| Crop | seed / lb | seed / acre | lb seed / acre | kg seed / ha |
|---|---|---|---|---|
| Alfalfa | 227000 | 3405000 | 15 | 17 |
| Barley | 9400 | 921200 | 98 | 110 |
| Chickpeas (garbanzos) | NA | NA | 159 | 178 |
| Corn (grain) | 1361 | 40250 | 30 | 34 |
| Corn (silage) | 1361 | 40250 | 30 | 34 |
| Cotton | 4500 | 85000 | 19 | 21 |
| Dry Beans | 800 | 130680 | 163 | 183 |
| Dry Peas | 3200 | 139392 | 44 | 49 |
| Fava Beans | NA | NA | 163 | 183 |
| Lentils | 7467 | 522720 | 70 | 78 |
| Lupin | NA | NA | 163 | 183 |
| Peanuts | 460 | 105000 | 228 | 255 |
| Potatoes | 5 | 34848 | 6970 | 7806 |
| Rice | 15600 | 2438360 | 156 | 175 |
| Sorghum | 8333 | 100000 | 12 | 13 |
| Soybeans | 1500 | 250000 | 167 | 187 |
| Sugar beets | 22000 | 435600 | 20 | 22 |
| Wheat (durum) | 9550 | 1500000 | 157 | 176 |
| Wheat (spring) | 9550 | 1500000 | 157 | 176 |
| Wheat (winter) | 9550 | 1500000 | 157 | 176 |
Impact Factors of Seed Production
Methods 5.0
Seed impact factors were developed using the updated impact factors and methods for FP v5, and available crop production data from USDA NASS at the national level and the literature to fill data gaps. An assumption for transportation of seeds was obtained from BLS (2017) .
Details
Seeds are another agricultural input for which we need to estimate the associated energy use and GHG emissions for their manufacturing. Most seed production is conducted by the private industry, and, to our knowledge, no recent source of seed production data by crop exists.
To update the impact factors for seed production, we conducted an analysis with national level assumptions for the production of a crop, which required filling in the inputs listed in Foreground Activity Data. The Commodity Flow Survey from BLS (2017) provided an estimate of transportation miles, while USDA NASS surveys and the census of agriculture provided some of the crop production information. Other inputs were filled using data published in journal articles and enterprise crop budgets created by Universities.
Seeding Rates
Energy use factors
The energy use impact factors are described below.
- System Boundary: The impact factors in this section are attributed to the Upstream boundary.
- Source Category: It classifies the energy use to indicate it is associated with the production of seeds.
- Source Detail: A given crop seed option.
- MJ: Impact factor of megajoules per unit.
- Unit: Expected unit to use the MJ impact factor.
| System Boundary | Source Detail | MJ | Unit |
|---|---|---|---|
| Upstream | Seed | Alfalfa | 50.9 | kg seed |
| Upstream | Seed | Barley | 14.3 | kg seed |
| Upstream | Seed | Chickpeas (garbanzos) | 10.3 | kg seed |
| Upstream | Seed | Corn (grain) | 5.5 | kg seed |
| Upstream | Seed | Corn (silage) | 5.5 | kg seed |
| Upstream | Seed | Cotton | 38.2 | kg seed |
| Upstream | Seed | Dry Beans | 24.0 | kg seed |
| Upstream | Seed | Dry Peas | 15.6 | kg seed |
| Upstream | Seed | Fava Beans | 4.9 | kg seed |
| Upstream | Seed | Lentils | 9.9 | kg seed |
| Upstream | Seed | Lupin | 35.8 | kg seed |
| Upstream | Seed | Peanuts | 9.1 | kg seed |
| Upstream | Seed | Potatoes | 1.9 | kg seed |
| Upstream | Seed | Rice | 6.8 | kg seed |
| Upstream | Seed | Sorghum | 26.1 | kg seed |
| Upstream | Seed | Soybeans | 9.7 | kg seed |
| Upstream | Seed | Sugar beets | 33.8 | kg seed |
| Upstream | Seed | Wheat (durum) | 21.2 | kg seed |
| Upstream | Seed | Wheat (spring) | 21.2 | kg seed |
| Upstream | Seed | Wheat (winter) | 21.2 | kg seed |
| Upstream | Seed | Brassicas (interseeded) | 6.4 | kg seed |
| Upstream | Seed | Brassicas | 6.4 | kg seed |
| Upstream | Seed | Clovers (interseeded) | 9.4 | kg seed |
| Upstream | Seed | Clovers | 9.4 | kg seed |
| Upstream | Seed | Legumes | 9.4 | kg seed |
| Upstream | Seed | Spring cover crop mix (cool season) | 9.6 | kg seed |
| Upstream | Seed | Winter cover crop mix (cool season) | 9.6 | kg seed |
| Upstream | Seed | Cover crop mix (warm season) | 9.6 | kg seed |
| Upstream | Seed | Cover crop grass spring mix (cool season) | 21.2 | kg seed |
| Upstream | Seed | Cover crop grass winter mix (cool season) | 21.2 | kg seed |
GHG emission factors
The GHG emission impact factors are described below.
- System Boundary: The impact factors in this section are attributed to the Upstream boundary.
- Source Category: It classifies the GHG emissions to indicate they are associated with the production of seeds.
- Source Detail: A given crop seed option.
- CO2_fossil: Impact factor for fossil CO2 in kg of gas per unit.
- CH4_fossil: Impact factor of fossil CH4 in kg of gas per unit.
- N2O: Impact factor for N2O in kg of gas per unit.
- Unit: Expected unit to use the GHG emissions impact factor.
| System Boundary | Source Detail | CO2_fossil | CH4_fossil | CH4_biogenic | N2O | Unit |
|---|---|---|---|---|---|---|
| Upstream | Seed | Alfalfa | 1.19 | 0.0009350 | 0.0000000 | 0.0016185 | kg seed |
| Upstream | Seed | Barley | 0.37 | 0.0002320 | 0.0000000 | 0.0007994 | kg seed |
| Upstream | Seed | Chickpeas (garbanzos) | 0.36 | 0.0001741 | 0.0000000 | 0.0004478 | kg seed |
| Upstream | Seed | Corn (grain) | 0.18 | 0.0000937 | NA | 0.0007057 | kg seed |
| Upstream | Seed | Corn (silage) | 0.18 | 0.0000937 | NA | 0.0007057 | kg seed |
| Upstream | Seed | Cotton | 0.82 | 0.0008903 | 0.0000000 | 0.0004091 | kg seed |
| Upstream | Seed | Dry Beans | 0.64 | 0.0004066 | 0.0000000 | 0.0012020 | kg seed |
| Upstream | Seed | Dry Peas | 0.42 | 0.0002724 | 0.0000000 | 0.0003992 | kg seed |
| Upstream | Seed | Fava Beans | 0.14 | 0.0000862 | 0.0000000 | 0.0003249 | kg seed |
| Upstream | Seed | Lentils | 0.39 | 0.0001613 | 0.0000000 | 0.0004663 | kg seed |
| Upstream | Seed | Lupin | 0.97 | 0.0006442 | 0.0000000 | 0.0005247 | kg seed |
| Upstream | Seed | Peanuts | 0.27 | 0.0002048 | 0.0000000 | 0.0008203 | kg seed |
| Upstream | Seed | Potatoes | 0.06 | 0.0000260 | 0.0000000 | 0.0002237 | kg seed |
| Upstream | Seed | Rice | 0.18 | 0.0001281 | 0.0593471 | 0.0006080 | kg seed |
| Upstream | Seed | Sorghum | 0.63 | 0.0004784 | 0.0000000 | 0.0009477 | kg seed |
| Upstream | Seed | Soybeans | 0.34 | 0.0001977 | 0.0000000 | 0.0004425 | kg seed |
| Upstream | Seed | Sugar beets | 0.96 | 0.0005599 | 0.0000000 | 0.0035886 | kg seed |
| Upstream | Seed | Wheat (durum) | 0.56 | 0.0003599 | 0.0000000 | 0.0014283 | kg seed |
| Upstream | Seed | Wheat (spring) | 0.56 | 0.0003599 | 0.0000000 | 0.0014283 | kg seed |
| Upstream | Seed | Wheat (winter) | 0.56 | 0.0003599 | 0.0000000 | 0.0014283 | kg seed |
| Upstream | Seed | Brassicas (interseeded) | 0.19 | 0.0001140 | 0.0000000 | 0.0002820 | kg seed |
| Upstream | Seed | Brassicas | 0.19 | 0.0001140 | 0.0000000 | 0.0002820 | kg seed |
| Upstream | Seed | Clovers (interseeded) | 0.26 | 0.0001710 | 0.0000000 | 0.0003470 | kg seed |
| Upstream | Seed | Clovers | 0.26 | 0.0001710 | 0.0000000 | 0.0003470 | kg seed |
| Upstream | Seed | Legumes | 0.26 | 0.0001710 | 0.0000000 | 0.0003470 | kg seed |
| Upstream | Seed | Spring cover crop mix (cool season) | 0.26 | 0.0001720 | 0.0000000 | 0.0003840 | kg seed |
| Upstream | Seed | Winter cover crop mix (cool season) | 0.26 | 0.0001720 | 0.0000000 | 0.0003840 | kg seed |
| Upstream | Seed | Cover crop mix (warm season) | 0.26 | 0.0001720 | 0.0000000 | 0.0003840 | kg seed |
| Upstream | Seed | Cover crop grass spring mix (cool season) | 0.56 | 0.0003599 | 0.0000000 | 0.0014283 | kg seed |
| Upstream | Seed | Cover crop grass winter mix (cool season) | 0.56 | 0.0003599 | 0.0000000 | 0.0014283 | kg seed |
References
BLS. 2017. “Commodity Flow Survey (CFS).” https://www.bts.gov/cfs.