Presented by Vance Owens, Director of North Central Sun Grant Center, South Dakota State University on December 8, 2014 at Minnesota Bioenergy Feedstock Development meeting and forum.

1. Opportunities to practically scale-up
perennial feedstocks
Vance N. Owens (and many others)
North Central Sun Grant Center
South Dakota State University
University of Minnesota, 8 Dec. 2014

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

3. The Prairie Farm Story

4. 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 hillslopes
each with 2
transects
Sample depth : 0‐15 cm
4 hillslope positions
One Way ANOVA with
Bonferroni Correction
Statistical Analysis

5. 0 50 100 150 200
Footslope
Midslope
Upper
Shoulder
Summit
Cultivated Uplands
POM
SOM
FDA
WAS
POM (g/kg) SOM(g/kg); FDA (µg/g) WAS (%)
0 50 100 150 200
Footslope
Midslope
Upper
Shoulder
Summit
Prairie Remnant Uplands
POM
SOM
FDA
WAS
POM (g/kg) SOM(g/kg); FDA (µg/g) WAS (%)
Heimerl, 2011

6. 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

7. 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

8. EcoSun Prairie Farms, Inc.

9. 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

10. In the beginning…

12. Products

13. Products

15. Farm‐scale (left) and small plot (right)
yields a the Prairie Farm
Field‐scale harvest of native grasses
Year Species Season
Yield
(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

16. 15 different species of pollinators (bees, flies, and beetles) recently recorded at Brookings.
Some other benefits…

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

18. Resapamea stipata
(Lepidoptera: Noctuidae)
Four‐lined borer

19. Healthy tillers (lt.) and tillers killed by R. stipata (rt.); Brookings, Sept. 2011
~40% infestation rate
Infested tiller mass ~ 40% of
normal tiller mass

20. • 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 monocultural
agroecosystems
Switchgrass Gall Midge
Chilophaga virgati

21. `Cave‐in‐Rock’ Impact
4 yr old exemplar from Aurora, SD,
September 2012
Tillers:
N = 38
Normal = 21 55%
Midge infested = 17 45%
35% biomass reduction
12.7‐14.3% infestation rate among
10 genotypes
Boe & Gagné (2011)

22. Soil and Water Quality

23. Manure utilization on switchgrass (Lee et al., 2007)
2001-2002 2003-2004
N 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

24. 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)

25. 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

26. 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
Soildepth(cm)
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
Soildepth(cm)
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

27. 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.
NO3concentration(mgL-1)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
N 0 kg N ha-1
N 56 kg N ha-1
N 112 kg N ha-1
NS
LSD=0.47
LSD=0.58
LSD=1.02
LSD=1.11
2009
Month
Aug. Sep. Oct.
NO3concentration(mgL-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.
NO3concentrationinleachate(mgNL-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
NS
LSD0.05=0.14
NS
NS
LSD0.05=0.08
LSD0.05=0.08
2012
Month
May Jun. Jul. Aug.
NO3concentrationinleachate(mgNL-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=0.16
NS
NS