Opportunities to practically scale-up perennial feedstocks

Vance N. Owens (and many others)North Central Sun Grant CenterSouth Dakota State University

University of Minnesota, 8 Dec. 2014

Issues

• Species (multiple and multiple use)• Time• Establishment• Cost• Insects• Weeds• Land/soil (marginal??)• Productivity• Market

The Prairie Farm Story

Hillslope – EcoSun Farm

Hillslope – Sioux Prairie – Nature Conservancy Prairie Remnant

Comparisons between Cultivated and Prairie Remnant

Prairie Remnant  is 3 kilometers from EcoSun Farm

Similar soil catena, slope grade   Upland : Egan, Ethan (Haplustolls, Calciustolls)Wetland : Baltic, Worthing(Endoaquolls, Argiaquolls)

2 fields each with 4 transects

2 hillslopeseach with 2 transects

Sample depth :   0‐15 cm4 hillslope positions 

One Way ANOVA withBonferroni Correction

Statistical Analysis

0 50 100 150 200

Footslope

Midslope

UpperShoulder

Summit

Cultivated Uplands

POM

SOM

FDA

WAS

POM (g/kg) SOM(g/kg); FDA (µg/g) WAS (%)

0 50 100 150 200

Footslope

Midslope

UpperShoulder

Summit

Prairie Remnant Uplands

POM

SOM

FDA

WAS

POM (g/kg) SOM(g/kg); FDA (µg/g) WAS (%)Heimerl, 2011

0 50 100 150 200

Low Point

Mid Point

High Point

Cultivated Wetlands

POM

SOM

FDA

WAS

POM (g/kg) SOM(g/kg); FDA (µg/g) WAS (%)

0 50 100 150 200

Low Point

Mid Point

High Point

Prairie Remnant Wetlands

POM

SOM

FDA

WAS

POM (g/kg) SOM(g/kg); FDA (µg/g) WAS (%)

Heimerl, 2011

Summary

• 40% reduction in SOM in the past 100 years• Distribution of SOM across hill slopes under cultivation

suggests significant erosion in the past 100 years• Decreased carbon recycling and structural stability

(reduced FDA, lower POM, lower WAS) at the cultivated site

• 60% reduction in SOM observed in cultivated vs. prairie remnant wetlands

• Bottom Line: The cultivated landscape has significant potential for rehabilitation/restoration

EcoSun Prairie Farms, Inc.

Prairie Farm Experiment

• 650 acre row crop farm near Brookings converted to native grassland and restored wetlands

• Started in 2008• Goal to determine the environmental

improvements and economic viability of “commercial” grassland grown on cropland soils

In the beginning…

Products

Products

Farm‐scale (left) and small plot (right) yields a the Prairie Farm

Field‐scale harvest of native grasses

Year Species SeasonYield

(Mg/ha)Area (ha)

2010 BB mix Summer 4.9 23

2011 BB mix Summer 4.5 8

2011 BB/SW Autumn 6.2 43

2012 BB mix Summer 3.8 13

2012 BB mix Autumn 4.2 36

2012 SW Autumn 5.8 23

2012 PCG Autumn 8.3 0.4

15 different species of pollinators (bees, flies, and beetles) recently recorded at Brookings.

Some other benefits…

Switchgrass response to N over 3‐4 years at five locations in the US (Hong et al. 2014)

Resapamea stipata(Lepidoptera: Noctuidae)

Four‐lined borer

Healthy tillers (lt.) and tillers killed by R. stipata (rt.); Brookings, Sept. 2011

~40% infestation rate

Infested tiller mass ~ 40% of normal tiller mass

• 0‐100% tillers/plant infestation rate• 40‐60% biomass production loss• Malformed Inflorescence is lost biomass• 100% seed loss per tiller• Induced bivoltinism – Extended activity period in 

response to multiple cultivar mixtures• Limited restraints on population growth – Reduced 

predator and parasite loads due to monoculturalagroecosystems

Switchgrass Gall MidgeChilophaga virgati

`Cave‐in‐Rock’ Impact4 yr old exemplar from Aurora, SD, September 2012

Tillers:  N = 38Normal = 21  55%Midge infested = 17 45%

35% biomass reduction12.7‐14.3% infestation rate among 10 genotypes 

Boe & Gagné (2011)

Soil and Water Quality

Manure utilization on switchgrass (Lee et al., 2007)

2001-2002 2003-2004N source & rate Total SW Total SW

---------------- Mg ha-1 ----------------0N 5.6 5.0 6.3 5.1 112N 8.5 6.5 10.1 5.9 112M 9.7 8.9 9.7 7.6 224N 8.8 6.1 10.1 5.3 224M 7.8 6.4 10.5 7.5 LSD (0.05) 2.3 2.1 2.6 NS

Nitrate-N loss over four years in MN(data from Randall and Mulla, 2001)

0

50

100

150

200

250

Continuous corn Corn‐soybean Alfalfa CRP

Nitrate‐N loss (kg ha

‐1)

Increased runoff and erosion are the leading causes of stream impairment in USA

Transport of sediments to streams/aquifers affect water quality in agricultural watersheds

33

Water Quality and Runoff Problems

Switchgrass root biomass at various depths one and three years after establishment (Bristol, SD)

2011

0.0 0.5 1.0 1.5 2.0 2.5 3.0

Soil

dept

h (c

m)

0

15

30

45

60

100

NS

NS

NS

2009

Root biomass (Mg ha-1)0.0 0.5 1.0 1.5 2.0 2.5 3.0

Soil

dept

h (c

m)

0

15

30

45

60

100

N rate 0 kg N ha-1

N rate 112 kg N ha-1

NS

NS

NS

NS

NS

NS

NS

Monthly NO3 concentration in leachate collected from lysimeters placed 1 m deep in a switchgrass stand in northeastern SD (2009-2012)

2010

Month

Jun. Jul. Sep. Oct. Nov.

NO

3 co

ncen

trat

ion

(mg

L-1 )

0.00.51.01.52.02.53.03.54.04.55.0

N 0 kg N ha-1N 56 kg N ha-1N 112 kg N ha-1

NSLSD=0.47

LSD=0.58

LSD=1.02

LSD=1.11

2009

MonthAug. Sep. Oct.

NO

3 co

ncen

trat

ion

(mg

L-1 )

0

1

2

3

4

5

6

7

8

N 0 kg N ha-1

N 112 kg N ha-1

NS

NS

NS

2011

Month

May Jun. Jul. Aug. Sep. Oct.NO

3 co

ncen

trat

ion

in le

acha

te (m

g N

L-1

)

0.0

0.4

0.8

1.2

1.6

2.0

0 kg N ha-1

56 kg N ha-1

112 kg N ha-1

NSLSD0.05=0.14

NS

NS

LSD0.05=0.08

LSD0.05=0.08

2012

Month

May Jun. Jul. Aug.NO

3 co

ncen

trat

ion

in le

acha

te (m

g N

L-1

)

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

0 kg N ha-1

56 kg N ha-1

112 kg N ha-1

NS LSD0.05=0.16NS

NS