. Choosing tallvarieties or hybrids, achieving proper stands, fertilizingappropriately, and keeping some of the more criticalpests at bay will help ensure that residue production isas good as it can be for that year’s conditions. Likewise,

keeping broadleaf and other low-residue crops to a mini-mum in the rotation will help—generally, 20 to 25%broadleaf crops is plenty.

Some will argue that their crops planted into heavyresidue don’t emerge well and tend to lan-guish early in the season while cropsplanted intolighter residue arejumpin’. Thisshould be no sur-prise, since tem-perature drivesmany of these processes. But the tale is yet to be fin-ished—all too often, by mid- to late-season, moisture hasbecome a limiting factor. Early growth is not the soledeterminant of yield.

Still, we do not want to sacrifice any opportunities toimprove early growth and preserve even more yieldpotential. Toward that goal, methods such as pop-up fer-tilizer (in proper quantities), row-cleaners, high-vigorseed, seed treatments, etc. can be of economic benefit.

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The No-Till on the Plains 2005 Winter Conferencebrought many new thoughts to the fore. Dwayne Beckpresented a talk titled ‘Do You C What I C?’—focusingon the logical sequence from carbon being the singlemost important plant nutrient, to CO2 levels in-canopyaffecting plant efficiencies, to our ability to influence thetiming of CO2 fluxes from decomposing residue on thesurface. While much research needs to be done in thearea, it is an intriguing possibility and an importantchange of mindset—C as something to be managed forthe crop’s benefit.

César Belloso brought forth the Argentinean practice offertilizing soybeans with sulfur—applied in the crop pre-ceding the soybeans. Belloso also presented long-termwhole-farm experiences with rotations relying to various

degrees on soybeans,showing the negativeimpact of overuse ofthis crop.

Dirceu Gassen made usthink when notingfarmers’ explanations ofwhy they do tillage—“ ‘loosening the soil,improved water absorp-tion, better rootgrowth,’ ”—differed

markedly from the reasons roadbuilders give for doing tillage—“ ‘tobreak the soil structure, compactthe soil, make the soil not perme-able’—One of them is wrong!”

Gassen also described terraces as“Monuments to ignorance”—theresult of faulty thinking from theoutset. Gassen admonished, agriculturalists should haveknown the water and soil could not be held in placewithout eliminating tillage and keeping residue cover onthe soil.

These and dozens of other speakers presented valuableinsights on a wide array of topics. Their talks are cap-tured on recordings, and available on CD or cassettefrom No-Till on the Plains, Inc., at 888-330-5142, orshop online at www.notill.org.

Conferring Knowledge

Jill Clapperton

Steve Groff

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Informative speakers helped us gain new levels of understanding.

Well-maintained opener blades, seed tubes, etc. willhelp, as will running adequate down-pressure on theopeners to slice through the surface residues and keepthem out of the furrow while the seed is placed. In someclimates and rotations, the soil might already have a ten-dency to become saturated by the planting of the nextcrop—in this case, additional residues will be problem-atic unless more water is extracted with intensified crop-ping or cover crops.

For nearly all agricultural regions and crops, shortage ofmoisture is a limiting factor at various times during thegrowing season. Increased surface residues dramaticallyimprove moisture efficiency, whether from rainfall orirrigation (the only difference is whether you have anycontrol over the amount and timing). Growing and main-taining high residue levels are therefore merely a meansto a profitable end.

‘Residue’ denotes something that is left over—which itis, following a harvest. In the case of cropping systems,what remains is quite valuable for what it retains.

Early growth is not thesole determinant of yield.

Crop Residues & No-till Stimulate a Spiral of

Soil Regenerationby Randy Anderson

Randy Anderson is a USDA-ARS scientist at Brookings, SD,formerly at Akron, CO.S C I E N C E

(The following is adapted from anarticle published in Journal ofSustainable Agriculture, 2005, withsome information updated here withapproval of the author.)

Soils in the central Great Plains ofthe U.S. were severely damaged bywind erosion during the Dust Bowlera and from the effects of decadesof tillage. The damage is partiallyreversible with more intensive crop-ping, residue cover, and no-till.

Ten years into a rotational study atAkron, CO, we examined ecologicaltrends associated with soil structure,nutrient cycling, and pest manage-ment as affected by rotations. Weexamined crop yield in relation tocrop sequencing and interval. Also,we suggest crop rotations that mayfurther enhance regeneration andsustainability of soil.

Introduction

Winter wheat >>summerfallow hasbeen the main rotation in the cen-tral Great Plains since the 1930s.Producers developed this rotation inresponse to the region’s semiarid cli-mate where yearly precipitationranges from 350 to 500 mm (13.8 to19.7 inches) per year. During fallow,neither crops nor weeds are allowedto grow; therefore, precipitationduring fallow is stored in the soil.Soil water gained during fallowreduces yield variability and croploss due to drought stress. (Editors:The tilled summerfallow techniquewas developed prior to the wide-spread availability of commercialfertilizers, and its initial success mayowe more to the supplying of nutri-ents from breakdown of soil OMthan to the storage of water.)

A consequence of winter wheat>>fallow is loss of soilorganic matter due toaccelerated decompo-sition and removal bywind (and water) ero-sion. Of the originalorganic matter presentin soil, as much as60% has been lost.1 Asecond characteristicof winter wheat >>fal-low is its inefficiencyin using precipitationfor crop growth.

Generally, less than half of precipita-tion received during the 2 years isused by winter wheat.2 The rest islost to evaporation, runoff, or leach-ing below the rooting zone of winterwheat.

During the 1980s, producers startedreplacing tillage with herbicides tocontrol weeds during

fallow. Eliminating tillage during fal-low increases precipitation storage20% and winter wheat yield 14%.3

Because no-till stores more precipi-tation in soil, producers began grow-ing corn, sunflower, sorghum, orproso millet in sequence with winterwheat and fallow.4 To help produc-ers plan new rotations, scientists inthe region initiated several croppingsystems studies, including a study atAkron, Colorado. With the Akronstudy, land productivity (total grainproduced divided by number ofyears in the rotation) was increasedtwo-fold by rotations comprised of adiversity of crops compared with

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Organic matter (OM) in soil occupies a pivotal

role in semiarid crop production because of its large influence on

resource availability andyield stability.

Research shows how critical stubble retention is to maintain-ing soil productivity.

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1 R.A. Bowman, J.D. Reeder & L.W. Lober, 1990, Changes in soil properties after 3, 20, and 60 years of cultivation, Soil Sci. 150: 851-857.2 R.L. Anderson, 1998, Designing rotations for a semiarid region, in Proceedings: 10th Annual Meeting, Colorado Conservation Tillage Association (Sterling

CO, 4-5 February 1998), Colo. Conserv. Tillage Assoc. H.J. Farahani, G.A. Peterson & D.G. Westfall, 1998, Dryland cropping intensification: a fundamentalsolution to efficient use of precipitation, Advances in Agronomy 64: 197-223.

3 D.E. Smika, 1990, Fallow management practices for wheat production in the Central Great Plains, Agron. J. 82: 319-323. (Editors: The most recent datafrom Akron indicate wheat yield increases of 20%. M.F. Vigil, 2005, PowerPoint presentation at the No-Till on the Plains Winter Conf. [Salina KS, 24-25Jan. 2005].)

4 G.A. Peterson, A.J. Schlegel, D.L. Tanaka & O.R. Jones, 1996, Precipitation use efficiency as affected by cropping and tillage systems, J. Prod. Agric. 9:180-186.

winter wheat >>fallow. For example,winter wheat >>fallow (tilled)yielded 890 kg/ha, contrasting with arotation of winter wheat >>corn>>proso millet >>fallow where landproductivity was 2030 kg/ha, anincrease of 128%. An intriguingtrend was that a rotation with con-tinuous cropping (no long fallow),winter wheat >>corn >>proso mil-let, also yielded two-fold more thanwinter wheat >>fallow.

Rotations comprised of a diversity ofcrops also increase economicreturns. Winter wheat >>corn>>proso millet >>fallow provides25% more net return than winterwheat >>fallow.5 Another studyreported that diverse rotations weremore profitable than winter wheat>>fallow throughout western Kansasand eastern Colorado.6 This studyalso found crop diversity reducedfinancial risks compared with wheat>>fallow. Other studies from semi-arid regions have

shown crop diversity in conjunctionwith residue retention and no-tillprovide viable alternatives to fallowin managing yield variation andfinancial risk.7

Astute producers are seeking rota-tions that not only are economical,but also improve soil quality thusenhancing sustainability of their pro-

duction systems. One goal of sus-tainability is to integrate knowledgeof ecological processes into manage-ment decisions.8 Sustainable systemswould sequence crops to enhancefavorable ecological processes.

Akron Site Details

Design and management of thecropping systems study at Akron,Colorado has been described indetail elsewhere.9 Therefore, weonly present general informationrelated to agronomic practices. Thesoil is a Weld silt loam with anorganic matter level of 1.5%. Annualprecipitation for the location aver-ages 418 mm (16.4 inches); during1990 to 1999, yearly precipitationranged from 310 to 530 mm, andaveraged 422 mm. Elevation is 4600ft. Rotations were comprised of vari-ous combinations of winter wheat

(abbreviated as W), corn (C), prosomillet (Mlt), sunflower (Sf), or fal-low (F), with all phases of a rotationpresent each year, with 3 replica-tions of each phase.

With W-F, three tillage systemswere compared, conventional,reduced, and no-till. The conven-tional-tillage system (CT) consistedof several tillage operations in eachfallow period with a sweep plow,whereas the reduced-till (RT)included only one operation per fal-low. With other rotations thatincluded fallow, tillage occurredonce or twice during fallow from ’90to ’95, but this tillage was eliminatedthereafter.10 From ’95 to ’98 thesunflowers were v-bladed pre-plantto incorporate Sonalan or Treflan;from ’99 on, Spartan was used andno v-blading done. After ’99, tillagewas completely eliminated from allplots, except the W-F (CT).

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Of the original organicmatter present in soil, as

much as 60% has been lost.

Wheat is important to Plains rotations. Wheat yields were greatly decreased in some rota-tions at Akron, CO. The study has been in place for 14 years, with some important effectsonly becoming apparent after 8 – 10 years. To a large degree, crop sequencing andresidue levels determine whether rotations succeed or fail at Akron.

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5 G.A. Peterson, D.G. Westfall, N.E. Toman & R.L. Anderson, 1993, Sustainable dryland cropping systems: Economic analysis, Bulletin TB93-3, ColoradoState University Agric. Exp. Station.

6 K.C. Dhuyvetter, C.R. Thompson, C.A. Norwood & A.D. Halvorson, 1996, Economics of dryland cropping systems in the Great Plains: a review, J. Prod.Agric. 9: 212-216.

7 R.P. Zentner, D.D. Wall, C.N. Nagy, E.G. Smith, D.L. Young, P.R. Miller, C.A. Campbell, B.G. McConkey, S.A. Brandt, G.P. Lafond, A.M. Johnson & D.A.Derksen, 2002, Economics of crop diversification and soil tillage opportunities in the Canadian prairies, Agron. J. 94: 216-230.

8 B.R. Stinner & G.J. House, 1989, The search for sustainable agroecosystems, J. Soil & Water Conserv. 44: 111-116.9 R.L. Anderson, R.A. Bowman, D.C. Nielsen, M.F. Vigil, R.M. Aiken & J.G. Benjamin, 1999, Alternative crop rotations for the central Great Plains, J. Prod.

Agric. 12: 95-99. R.A. Bowman, D.C. Nielsen, M.F. Vigil & R.M. Aiken, 2000, Effects of sunflower on soil quality indicators and subsequent wheat yield,Soil Sci. 165: 516-522. R.A. Bowman, M.F. Vigil, D.C. Nielsen & R.L. Anderson, 1999, Soil organic matter changes in intensively cropped dryland systems,Soil Sci. Soc. Am. J. 63: 186-191.

10 However, in ’97, an unsupervised technician v-bladed all the fallow treatments, including the W-F (NT) plots. Over 15 technicians are involved, and theongoing study is now on its third team leader.

Continuous-cropping rotations wereno-till (NT) in all years.

Nutrient management for each rota-tion was based on soil tests obtainedeach year and projected crop yield.Nitrogen was applied broadcast,whereas phosphorus (P) was appliedonly to winter wheat, being bandedwith the seed at planting. Weedswere controlled within and betweencrops with herbicides and manage-ment practices commonly used byproducers in the region.

Spiral of Regeneration

Precipitation storage during fallowincreases with higher levels of cropresidues on the soil surface.11

Consequently, winter wheat not onlyyields more but also produces morecrop residue, which furtherimproves precipitation storage andfuture crop growth. We visualizeresidue retention as initiating a spi-ral of change, where greater poten-tial crop growth enables producers

to add other crops to the W-F rota-tion, thus diversifying the produc-tion system. With crop diversity,rotations can enhance various eco-logical processes related to soilstructure, nutrient cycling, and pestmanagement.

We view this change as a spiral ofregeneration, where residue reten-tion (especially in

continuous no-till) serves as thefoundation for sustainable croppingsystems that improve or regeneratesoil. With this paper, we describethe effect of cropping systems onecological processes favored byresidue retention, no-till, and cropdiversity.

Soil Structure Changes

Organic matter (OM) in soil occu-pies a pivotal role in semiarid cropproduction because of its large influ-ence on resource availability andyield stability.12 OM improves pre-cipitation infiltration into soil as wellas water-holding capacity.13 After 8years in the Akron study, OMincreased approximately 20% in thetop 5 cm (2 inches) of soil with con-tinuous cropping systems comparedwith wheat >>fallow (avg. of CT, RT& NT).14 A similar trend occurredwith soil organic N level. However,OM and N levels did not increase if

fallow was included in a rotation,even if three crops were grownbefore fallow. The authors con-cluded that fallow had a negativeinfluence on organic carbon and Naccumulation, whereas continuouscropping favored accumulation ofthese nutrients. (Editors: The factthat the continuous cropping had notillage in any year of the rotationprobably contributed. However,quantity of residue returned to thesoil plays a major role, as demon-strated by various other studies.)

The level of glomalin in soil also wasmeasured in several rotations.15

Glomalin, a glycoprotein producedby mycorrhizal fungi, contributes toaggregate stability. Both glomalinlevels and aggregrate stability werehigher in W-C-Mlt than with W-F.As found with OM, fallow was adetriment to glomalin accumulation,as glomalin levels in any rotationwith fallow did not differ from W-F.

Surprisingly, some rotations with adiversity of crops, such as W-Sf-F,were more detrimental to soil struc-ture than W-F. We initially notedthis trend with winter wheat yields;compared to W-C-Mlt-F, win-ter wheat yielded

36% less in W-Sf-F, even though fal-low preceded winter wheat in bothrotations. When sunflower wasgrown in a four-year rotation, W-C-Sf-F, winter wheat yield was notreduced compared with W-C-Mlt-Fduring the ’94–’99 period of thestudy,16 but in subsequent years

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Proso millet is a viable crop for many pro-ducers in eastern Colorado, but milletdoes not make an easy transition to wheatyet that fall in dry regions such as Akron.

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Residue retention (in con-tinuous no-till) serves as

the foundation for sustain-able cropping systems thatimprove soil. We view this

change as a spiral ofregeneration.

With some rotations, win-ter wheat yields decreased

over the years.

11 Peterson et al., 1996.12 P.E. Rasmussen & H.P. Collins, 1991, Long-term impacts of tillage, fertilizer, and crop residue on soil organic matter in temperate semi-arid regions,

Advances in Agronomy 45: 93-134.13 Rasmussen & Collins, 1991.14 Bowman et al., 1999. For 0 – 15 cm, the change in OM was not statistically significant. 15 S.F. Wright & R.L. Anderson, 2000, Aggregate stability and glomalin in alternative crop rotations for the central Great Plains, Biol. Fertil. Soils 31: 249-253.16 Anderson et al., 1999.

(’00–’01) wheat yields were reducedas much or more than in W-Sf-F.17

We also noticed a second trend withW-Sf-F; winter wheat yielddecreased over time compared toW-C-Mlt-F (see theSept. ’03

Leading Edge for graphs).18 WithW-Sf-F, winter wheat yield declinedfrom 81% of W-C-Mlt-F in 1994 to48% in 1999, a loss of 7% per year(r2 = 0.86). This trend eventuallyoccurred with W-C-Sf-F also.19

We were perplexed as to why winterwheat yields in W-Sf-F were so lowas well as declining over time.Speculating that this effect may berelated to crop residue factors, agroup of scientists examined soilsurface characteristics of W-Sf-Fand W-C-Sf-F in the eighth year ofthe study.20 They found that bothsoil surface cover and biomass ofcrop residue at winter wheat plant-ing were 50% less with W-Sf-F com-pared with W-C-Sf-F. Also, soilorganic C was 10% less in W-Sf-F.They suggested that corn, because ofits high residue production, compen-sated for low residue production bysunflower in W-C-Sf-F.

Also, we found that soil aggregateswere less stable in W-Sf-F comparedwith W-C-Mlt-F.21 A surprising find-ing with this study was that aggregate

stability in W-Sf-F was even less thanwith W-F. Apparently, W-Sf-F is verydamaging to soil aggregation, evencompared to W-F (CT). One causemay be the low biomass of sunflowerresidue. Thus, the surface 2 inches ofsoil essentially does not have anyplant residue being added for 2 years(sunflower year and fallow), drainingthis layer of OM. Improvement ofaggregate stability is a slow process,comparing W-C-Mlt to W-F (CT),but damage occurs rapidly as demon-strated by W-Sf-F. Both researchteams suggested that W-Sf-F wasdetrimental to soil structure.

Field observations support thishypothesis, as water ponds on thesoil surface after rain with the W-Sf-F rotation but not with W-C-Sf-F orW-C-Mlt-F. Soil in W-Sf-F appar-ently crusts more easily, thus limit-ing water infiltration and futurewater use bywinter wheat.

With theAkron study,continuouscroppingimproved soilstructure andOM levels. Incontrast, fal-low minimizedsome of thebenefits ofmore intensivecropping, evenif fallow fre-quency wasreduced toonce everyfour years.The negativeimpact of sun-flower on soilstructure and

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The negative impact ofsunflower on soil structureand subsequent crop yieldshows how critical residuecover and crop sequence

are to cropping systems inthis semiarid region.

17 Vigil, 2005.18 Anderson et al., 1999.19 Vigil, 2005.20 Bowman et al., 2000.21 Wright & Anderson, 2000.22 Anderson, 1998. Farahani et al., 1998.23 Anderson, 1998. (Editors: How far the precipitation conversion can be pushed depends on many details of the system—crop sequence, residue preserva-

tion, fertilization, stand establishment, etc.—as well as soil depth, texture, and OM.)

Ag

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W-F(CT)

W-C-Mlt(NT)

W-C-F(RT)

W-Sf-F(RT)

0

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6

9

12

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Improvement in aggregate stability was about 10% in W-C-Mlt(NT) compared to W-F (CT) after 8 years. Stability did not changebetween W-F (CT) and W-C-F (RT). However, aggregate stabilitydecreased with W-Sf-F (RT), 7.4 compared to 11.6 for W-F (CT).(Adapted from Wright & Anderson 2000.)

subsequent crop yield shows howcritical residue cover and cropsequence are to cropping systems inthis semiarid region.

Precipitation Into Grain

As noted earlier, winter wheat>>fallow converts 40 to 45% of pre-cipitation into grain; the rest of pre-cipitation is lost as described.Rotations such as W-C-Sf-F or W-C-Mlt-F convert approximately 60%of precipitation into grain, whereaswith continuous cropping, precipita-tion use approaches 75%.22

However, with continuous cropping,our agroecosystem likely does notsupply enough water to grow allcrops for grain. For example, withW-C-Mlt or W-W-C-Mlt, averageyields would require 85% of precip-itation to be converted into cropgrowth.23 In contrast, average yields

with W-C-Mlt-green fallow wouldneed only 70% of precipitation forcrop use.

One benefit with crop diversity isthat some crops improve water-useefficiency (WUE, grain producedper unit of available water) of fol-lowing crops. For instance, dry pea(field pea, Pisum sativum) mayimprove winter wheat WUE.Preliminary research at Akron indi-cates that WUE of winter wheat was15 to 25% greater after dry pea(grown as forage) compared witheither winter wheat or proso millet

as previous crops. Some cropsequences mitigate the impact ofdrought on yield variability;researchers found that diverse rota-tions improved drought toleranceand WUE of corn.24

Continuous cropping and no-tillfavor survival of mycorrhizae insoil,25 which improves drought toler-ance of winter wheat.26 Thus, cropdiversity and proper sequencingcould improve crop growth suchthat fallow is not needed.

Nutrient Cycling

Fallow also affected nutrient-useefficiency in the Akron study.Scientists found that concentrationof P in winter wheat was 13 to 30%greater in rotations with continuouscropping compared with rotationsthat included fallow, suggesting thatP-use efficiency was reduced by fal-low.27 They attributed this trend torecycling of P through plant residue,as P is more available for plantuptake in the organic phase, eitherin plant biomass or with organicmatter. During fallow, chemicalreactions in soil convert P into inor-ganic forms that are less accessibleby plants, whereas yearly contribu-tions of plant biomass in continuouscropping favor the organic phase ofP. (Editors: This could be partly amycorrhizal effect.)

In the central Great Plains, W-Fleads to N leaching in the soil pro-file.28 At Akron, N level in soil wasmeasured to a depth of 1.8 m (6 ft)in 1996. As expected, N quantity in

the lower soil profile was highestwith W-F compared with other rota-tions. However, N leaching occurredwith all rotations that included fal-low, even rotations comprised ofthree crops and a fallow. In contrast,N did not leach with continuouscropping. Another research teamreported similar results in the semi-arid prairies of Canada; continuouscropping reduced N leaching in soilcompared to rotations with fallow.29

Deep leaching of

N during fallow occurred mainlyduring years with above-normal pre-cipitation. In Canada, scientistsattributed the reduced N leaching incontinuous cropping to greater syn-chrony between N release by miner-alization and N uptake by the crop.30

In addition to improved nutrientuptake, crops can utilize those nutri-ents more efficiently to producegrain with some sequences than oth-ers. For example, investigating thebeneficial effect of dry pea on springwheat yield, researchers concludedthat only 8% of the yield effectcould be attributed to N availabil-ity.31 These scientists cited other

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Planting wheat into prosostubble results in a verylow soil moisture condi-

tion for wheat. During dryyears, wheat growth is

always severely reduced.Low wheat residue alsoleads to low corn yields.

24 W.W. Sahs & G. Lesoing, 1985, Crop rotations and manure versus agricultural chemicals in dryland grain production, J. Soil & Water Conserv. 40: 511-516.

25 N.C. Johnson & F.L. Pfleger, 1992, Vesicular-arbuscular mycorrhizae and cultural stresses, in Mycorrhizae in Sustainable Agriculture, Special Publication No.54, ed. G.J. Behlenfalvay & R.G. Linderman, American Society of Agronomy.

26 J.R. Ellis, H.J. Larsen & M.G. Boosalis, 1985, Drought resistance of wheat plants inoculated with vesicular-arbuscular mycorrhizae, Plant and Soil 86: 369-378.

27 R.A. Bowman & A.D. Halvorson, 1997, Crop rotation and tillage effects on phosphorus distribution in the Central Great Plains, Soil Sci. Soc. Am. J. 61:1418-1422.

28 D.G. Westfall, J.L. Havlin, G.W. Hergert & W.R. Raun, 1996, Nitrogen management in dryland cropping systems, J. Prod. Agric. 9: 192-199.29 R.P. Zentner, C.A. Campbell, V.O. Bieberbeck, P.R. Miller, F. Selles & M.R. Fernandez, 2001, In search of a sustainable cropping system for the semiarid

Canadian Prairies, J. Sustain. Agric. 18: 117-136.30 Zentner et al., 2001.31 F.C. Stevenson & C. van Kessel, 1996, The nitrogen and non-nitrogen rotation benefits of pea to succeeding crops, Can. J. of Plant Sci. 76: 735-745. (The

yield response was +43%.)

Practices that increase the probability ofgood wheat yields also will increaseresidue levels from that crop, which inturn increases the probability of a goodcorn crop. The studies at Akron show thespiral works both ways.

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Cropping sys-tems are rap-idly changingin the centralGreat Plains,providing anopportunityfor producersto designcropping sys-tems thatintegrate cropsequencingwith ecologicalprinciples. Wesuggest thatarrangingcrops intorotations withlong intervals,such as W-C-Mlt-F, willaccrue themost ecologi-cal benefits,especially withpest manage-ment. Yet, itwould be desir-able to eliminate fallow for soil qual-ity reasons, as well as productivity.Soil quality

improved more rapidly with W-C-Mlt than with W-C-Mlt-F becauseof continuous cropping.

Despite advantages for soil quality,W-C-Mlt is not a good rotation forAkron and the surrounding area.Planting wheat into proso stubblesoon after harvest results in a verylow soil moisture condition for wheatdue to proso using water relatively

late in the season. During dry years,wheat growth is always severelyreduced. Low wheat residue alsoleads to low corn yields. Soil qualityis overridden by basic rotation designand water usage constraints.Rotations in the study with the mostsubstantial soil quality improvementswere not necessarily the most prof-itable. (Editors: Soil improvementand profitability are not incompati-ble goals, but do require considerableattention to rotation design and pro-duction methods. For instance,choosing crops that finish earlierthan millet—such as field peas oroats—could create improvedsequences, even if these are har-vested for grain or forage instead ofbeing left for green fallow. Peas donot produce much residue, so thesuccess of wheat following peas may

benefits from this sequence, such asdisease suppression and release ofgrowth-promoting substances frompea residues. They suggested thatdry pea could improve nutrient-useefficiency of wheat by improvingwheat root growth.

Plant Diseases & WeedManagement

With the Akron study, sunflowers,corn, and wheat yielded more withlong rotational intervals. (See theSept. ’03 Leading Edge for a com-plete discussion.)

In rotational studies on the GreatPlains, weed densities were reducedby up to 90% in longer, more diverserotations as compared to shorterrotations. Weeds were further disad-vantaged by continuous no-till. (Seethe Dec. ’03 Leading Edge fordetails—it’s worth reading again.)

Sustainability

Scientists and producers have longcontemplated the concept of sus-tainable cropping systems. Alongwith profitability, they recognize thata goal of sustainability centers onprotecting and improving soil qual-ity. In analyzing various approachesto sustainable systems, researchershave suggested redesigning croppingsystems based on ecological princi-ples rather than modifying existingsystems in response to a specificissue.32 Another scientist, reflectingon the history of cropping systemresearch, suggested that a morevisionary approach would prioritizethe design of sustainable systems,then focus research on increasingcrop productivity within that frame-work.33 This approach contrasts withthe historical perspective of empha-sizing productivity of individualcrops without regard to rotationdesign.

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Rotations with the mostsubstantial soil quality

improvements were notnecessarily the most

profitable.

32 S.B. Hill & R.J. McRae, 1995, Conceptual framework for the transition from conventional to sustainable agriculture, J. Sustain. Agric. 7: 81-87.33 E.C. Brummer, 1998, Diversity, stability, and sustainable American agriculture, Agron. J. 90: 1-2.

SoilStructure

NutrientCycling

PlantDiseases

WeedManagement

CropDiversity

ResidueRetention

Sustainability

Ecological Processes

Source:Anderson 2005.

Factors involved in the regeneration of soil with new cropping sys-tems in the central Great Plains. Crop residue preservation improveswater relations, which enables producers to add other crops to thewinter wheat >>fallow rotation. With crop diversity, rotations canenhance various ecological processes related to soil structure, nutri-ent cycling, and pest management, thus improving sustainability ofcrop production practices.

Spiral of Regeneration

Just Say‘No’ toRyegrassRecently in the U.S., consider-able publicity has gone toItalian ryegrass (Lolium multi-florum) as a cover crop.Biotypes of this species areknown to possess resistance toglyphosate, fops & dims, andurea (e.g., diuron) herbicides.Don’t play with this one.

depend on the amount of residueproduced prior to the peas, such aswith W-W-C-Mlt-Pea.)

In the last 70 years, attempts at con-tinuous cropping in this region usu-ally failed because of lack of cropdiversity, inadequate weed manage-ment, and insufficient water.34

However, green fallow (5 to 7 weeksof growth) or forages (8 to 10 weeksof growth) may be a possibility toreplace summerfallow. Legumessuch as dry pea have value for theirN fixation capability. Another optionis oats (Avena sativa), which pro-vides a disease break for winterwheat.35 The choice of green fallowor forage could be based on soilwater and precipitation levels. Thegreen fallow or forage crop wouldcomplete water use early enough toallow moisture storage for wheatestablishment. Some evidence of theviability of this sequence can beinferred from no-till producers near

Akron who have successfullyadopted a W-W sequence within alonger rotation.36

Summary

Extensive soil erosion by wind duringthe 1930s and 1950s led producers todevelop residue retention tech-niques. Later, development of no-tillsystems enabled producers to almosteliminate wind erosion as well asreduce the need for fallow in rota-tions. Rotations such as W-C-Mlt-For W-C-Sf-F now are successful ineastern Colorado and adjacent areas.

It is possible to regenerate soil qual-ity and repair some of the damage tosoil accrued during the decades ofwind erosion and tillage. Soil struc-ture improves with intensive crop-ping that produces large quantitiesof surface residue. Producers viewno-till and continuous cropping asthe next step to continue soil regen-

eration that started with residueretention, reduced tillage, and cropdiversity. As we gain knowledge withbeneficial interactions among crops,we may be able to improve cropsequencing such that continuouscropping will be economically viablein this region to further enhance soilregeneration.

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In the last issue, we described some management strate-gies for tough grass species. While not a grass—althoughoften mistaken for one—nutsedge (Cyperus spp.) is apersistent perennial found in many areas of Kansas. It isdeep-rooted and does well in places with extra moisture,such as ditches, waterways, and draws. A species intro-duced from Eurasia, nutsedge proliferates in poorlymanaged grasslands (the other vegetation isn’t using thedeep water efficiently), and in cropland with long fallowperiods. The sedge exploits these resources.

West of Great Bend, KS, producer Kevin Wiltse fightsnutsedge more than any other species. Controlling it isparticularly critical, since it harbors billbugs that candevastate seedling milo (or corn) in areas where theyfeed. The billbugs overwinter in nutsedge and migrateoutward in search of food in the spring, moving easily0.25 mile or more. Many ragged or thin stands of milo

Nutsedge Control(or corn) blamed on other problems are actually billbugs(a telltale sign is the thin spots correlating to nutsedgepatches approximately, but not quite perfectly due tobillbug migration). Billbugs are extremely difficult toscout and spray in a timely fashion; the most economicalmethod is to kill out the nutsedge.

Wiltse reports good nutsedge control with 40 ozglyphosate + 0.5 oz Classic pre-plant on soybeans. Ifnutsedge pressure warrants, he doesn’t hesitate to go upto 64 oz glyphosate ahead of milo, or in-crop in RR soy-beans. Pre-plant treatments with some suppression ofnutsedge include the acetamides (Dual, Bicep,Guardsman, Harness) and sulfentrazone (Spartan).Don’t expect too much; nutsedge is quite a bit tougherto control than other perennials such as bindweed. Andagain, crop competition is a highly necessary tool.

34 Editors: And yet this region easily supported continuous cropping for the first few decades after theprairies were broke. Soil OM made the difference.

35 S. Lockie, A. Mead, F. Vancaly & B. Butler, 1995, Factors encouraging adoption of more sustainablecrop rotations in south-east Australia: profit, sustainability, risk and stability. J. Sustain. Agric. 6: 61-79.

36 G. Maskus, 2003, Practical Experience with No-Till, in Proceedings: 2003 No-Till on the PlainsWinter Conference (Salina KS, 27-28 Jan. 2003), No-Till on the Plains Inc.

Some are more prone than others, but we all run the riskof ‘buying into’ whatever the latest fad, hype, or buzzmight be. If you hear it often enough, surely it must beimportant and true. Behavioral scientists demonstratejust how conformist we really are.

Controlled traffic seems to be the talk lately. For long-term no-till producers in virtually any region, controlledtraffic is of dubious value. In fact, it might have veryserious consequences long-term that are not noticeableduring the first few years.

‘Controlled traffic’ is where the majority of the loadedtires of the machinery are following the same path in thefield every year, accomplished either with GPS guidanceor ‘old-school’ gaps (tramlines) in the planted crop. Forinstance, the tractor tires, combine tires, and sprayertires might follow the same path (lane) year after year.Since most factory settings on combine and tractor tiresdon’t match up, often some modified version is used.Perhaps the tractor doing the planting and weed controlalways follows the same path, and all those implementsare the same width, or their multiples (20 ft, 60 ft, etc.).

Controlled traffic certainly isn’t new—the idea has beenfloating around for several decades at least. The reason-ing behind it was that those loaded wheels were verydamaging to the soil, causing compaction and restrictingroot growth as well as curtailing the flow of water and airin the soil, and so the damage should be confined to thesame area year after year. The remaining soil between

the lanes would generally be in better condition (untraf-ficked) for growing crops. Also, some tractive efficiencywas gained: since the trafficked paths were driven overrepeatedly and packed into a respectable road, lesswheel slip and horsepower loss occurred. Remember, allthis was conjured in the days of heavy tillage. It was verypopular with ridge-till, since a considerable amount oftillage could be done, yet you could easily find and fol-low the traffic lanes.

Unintended Consequences

A danger lurked in this logic, which wasn’t fully realizeduntil lately. In many agricultural areas ofthe world, largeprecip eventsoccur which can-not be fully infil-trated into the soilduring the shorttime of the event.Some runoffoccurs. Evenunder native vege-tation, such as theprairie, somerunoff occurred.This is why draws,creeks, andstreambeds arepart of the nativelandscape in manyareas. Annual cropping, even in the best rotation in long-term no-till, doesn’t overcome this in most of theseareas. There will eventually be precip events which arenot totally infiltrated. This may be a 10-inch rain in a sin-gle storm, or whatever.

Controlled traffic creates a different infiltration rate inthe repeatedly trafficked lane versus the rest of the field.Remember, it is the ‘sacrifice’ area. The repeated com-pacting of the wheels has left the soil with less structureto move water downward quickly. The wheels have pul-verized much of the surface residue, resulting in surfacesealing during a rain event (see Derpsch’s ‘UnderstandingInfiltration’ in the Dec. ’03 Leading Edge). And less cropresidue is produced in the lane area itself anyway: oftenthe lane isn’t planted to anything (to make it more visi-

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Controlled Traffic, Anyone?by Matt Hagny

Tread carefully. Where you drive—and how often—affects vegeta-tion, mulch, and soil characteristics. For many landscapes and cli-mates, controlled traffic will eventually create massive problems.

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Controlled traffic createswell-traveled lanes whichcannot infiltrate as muchas the rest of the field.

Eventually a precip eventcauses runoff, which

occurs primarily in thelanes. Erosion cuts thelanes down. This will

make them even morelikely to run water the

next time.

Matt Hagny is a consultingagronomist for no-till sys-tems, based in Wichita, KS.T E C H N I Q U E

ble, and/or to economize on seed since it is the ‘sacrifice’area). These effects are cumulative. As the area getsmore and more packed, it grows less and less. As the soilOM is depleted in that lane area (since nothing is grow-ing there, and little residue is returned), it becomesmore vulnerable to compaction. It is a downward spiral.

So the controlled traffic has created areas of the field(the well-traveled lanes) which cannot infiltrate as muchas the rest of the field. Tests have proven this. Eventuallya precip event causes runoff, which occurs primarily inthe lane areas. Erosion cuts the lanes down. This willmake them even more likely to run water the next time abig rain occurs, since some of the best soil (and residue)washed away.

Furthermore, in soils with a significant amount of clay,the repeated driving of wheels over those soils whiledamp causes a ‘marshmallowing’ effect—the soil underthe lane yields and starts to push up the soil nearby.Again, this concentrates water in the lane. It also pre-vents whatever water is ponding in the lane from escap-ing out into the untrafficked area where it might be infil-trated.

If the controlledtraffic field hasany slope at all,the end result isthat you have cre-ated a rill or gullywhere you want todrive. It willinevitably getdeeper, and theproblem will accelerate for the reasons stated above. Theresult is inescapable: if you create differences in infiltra-tion rates in straight lines up and down your hills, andyour region sometimes has large precip events, runoffwill occur which will be concentrated in those lines, cre-ating a gully.1

These processes will occur at different rates in differentlocales, based on frequency of large rainfall events, abil-ity of the local soils to infiltrate water, and slope. Theproblem will become apparent in the loess hills ofKansas and Nebraska before the glacial soils of theDakotas. Areas that never experience runoff will largelyescape the problem (however, the marshmallowing ofhigh-clay soils could still result in deepening tracks andmechanical difficulties, such as on the Darling Downs inQueensland, Australia.)

The argument can be made that steps can be taken toovercome this. For instance, the lane could receive addi-tional chaff or straw from the combine. Perhaps a secondspecies could be seeded into the lane to provide a livingcushion. Now, we are adding further cost and complica-tion. And still, the plants aren’t going to grow as well inthat area. Even a living root system is not impervious todamage. Cattle will beat out a trail in perennial grass.Humans, with only 6 – 8 psi footprints (maybe a fewwith a bit more) and nice spongy rubber-soled shoes, willpound out a trail across a perennial grass park or lawn.My point is that it would take quite a remarkable systemto maintain infiltration in the trafficked area relative tothe untrafficked. My guess is that utilizing the methodsmentioned would slow the process, but the eventual out-come would still be the same (if the area has any poten-tial at all for runoff).

A few will argue that on sloping land, controlled trafficshould be done on the contour. While feasible, I seri-ously doubt it is realistic. The time loss, not to mentioncostly overlaps, almost guarantee the costs will outweighthe benefits.2

Additional Considerations

Somewhat ironically, the reasons for doing controlledtraffic are largely diminished in long-term no-till. As soilsregain structure in well-managed no-till, they are consid-erably less likely to suffer compaction. Organic matter,glomalin, etc. are holding the soil particles in place. Forsimilar reasons, tractive efficiency is greater in no-till.

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Originally the prairies had random traffic by native herds of buf-falo, elk, and other large herbivores. Uneven, isolated, or ‘con-trolled’ traffic, whether by cattle walking single file, mountainbikes on a trail, or ag machinery tires traveling on trams or lanes,will cause lines or areas of soil with reduced infiltration capabili-ties. The result is gullies.

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1 A vivid example is the gullies created by center pivots on steep hillsides—the gullies exactly match up to the paths taken by the pivot wheels. Controlledtraffic at its finest. Note that the problem takes a few years to become obvious, and that it is very difficult (expensive) to remedy.

2 Most soils of N. America have good enough structure under no-till that controlled traffic is of limited value, plus the slopes and rainfall are often such thatcontrolled traffic soon creates huge problems. Australia, however, does have some very low-OM, high-clay soils which exhibit rather high susceptibility tocompaction and therefore would benefit more from controlled traffic. However, managing the erosion in the lanes is still a major issue.

It would take quite aremarkable system to

maintain infiltration in thelanes relative to theuntrafficked areas.

The wheels aren’t sinking in loose destabilized soil.Structured soil gives the tire lugs something to ‘bite.’ Onestablished alfalfa or native grasslands, we don’t worrymuch about causing compaction or getting traction, atleast not to the point of creating controlled-traffic lanes.

Plenty of other problems with con-trolled traffic exist.Machinery mayneed to be modi-fied to get wheelsto line up; thisresults in animmediate cost aswell as possiblefuture costs interms of extrarepairs ordecreased resalevalue. Even worse,it ‘forces’ some decisions into unnatural (i.e., inefficient)outcomes, such as sizing your planter and drill to some-thing other than what they might be if only crop mix andplanting windows were considered. And what if youacquire more land, necessitating slightly wider equip-ment, but not quite justifying double the currentwidth—so either you’re stuck with inappropriate equip-

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ment widths, or you adjust all your lanes and start crop-ping the old abused and eroded lanes.

All told, controlled traffic doesn’t mix well with continu-ous no-till. For nearly all cropland climates and topogra-phies, it is a loser, eventually resulting in massive mechan-ical problems and permanent soil damage that will beextremely expensive to repair or overcome. Controlledtraffic was somebody’s brilliant idea. Unfortunately, it justdoesn’t work out very well in the real world—it looks niftyonly until the 2d or 3d major rainfall event. People whoare invested in the idea, either figuratively or in hard cur-rency, will not want to admit these failures. That, unfortu-nately, is human nature at its worst.

If the producer really wants to take some steps againstcompaction in areas where crops are grown, the answersare out there, and relatively affordable and simple (atleast in comparison with permanent lanes). If continuousno-till is used, about 3/4 of the problem is already solved.Just maximize your residue cover. All that remains to bedone is good footwear for your tractors and combines.Large, wide radial tires at low pressures are by far thebest. Bar-lugs are preferred whenever possible.

So control yourself when deciding how much to con-trol—sometimes a little randomness is in order (punintended).

Somewhat ironically, thereasons for doing con-

trolled traffic are largelydiminished in long-term

no-till. As soils regainstructure in no-till, they

are considerably less likelyto suffer compaction.

Asian Rust Outlook: U.S. PlainsAfter gathering some informationfrom our South American friends,we are convinced that the risk ofSoybean Asian Rust (SAR) on theU.S. Plains is considerablyoverblown. Dirceu Gassen, aBrazilian entomologist by trainingbut widely knowledgeable on manyagricultural topics, explained thatSAR requires 12 – 14 hours of freewater on the leaf surface for infec-tion to occur, and that these condi-tions need to be repeated over aseries of days (~ 15) for the num-bers of spores in a given locale to begreat enough for serious problems.While we have no doubt that SARspores will blow in to the centraland northern U.S. Plains annuallyfrom overwintering sites in southTexas and Mexico, the likelihood ofweather conducive to major prob-

lems seems rather low for KS, NE,and the Dakotas. Gassen also statedthat shorter nights during summer-time in these regions would hinderdevelopment of SAR, just as it doesin northern China and southernBrazil. (Loren Giesler, U.Neb-Lincoln soybean pathologist, haspresented a value of 6 – 8 hrs of leafwetness for infection to occur.)

Further supporting this conclusionare comments by Agustin Bianchiniand César Belloso as to SAR sporesbeing detected in their areas (Rosarioand Pergamino) of Argentina the last2 seasons, blown in from Brazil.However, those areas of Argentinahave yet to develop any noteworthyoutbreaks of SAR. This, despite thoseareas of Argentina being closer to the

equator (longer nights in summer)and having more rainfall and humid-ity than most of the U.S. Plains. Forinstance, the Argentinean area men-tioned would have summertimenights 20 – 30 minutes longer thanKS. Humidity, a very rough indicatorof moisture conditions, again shows asmaller likelihood of problems: com-paring similar seasons (Aug. in theU.S. is equivalent to Feb. inArgentina), the average humidity atRosario being 65% compared to 59%for Wichita, KS.

While we cannot say these areaswon’t have problems with SAR, wethink all things considered, it’s notgoing to be a chronic productionproblem for soybeans on the U.S.Plains.

Grace Under Pressure by Roger Long

Stan Miller has beenfarming in DecaturCounty ever sincehe can remember.Stan’s optimismand never-say-dieattitude permeate allwho come into contact with him.After meeting Miller, one wouldthink he’s had it pretty easy over theyears and everything is rosy, butfarming in northwest Kansas thepast few years has been no picnic.With extended periods of dryness insome years and full-fledged droughtin others, growers there have seenmore than their fair share of failedcrops. While no-till still can’t pro-duce grain in the complete absenceof moisture, it gives growers the bestchance of salvaging some semblanceof yield. “No-till has been my onlysaving grace,” quips an embattledyet cheerful Miller.

Stan’s area received a little less thanhalf its ‘normal’ annual rainfall in ’02and ’03. Half of 22 inches doesn’t govery far. Exacerbating the situationhas been the less-than-ideal timingof moisture arriving in recent years.

Stan was only a little behind averagefor rainfall by the end of 2004, butbecause so much came so late hiscorn only averaged 48 bu/a with ahigh of 65. In 2003, he grew 60-bu/awheat that was planted into cornstubble that didn’t make enough ingrain in ’02 to warrant harvesting. Inthis part of the world, capturingevery drop of moisture—no matterhow fast or slow it comes—is so very critical.

Then, protecting that moisture fromevaporation once it’s in the soil.Fortunately, a residue thatch accom-plishes both.

The inescapable facts of moistureconservation in such a low-rainfallarea tugged at Miller from hisbeginnings. “I started farming in

1977 and tried a littleno-till my first year. Afew farmers aroundhere were trying awheat >>milo >>fal-low rotation, and Iliked the looks ofmilo coming upthrough the wheatstubble. . . . Withthat rotation, wecould plant another16 or 17% of ourland [beyond the50% planted inwheat >>fallow]. Wewere making more

on our row crops than on our wheat.It was a tremendous spike in cropyields for that era.” That success setStan on the path toward eventuallypurging the tillage during summer-fallow, and then eliminating the fal-low itself. By ’94, Miller was 100%no-till and hasn’t performed anytillage since.

Miller recalls early ‘ecofallow’ pro-ponent Gail Wicks teaching much ofthe equipment methodology nowemployed in his current no-till sys-tem—“Wicks was doing research inwestern Nebraska and would comedown and give presentations here.”Getting openers to cut throughresidue and getting good seed-to-soil contact were his toughest obsta-cles. “I really had the most problemswith planter set-up in those earlyyears.” Diligent about detail, Millerwould sharpen opener blades afterjust one season of planting and thenreplace them after the second. “Ireally need the mulch up around theplant, so I don’t push residue to theside—I’ve got to cut through it.Sometimes it just takes patience,like waiting a little while longer inthe morning to start planting—sothe residue isn’t as tough.”

How the Pieces Fit

As with many longtime no-tillers,Miller sees numerous improvementsin soil quality that translate intoincreased productivity. “Soil OM isbetter, water infiltration is better,erosion is way down, and the fieldssupport my equipment better too.”An additional benefit has been asubstantial reduction in pH—andwhen you start in the high 7s andlow 8s, that’s a good thing! Strollingacross Miller’s fields, residue is visi-

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Stan’s wheat in soybean stubble, fall of ’04. Wheat after soy-beans is a tight sequence in his dry climate.

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“We weren’t gettingenough wheat stubble togrow a good corn crop.Stacked wheat lets meaddress that situation.”

ble everywhere—and Stan rattles offhis previous crop sequence, mir-rored on the soil surface by the rem-nants of past crops.

Miller has found that no-till provideshim the opportunity to have diversecrops growing year-round in an areawhere tillage only allows summerfal-low >>wheat. Always having some-thing growing has in turn given himthe best chance to convert erraticrainfall into grain (of one sort oranother) whenever it occurs. Hisrotations evolved into a wheat, corn,and soybean mix with only a third ofhis acres in wheat in any one year.Due to recent droughts andother rotational

adjustments, he hasn’t settled in onan exact rotation but it normally fol-lows a wheat >>corn >>soybeanpattern. He plans to implementsome stacks where they fit. “I’vedone a little stacked wheat over theyears, mostly to even out rotations,but never made it a practice. Afterhearing others’ success with it, Iwent with quite a number of acresof stacked wheat this year. Weweren’t getting enough wheat stub-ble to grow a good corn crop.

Stacked wheat lets meaddress that situation.”

In Stan’s crop line-up,noticeably absent issorghum. Miller grewmilo in the early ’80sbut was having troublegetting it to finish—“Our elevation is 2,680feet which can makeour nights fairly cool.”Those cool nights arebeneficial for corn, butnot so great for milo.Couple that with thesoil temperature dif-ferences for germination of corn vs.milo, and corn has the advantage.Stan hasn’t grown milo on his farmsince 1986. It’s hard to argue withresults—for such a low-rainfall envi-ronment, Miller has impressive cornyields. While eastern Kansas pro-ducers would consider Miller’s aver-age annual rainfall (22 in/yr) adrought, Miller routinely shoots for80 to 120 bu/a (depending upon soildepth), and produced 150-bu/a cornin the late ’90s. He had a provenaverage of 90 bu/a before the’02–’03 drought. Despite thedrought, Miller is as committed asever to corn, and plans to try stack-ing it.

Miller added soybeans to his rotationin 2000, just when the dry years hit.“I think the beans will work, givenaverage rainfall.” Despite using 2.6-to 3.1-maturity soybeans, they still

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Close-up of Stan’s wheat.

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With no-till, “Soil OM is better,

water infiltration is better,erosion is way down.”

The Stan Miller farm finishes up wheat seeding.

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only get done a couple weeks beforewheat seeding must occur. This is atight sequence, and sometimes thewheat lies in the dust. Stan recog-nizes the problem, and is mullingways of overcoming it. He isintrigued with crops such as wintercanola or brown mustard that wouldfinish earlier than soybeans.

Additional Diversity

Miller continues to adapt his meth-ods based on experience and knowl-edge at hand. Variable weatherforces Miller to manage risk with awide range of planting dates foreach crop, and wheat managementis affected the most. Miller is quickto recognize and account for the dif-ferences in tillering from variouswheat planting dates. Starting inmid-September and aiming to bedone by mid-October, he beginsdrilling with around 1.2 millionseeds/a, and later ups his rates to 1.6million seeds/a (approx. 2.0 bu).Fertilizer rates normally run around85 lbs of N (60 units pre-plant andanother 25 units in a top-dress appli-cation), 25 lbs of P (P2O5), 10 lbs ofS, and 0.5 lbs of Zn, but each field isfine-tuned based upon soil tests.

Stan seems well-versed in herbicidechoices and performance—“I’venever had too much trouble withthe chemical part of it.” Glyphosatehas always been an integral compo-

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nent of Miller’s weed control, evenwhen it was four times today’s price.While many growers have slid intoheavy reliance on glyphosate as theironly active ingredient, Stan and hisServi-Tech consultant, James Bieker,employ numerous products withdiverse modes of action. Miller rou-tinely utilizes fall applications ofatrazine for fields going to corn, anduses pre-emerge Bicep for in-cropresidual control. Post-emerge prod-ucts are used as necessary, and fortough problems like grassy sandbur(only 20 to 30% of his acres), Millerdoes use glyphosate for over-the-topapplications in RR corn in thosetroublesome fields.

Miller also operates a 1,500-headbackgrounding feedlot. He takes 300– 400 acres of corn each year forsilage, then uses those same fields fordispersing manure from the lots.Recognizing the void of residue fromharvesting the entire plant,“Wherever I take a field for silage, Ialways plant wheat right away to getsomething back on those fields.”Stan’s feedlot also enables him to mixsome variance into his rotation byplanting oats and triticale and thenhaying those crops for the cattle.Miller is careful about residueremoval. Prior to selling his cow herdin ’01, Stan did graze some corn

stalks but thought this caused prob-lems with plantability and yield in thefollowing soybean crop. “I surewouldn’t rent the stalks to anybody.You’re not getting paid enough.”

No-till not only allows Miller to cropevery acre, every year, but the wearand tear on both man and machinehas been minimized. Miller putsfewer hours per year on enginessince he’s eliminated all thosedestructive, repetitive tillage trips.And the hours required for no-tillare under reduced load and easieron equipment. “When we were stilldoing some tillage, I would figure8,000 hours before I needed totrade tractors. Now, it looks like I’llget at least 12,000 hours.”

It’s tough to keep good things asecret. With Stan, it’s evident hewants to spread the good fortunes ofno-till to anyone who will listen. Hehas been instrumental in the north-west Kansas ‘Cover Your Acres’organization that has hosted manyno-till field days and meetings, allwith tremendous commitment oftime and resources by Miller. No-tillprovides Miller with a competitiveedge, but his desire to help othersand improve the sustainability of theregion keeps pushing him to pushthe masses. Such an optimistic char-acter as Miller continually focuseson progress, visualizing the brightfuture of the possible.

Stan’s wheat stubble, all set for corn in 2005.

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