Proceedings available at: http://www.extension.org/67680 As a major contributor in food production, beef production provides a major service to our economy that must be maintained. Production of cattle and the associated feed crops required also impact our environment, and this impact is not well understood. Several studies have determined the carbon footprint of beef, but there are other environmental impacts that must be considered such as fossil energy use, water use, and reactive nitrogen loss to the environment. Because of the large amount of data available to support model evaluation, production systems of the U.S. Meat Animal Research Center were simulated with the Integrated Farm System Model for the purpose of evaluating the environmental impact of the beef cattle produced. Presented by: Al Rotz

1. Environmental Footprints of
Beef Produced at MARC
USDA, Agricultural Research Service
University Park, Pennsylvania
C. A. Rotz, B. J. Isenberg,
K. R. Stackhouse-Lawson,
and E. J. Pollak

2.  A number of studies have evaluated the carbon
footprint of beef production
 Very few studies have looked
at other environmental issues
 There is a need for a more
holistic evaluation
 A methodology that can be
applied to all beef production systems

3. To develop a methodology for evaluating the
environmental footprints of current and historical
beef cattle production systems for the U.S. Meat
Animal Research Center (MARC)

4.  Life Cycle Assessment: an environmental
accounting program
 Process-based model: a simulation of the
production system
 Combined simulation and LCA:
Simulation is used to provide the
parameters for the LCA

5. Integrated Farm System Model

6. Feed Production
Animal Production
Manure Handling
Resource inputs
Fuel
Electricity
Fertilizer
Pesticide
Plastic
Machinery
Off-farm heifers
Purchased feed
Imported manure
Milk sold
Animals sold
Feed sold
Exported manure
Direct Sinks and Sources
Fixed CO2 CO2 N2O CH4 CO2 CH4 CO2 N2O
Farm
Pre-chain Sources
CO2 CH4 N2O
Emissions
allocated to
other farm
products
(Cradle-to-farm gate)

7.  Carbon emission
 Energy use
 Water use
 Reactive nitrogen loss

8.  Total CH4, N2O and CO2 emitted
expressed per unit of body
weight
 Excludes all biological sinks
and sources of CO2
 Includes the CO2 from combustion and
that assimilated in the CH4 produced

9.  Fossil energy used per unit body weight
produced
 Includes fuel, natural gas and
electricity use
 Includes energy used to produce the
resources used (fuel, electricity, fertilizer,
purchased feed, etc.)

10.  Water used per unit of body weight
produced
 Excludes precipitation
 Includes water used to produce
purchased feed

11.  Total reactive N lost per
unit of body weight
produced
 Includes:
Ammonia emission
Nitrous oxide emission
NOx emission
Nitrate leaching and runoff

12.  Farm
 Spring cow calf
 Fall cow calf
 Feedlot

13.  About 5,000 acres of alfalfa and corn with a few
acres of soybeans
 Alfalfa primarily harvested in large round bales
stored outside
 Corn harvested as silage, high moisture grain and
dry grain
 Irrigation is used to produce all crops
 Strip tillage system used for corn and soybeans

14.  (Spring calving) 4,100 cows plus replacements
(Fall calving) 1,400 cows plus replacements
 24,000 acres of grazed pasture
 Some pasture is irrigated (15 center pivots)
 Fed hay and silage during
the winter months

15.  About 3,700 cattle finished each year
 Backgrounded for 3 months on high forage (hay,
silage and distiller’s grain diet)
 Finished for 7 months on high grain (corn silage,
corn and distiller’s grain)
 Finished at 16 months of age with
an average weight of 1,280 lb
 All manure is returned to cropland

16.  Feed production
and use
 Energy use
 Production costs
Year 2011

17. Actual Simulated Difference
Ton DM Ton DM %
Alfalfa/grass hay & silage 9,506 9,596 0.9
Corn silage 8,400 8,409 0.0
High moisture corn 2,989 2,993 0.0
Corn grain 4,100 4,131 0.7
Soybeans 278 275 1.0
Total 25,273 25,404 0.5

18. Actual Simulated Difference
Ton DM Ton DM %
Pasture --- 25,430 ---
Alfalfa/grass hay & silage 6,096 6,102 0.0
Corn silage 5,444 5,422 0.4
High moisture corn 3,092 3,109 0.5
Corn grain 1,834 1,820 0.8
Distiller’s grain 1,841 1,837 0.2
Total 18,307 18,290 0.0

19. Actual Simulated Difference
Diesel fuel & gasoline Gallon 122,298 121,191 0.9 %
Natural gas Therm 103,656 103,952 0.3 %
Electricity kWh 1,070,441 1,070,880 0.0 %

20. Actual Simulated Difference
$ $ %
Seed and herbicide 285,300 285,344 0.0
Fertilizer 483,700 485,983 0.5
Energy 513,182 512,561 0.0
Labor 2,220,000 2,218,851 0.1
Purchased feed 566,000 564,328 0.3
Vet and medicine 80,000 80,496 0.6
Implant and ionophore 7,600 7,671 0.9
Breeding 60,000 60,028 0.9
Other miscellaneous 100,000 99,921 0.1

21.  Carbon footprint
 Energy footprint
 Water footprint
 Reactive nitrogen footprint

22. 56%27%
6% 11%
10.9 lb CO2e/lb body weight
CH4
N2O
Combustion
Pre-chain

23. Crop Farm
10%
Cow Calf
71%
Feedlot
19%
Individual Operation Contributions

24. 36%
9%
1%
1%
53%
11,400 Btu/lb body weight
Feed production
Animal feeding
Manure handling
Facilities
Pre-chain

25. Crop Farm
45%
Cow Calf
38%
Feedlot
17%
Individual Operation Contributions

26. 81%
1% 18%
335 gal/lb of body weight
Feed
production, irrigation
Drinking
Pre-chain

27. Crop Farm
61%
Cow Calf
26%
Feedlot
13%
Individual Operation Contributions

28. 81%
6%
9%
1% 3%
0.0914 lb N/lb body weight
Ammonia emission
Nitrate leaching
N2O
Combustion
Pre-chain

29. Crop Farm
6%
Cow Calf
61%
Feedlot
33%
Individual Operation Contributions

30.  Removed soybeans (replaced with corn)
 Reduced corn yield 6% (genetic gain)
 Reduced finish weight of cattle by 3%
 Increased animal numbers 3%
 Replaced distiller’s grain with
corn and a little urea

31.  Replaced 1,700 acres of corn with bromegrass
hay
 Reduced alfalfa yield 12%, corn yield 40%
 Removed irrigation of pasture
 Used smaller equipment and more tillage
 Reduced finish weight by 19%
 Increased animal numbers 19%
 Finished on corn silage and corn grain diet
 Finished at 16 months of age

32. 0
2
4
6
8
10
12
1970 2005 2011
Feedlot
Cow calf
Crop farm
lb CO2e/lb BW

33. 0
2
4
6
8
10
12
1970 2005 2011
Feedlot
Cow calf
Crop farm
MBtu/lb BW

34. 0
50
100
150
200
250
300
350
1970 2005 2011
Feedlot
Cow calf
Crop farm
Gallon/lb BW

35. 0
1
2
3
4
5
6
7
8
9
10
1970 2005 2011
Feedlot
Cow calf
Crop farm
lb N/cwt BW

36.  Our simulation methodology was able to accurately
represent feed production and use, energy use and
production costs of MARC
 Based upon simulated performance, environmental
footprints were determined
 Since 2005, feeding distiller’s grain has caused some increase
in the environmental footprints
 Since 1970, the carbon footprint has decreased 6% with no
change in the energy footprint, a 3% reduction in the reactive
nitrogen footprint, a 42% increase in the water footprint, and
a 6% reduction in the real cost of production

37. This proven methodology provides a means for further
analysis of regional and national impacts of beef
production and the production data needed for a full
life cycle assessment of the sustainability of beef

38.  Resource consumption
 Total air emissions
 Total water emissions
 Toxicity potential
 Solid waste
 Land use
 Social impacts
 Indicator of total impact

39. USDA
Pasture Systems and Watershed
Management Research Unit
University Park, Pennsylvania
Agricultural Research Service