Fertility Issues in Switchgrass Production

Fertility Issues in Switchgrass Production

Joint Meetings of SERA-ieg 6, NEC-17 and NCRA-13

2008

Nashville, Tennessee

Donald Tyler

University of Tennessee

DOE UT Switchgrass Project

Burt English (Co-director)

Daniel DeLaTorre Ugarte (Co-director)

Chris Clark

Clark Garland

Ken Goddard

Kim Jensen

Roland Roberts

Larry Steckel

Donald Tyler

Marie Walsh

Sources of Ethanol in USA

• Corn – starch based

• Sugarcane – sugar – (Brazil)

Corn – limited suitable land

- competes for corn as food

- high inputs

- FFE of 1.1 to 1.2 to 1

Cellulosic Ethanol

• Wood wastes (expensive)• Corn and wheat stover (limited)

• Crops:• Switchgrass (Panicum virgatum) FFE

5.2 to 1• Giant miscanthus • Hybrid poplar (North USA)

Status

No surplus or production advantage for corn or soybean production in TN. Our competitive advantage is perennial switchgrass.

Thrust for cellulosic ethanol production and use at national and state level.

Lack of efficient switchgrass production strategies in TN.

Switchgrass

Perennial

Relatively low input crop

Other species & biomass sources

Competitive advantage in the Southeast

Native species

Planted with seed

No specialized planting or harvesting equipment

Dedicated Energy Crops -- 2010

Dry Tons

zero

up to 500 thousand

up to 1 million

up to 2 million

up to 4 million

over 4 millionEstimated using POLYSYS analytical system, Daniel De La Torre Ugarte and Burton English

Dedicated Energy Crops -- 2020

Estimated using POLYSYS analytical system, Daniel De La Torre Ugarte and Burton English

Dry Tons

zero

up to 500 thousand

up to 1 million

up to 2 million

up to 4 million

over 4 million

160 million tons of

switchgrass from 19

million acres

Dedicated Energy Crops -- 2030

Dry Tons

zero

up to 500 thousand

up to 1 million

up to 2 million

up to 4 million

over 4 millionEstimated using POLYSYS analytical system, Daniel De La Torre Ugarte and Burton English

362 million tons of

switchgrass

from 35 million acres

Research in Progress

Soil / landscape suitability Seeding / nitrogen rate

interactions Cultivar selection Weed control strategies On – farm demonstrations

Switchgrass production:

Seeding Rate – Nitrogen Study

Nitrogen rates: 0, 60, 120, 180 lbs. N per acre as NH4NO3.

Spring applied starting the 2nd season.

Seeding rates: 2.5, 5.0, 7.5, 10.0 and 12.5 lbs. PLS per acre.

Alamo variety

Nitrogen

• Being evaluated

• Responses vary

• Presently 60 lbs. N/A after first year

Seeding Rate 60 lbs.

N/A

11.0 a

10.0 a

10.1 a

11.5 a

9.6 a

11.3 ab

10.6 ab

12.6 a

10.5 b

10.5 b

DM Yield in T/A

Lbs./ A PLS

2.5

5.0

7.5

10.0

12.5

2006 Well drained to moderately well drained level upland

180 lbs. N/A

0 lbs. N/A

8.5 a

9.4 a

8.9 a

9.2 a

7.7 a

120 lbs. N/A

10.8 a

10.7 a

11.3 a

10.7 a

10.0 aValues within a nitrogen rate followed by the same letter are not significantly different at P = 0.05<

Seeding Rate 60 lbs.

N/A

2.4 b

4.6 a

4.5 a

4.8 a

3.8 ab

5.1 b

6.8 a

7.2 a

7.2 a

7.0 a

DM Yield in T/A

Lbs./ A PLS

2.5

5.0

7.5

10.0

12.5

2006 poorly drained floodplain

180 lbs. N/A

0 lbs. N/A

2.6 b

3.1 ab

3.0 ab

3.4 ab

3.8 a

120 lbs. N/A

4.0 a

5.2 a

5.0 a

5.4 a

5.2 aValues within a nitrogen rate followed by the same letter are not significantly different at P = 0.05<

Phosphorus

• Removed tissue concentration ( 8 locations over 5 years) 0.09% P

• 8 tons to the acre = 14 lbs P/A or

32 lbs P2O5

• Low testing (Mehlich 1) = 40 lbs P2O5/A

Potassium

• Removal tissue concentration (8 locations over 5 years) 0.52% K

• 8 tons/A = 83 lbs K/A or 100 lbs K2O/A

• Low testing (Mehlich 1) = 80 lbs K2O/A

Soil Acidity

• No lime recommended pH 5.0 and above

• O. M. complexing Al and Mn

Summary

Establishment – 6 lbs./A PLS – Tilled or no-tilled ½ inch or less coverage.

Fertilization – 60 lbs./A N after 1 year – 40 lbs./A P2O5 & 80 lbs./A K2O at low soil test.

Weed Control – Broadleaf available – Grass control in process.

Harvest – Big round or square bales – Modules? – Stack storage? – In field processing?