Planting and Care of Young Pecan Trees

Lenny WellsUniversity of Georgia

Tree Types• Container grown

– Plant late September or early October is best

– Plant while dormant works well

– Spring planting less successful

• Bareroot– Plant while dormant:

January - March

Planting Too Deep

• Most common cause of problems with young pecan trees– Trees unable to develop adequate brace roots

When a tree is grafted below soil line, an artificial planting depth discoloration is created when soil is mounded back, and trees are replanted to this depth “the depth they grew in the nursery”. They often then sink further as soil settles.

Pecan, roots won’t readily develop from the mature-wood grafted top.

So major roots needed for anchorage cannot develop except underground several inches, where their effectiveness is greatly diminished.

Why are trees commonly planted too deep?

Bill Goff

• Planting Depth

– Better to plant too shallow than too deep

– Highest lateral root even with or just under soil line

Planting

• Bareroot: prune root to 18 inches, remove lateral roots; prune top by 1/3-1/4.

• Container: prune any wrapped roots at container bottom

30” 20” 10” Root length at planting

Tree survival & growth depends on new root development, not the existing root system. New roots develop from the cut surface. More important in tighter soils.

Root Pruning

Planting• Do not allow tree roots to dry out• Heal-in for long term

– Keep roots moist and covered in field

• Dig with 18” auger, deep enough to hold root system

• Fill hole with same soil• Fill hole ¼-1/2 full of water, add dirt

into the hole • Pack soil, but do not compact• Protect trunks from sunscald &

herbicide– Trunk wraps/guards– White latex paint

• Prune top back by 1/3 to ¼– Faster rate of growth & more

vigorous– Leave 2 buds

What size tree should I plant?

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Wood, 1996

THE TWO MOST IMPORTANT FACTORS IN YOUNG TREE SURVIVAL & GROWTH

• Eliminate Weed Competition

• Adequate irrigation

Vegetation-free Distance in Bermudagrass Sod• ‘Kanza’ on Giles rootstock• Bareroot whips ≈ 6 ft tall• Irrigated as needed with solid-

set sprinkler• Circles maintained vegetation

free with glyphosate, entire area treated with Surflan

• Results– No effect 1st & 2nd year– 3rd year largest tree in 3 – 24 ft

vegetation-free circle– 4th year largest tree in 6 – 24 ft

vegetation-free circle– 5th & 6th largest in 24 ft

vegetation-free circle

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Mike Smith

YIELD• Token yield in the 5th & 6th

growing seasons.– 5th year 6 ft or greater

produced most yield– 6th year 24 ft dia most yield

• 7th growing season 18 lbs/tree (1089 lb/a; 20’x35’ spacing) with 24 ft dia.

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Mike Smith

What Herbicides are Safe to Use Around Young Trees?

• Postmergence:– Glyphosate or Paraquat ---burndown– Sandea---nutsedge, pigweed, wild radish– Aim---pigweed/morning glory– Basagran—some broadleafs and yellow nutsedge– Poast---annual and perennial grasses– Select---annual/perennial grasses– Fusilade---annual/perennial grasses

• Pre-emergence:– Surflan– Prowl– Chateau

Irrigating Young Trees– Drip

• Most efficient water application method.• Need to cover about 50% of the root zone

with water.• Can apply nitrogen through the irrigation

system.• Requires excellent filtration.• Requires treatment for microorganisms

to avoid stoppage if water source is surface.

• Can be automated.

– Microsprinkler• Less efficient water application than drip,

but acceptable.• Can cover most of the root zone.• Requires good filtration, but not as good

as drip.• Can be automated.

1st year trees4hrs every other day (8 gph emitter) Budbreak through September

Protecting Young Trees From Pests• Budbreak:

– Pecan budmoth (chlorpyrifos)– Phylloxera (imidacloprid,

chlorpyrifos)– Boring Beetles (chlorpyrifos)– Asian Ambrosia Beetle (permethrin)

• Budbreak – July: – Leaf hoppers (imidacloprid,

chlorpyrifos) – Thrips (chlorpyrifos)

• June-September: – Walnut caterpillar, Fall webworms

(chlorpyrifos, pyrethroid)

Leafhopper Damage

Pecan BudmothDamage

Walnut caterpillar

Deer Protection• Two ways to

protect trees from deer:– Repellants– Elimination

Garlic Oil DispenserBag of 50: $29.25Bag of 250: $111.40www.gemplers.com

Will remove large bucks for free

Fertilization

• Year 1:– No fertilizer until May/June– ½ lb 10-10-10– Apply Zinc Sulfate at 1 lb per

tree for the 1st 3 yrs.– 2-3 sprays foliar Zn – Mouse Ear Trees:

• Apply Ni at rate of 1.5 qts/100 gallons or

Effect of Temik on Young Pecan TreesSeedling Shoot Length

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Effect of Temik on Young Pecan Trees

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Cape Fear

Sumner

Elliott

First Year Orchard Establishment Costs

Item Unit Quant. Price $ Per acre

lime Ton 1 30 30

Fert lbs 12 3.33 39.96

Zinc lbs 24 0.35 8.40

Herbicide Appl 3 29.25 87.75

Trees Tree 24 15 360

Labor hrs 20 7 140

Irrigation (oper.) 1 13 13

Irrig. Install. acre $630

Spray Material acre 2 15 30

Note: Irrigation Installation does not include pump Total $1339.11

Costs based on 30 X 60 spacing = 24 trees per acre

Questions?