Managing warm-season grasses for pasture and bioenergy in the Prairie Peninsula

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1 Managing warm-season grasses for pasture and bioenergy in the Prairie Peninsula Laura Paine Southwest Badger RC&D

2 Cellulosic bioenergy development is a classic chicken and egg problem. The supply side won t produce until there is sufficient demand. The demand side won t invest until there is sufficient supply.

3 Forage production can provide the needed bridge

4 Ecological Context: maximizing the environmental benefits of bioenergy

5 Ecological context Some ecological and socio-economic considerations for biomass energy crop production. In Biomass and Bioenergy 10/4: Avoid feedstocks with environmental liabilities: Municipal wastes Crop residues Standing forests Annual energy crops

6 Ecological context Some ecological and socio-economic considerations for biomass energy crop production. In Biomass and Bioenergy 10/4: Promote feedstocks that provide environmental co-benefits: Waste wood Dedicated perennial energy crops Short rotation woody crops (e.g. hybrid poplar) Herbaceous crops (native and non-native grasses)

7 Siting perennial bioenergy crops to maximize environmental benefits Some ecological and socio-economic considerations for biomass energy crop production. In Biomass and Bioenergy 10/4: Highly erodible land Getting perennial cover on sloping land Previously drained wetlands Returning currently cropped wetlands to perennial cover Controlling invasive reed canarygrass through annual harvests Other marginal ag land SRWC on forest soils

8 Herbaceous bioenergy crops Some ecological and socio-economic considerations for biomass energy crop production. In Biomass and Bioenergy 10/4: Benefits of grasses for bioenergy: Carbon storage Reduction of soil erosion Water quality improvement High quality wildlife habitat

9 Grassland bird declines associated with intensification of agriculture Acres X Forages Rowcrops Western Meadowlark # Birds/Survey

10 Grassland bird use of agricultural land Tilled Corn No-till Corn Alfalfa Continuous Pastures Rotational Pastures Idled Paddocks CRP Total Nests Estimated Nest Survival

11 Habitat quality of biomass production fields Grassland bird response to harvesting switchgrass as a biomass energy crop. In Biomass & Bioenergy 28: Does harvesting for biomass energy affect habitat quality of native grasslands for ground-nesting birds? We harvested CRP switchgrass fields in August. We measured grassland bird populations using harvested and unharvested fields the following summer.

12 Species Richness in harvested and unharvested plots Short Grass Species Mid-Grass Species Tall Grass Species Harvested Unharvested

13 Greater species abundance in harvested plots Upland Sandpiper 2 Western Meadowlark Grasshopper Sparrow 1.5 Eastern Meadowlark Bobolink 1 Dickcissel Northern Harrier 0.5 Henslow's Sparrow 0 Harvested Unharvested Sedge Wren

14 Harvest effects on grassland birds Grassland bird response to harvesting switchgrass as a biomass energy crop. In Biomass & Bioenergy 28: Harvesting in August allowed time for some regrowth and improved habitat quality the following spring. Harvesting increased abundance and species richness of short grass and mid-grass bird species. Abundance and species richness of tall grass species were higher in unharvested switchgrass fields.

15 We still need perennial crops for sensitive soils in the upper Midwest Illinois Iowa Minnesota Wisconsin 0% 20% 40% 60% 80% 100% Class I & II Class III Class IV-VI

16 Perennial Forage Working Group one of five GLBW working groups Mission: To increase acreage of pasture and perennial forage crops in the Upper Midwest To encourage best management practices in existing pastures. We work to: Identify obstacles currently facing grazing operations and perennial forage production Develop & support economically sustainable strategies, tools &services to increase pasturelands and perennial forages.

17 Declines in cropland pasture acres 2,500,000 2,000,000 IL IA MN WI acres 1,500,000 1,000, ,

18 Implications for Continuous Living Cover Fewer, larger livestock farms Fewer producers raising forages Forage production concentrated in discrete areas Fewer opportunities to grow forages for sale (markets less accessible) Fewer opportunities for manure sharing

19 Why use Warm Season Grasses? Cool Season Paddocks Warm Season Paddocks Complements cool-season pastures Drought tolerance Heat tolerance Low input: reduced costs

20 Challenges for Farmers Slow establishment. High priced seed. Competition from non-native cool season grasses. Lack of data on appropriate management.

21 Incorporating Native Warm Seasons into Livestock Systems Tradeoffs in Performance of Native Warm-Season Grass Cultivars and Locally Harvested Seed Managed for Wildlife Habitat or Livestock Production. In: Agronomy Journal, 104:5, 2012 Research Questions Comparing Named Cultivars and Local Ecotypes Which are better adapted for pasture use (longevity, drought tolerance, etc.)? Which provide higher yield or quality? Comparing grazing timings Development/early grazing starting in early June based on forage quality objectives. Calendar grazing after July 15th based on wildlife habitat objectives.

22 Experimental Design Native grass seed mixes planted in 2007 Prescribed fires annually in spring Graze treatments first applied in June 2009 Graze Development Treatments - MIG, grazed in June and mid-july Development Replicate 1 Calendar Calendar - Conservation, grazed in mid-july and September Seed Ecotype Treatments - WCIA certified native grass ecotype seed, South Central WI Variety Ecotype Ecotype Variety Variety strains selected for agronomic traits in North & South Dakota

23 Management Plots were rotationally grazed by cow-calf pairs or feeder steers. Each plot was grazed for approximately 90 Animal Unit Days each season, achieved by adjusting the grazing time. The entire field was burned each year in spring prior to the first grazing.

24 Ecotype vs. cultivar yields lb/ac a b a a Ecotype Cultivar a b a b a b Average

25 No differences in forage quality between ecotypes and cultivars Relative Forage Quality Ecotype Cultivar Crude Protein Ecotype Cultivar Eco Local ecotype C4 grass seed mix: Big bluestem, Indian grass, Switchgrass, Sideoats grama, Canada wildrye, Little bluestem. Var Non local C4 grass seed cultivars/varieties : Bison big bluestem, Tomahawk Indian grass and Sunburst switchgrass.

26 Grazing Timing Results Development Graze: June & July Calendar Graze: July & September

27 Seasonal Forage Availability Development Graze Calendar Graze Calendar graze seasonal average: 9660 lb/a a b a b Development graze seasonal average: 5725 lb/a June July September

28 Seasonal Forage Quality: RFQ a Development Graze Calendar Graze Development graze seasonal average: 128 b a a Calendar graze seasonal average: June July September

29 Seasonal Forage Quality: CP Development Graze Calendar Graze a Development graze seasonal average: 11.7% b a Calendar graze seasonal average: 7.9% a 0 June July September

30 Summary Development graze Lower yields Higher protein Higher RFQ Calendar Graze Higher yields Lower protein Lower RFQ Yield decline Ecotype vs. Cultivar Ecotype had higher yields No difference in forage quality

31 Final thoughts Maximize ecological benefits Siting considerations Grassland bird habitat/harvest schedules Soil erosion/water quality Blending forage and bioenergy production Local ecotypes vs. cultivars Biomass yield, forage quality, and harvest schedules