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| Projected Phosphorus (as K2O) Removal, "wet" or "as is" Basis |
% Moisture, Dry Matter | Number of Samples in Survey |
||||||||||
| Median | Survey Range | |||||||||||
| Pounds of K2O per yield unit | Survey range | Moisture | Dry Matter | |||||||||
¶ Grains, Oilseeds, Fiber, Sugar Crops |
||||||||||||
| Barley, grain | 0.24 | / bu (48 lb) | 1 | 0.21 | – | 0.27 | 11.1 | 88.9 | 87.2 | – | 90.0 | 162 |
| Beans (dry) | 0.92 | / cwt (100 lb) | 2 | 10.0 | 90.0 | --- | ||||||
| Beans (navy) | 1.49 | / cwt (100 lb) | 3 | 10.0 | 90.0 | --- | ||||||
| Buckwheat, grain | 0.27 | / bu (52 lb) | 2 | 12.0 | 88.0 | --- | ||||||
| Canola, grain | 0.40 | / bu (60 lb) | 4 | 8.0 | 92.0 | --- | ||||||
| Corn, grain (dry shelled) | 0.19 | / bu (56 lb) | 1 | 0.18 | – | 0.20 | 14.2 | 85.9 | 84.9 | – | 86.7 | 2,676 |
| 0.34 | / cwt (100 lb) | 1 | 0.32 | – | 0.36 | 14.2 | 85.9 | 84.9 | – | 86.7 | 2,676 | |
| Corn, grain (high moisture) | 0.15 | / bu (56 lb) | 1 | 0.14 | – | 0.16 | 29.7 | 70.3 | 67.4 | – | 72.9 | 2,897 |
| 0.27 | / cwt (100 lb) | 1 | 0.25 | – | 0.29 | 29.7 | 70.3 | 67.4 | – | 72.9 | 2,897 | |
| Cotton (seed, lint, trash) (≈1300 lb seed cotton yields 480 lb lint) |
10.2 | / 1300 lb (bale) | 6 | --- | --- | --- | ||||||
| Cotton seeds | 1.06 | / cwt (100 lb) | 4 | 8.0 | 92.0 | --- | ||||||
| Field pea, seeds | 0.68 | / bu (60 lb) | 4 | 11.5 | 88.5 | --- | ||||||
| Flax, grain | 0.60 | / bu (56 lb) | 2 | 8.7 | 91.3 | --- | ||||||
| Millet grain | 0.25 | / bu (50 lb) | 4 | 13.0 | 87.0 | --- | ||||||
| Oats, grain | 0.15 | / bu (32 lb) | 1 | 0.13 | – | 0.18 | 11.0 | 89.0 | 87.8 | – | 90.6 | 67 |
| Peanuts, whole | 0.88 | / cwt (100 lb) | 6 | 10.0 | 90.0 | --- | ||||||
| Potato tuber, fresh | 0.55 | / cwt (100 lb) | 4 | 77.0 | 23.0 | --- | ||||||
| Rice, grain | 0.19 | / bu (45 lb) | 4 | 11.0 | 89.0 | --- | ||||||
| Rye, grain | 0.29 | / bu (56 lb) | 1 | 11.0 | 89.0 | --- | ||||||
| Safflower seeds | 0.28 | / bu (38 lb) | 7 | 8.0 | 92.0 | --- | ||||||
| Sorghum, grain (milo) | 0.20 | / bu (56 lb) | 1 | 0.19 | – | 0.21 | 13.0 | 87.0 | 85.8 | – | 88.2 | 481 |
| 0.36 | / cwt (100 lb) | 1 | 0.34 | – | 0.38 | 13.0 | 87.0 | 85.8 | – | 88.2 | 481 | |
| Soybeans, whole | 1.16 | / bu (60 lb) | 4 | 12.0 | 88.0 | --- | ||||||
| Spelt, grain | 0.16 | / bu (40 lb) | 4 | 12.0 | 88.0 | --- | ||||||
| Sugarbeet (root) | 7.30 | / ton | 2 | 80.0 | 20.0 | --- | ||||||
| Sugarcane | 3.50 | / ton | 2 | 74.0 | 26.0 | --- | ||||||
| Sunflower seeds | 0.90 | / cwt (100 lb) | 2 | 9.8 | 90.3 | --- | ||||||
| Triticale, grain | 0.31 | / bu (60 lb) | 4 | 11.0 | 89.0 | --- | ||||||
| Wheat, grain | 0.26 | / bu (60 lb) | 1 | 0.23 | – | 0.28 | 11.3 | 88.7 | 87.5 | – | 89.9 | 244 |
| "Potassium" is expressed in terms of fertilizer equivalent potash as "K2O", where K x 1.16 = K2O. | ||||||||||||
| To estimate the equivalent hay or silage yield based on grain yield or to estimate stocking rates (as animal units) based on equivalent hay yield, see Crop File 1.02.022, "Yield Goal Equivalents: Silage, Hay, and Pasture." | ||||||||||||
| Projected Phosphorus (as K2O) Removal, "wet" or "as is" Basis |
% Moisture, Dry Matter | Number of Samples in Survey |
||||||||||
| Median | Survey Range | |||||||||||
| Pounds of K2O per Yield Unit | Survey range | Moisture | Dry Matter | |||||||||
¶ Hay, Legumes |
||||||||||||
| Alfalfa hay | 49.4 | / ton | 1 | 42.5 | – | 56.7 | 12.7 | 87.3 | 85.0 | – | 89.1 | 7,463 |
| Clover, hay alsike clover | 47.5 | / ton | 2 | 12.6 | 87.4 | --- | ||||||
| Clover hay, ladino clover | 50.1 | / ton | 4 | 10.0 | 90.0 | --- | ||||||
| Clover hay, red clover | 34.7 | / ton | 4 | 12.0 | 88.0 | --- | ||||||
| Clover hay, sweetclover | 38.0 | / ton | 4 | 9.0 | 91.0 | --- | ||||||
| Cowpea hay | 40.0 | / ton | 6 | 9.6 | 90.4 | --- | ||||||
| Lespedeza hay | 21.3 | / ton | 6 | 8.0 | 92.0 | --- | ||||||
| Peanut hay | 48.7 | / ton | 6 | 10.8 | 89.2 | --- | ||||||
| Soybean hay | 31.5 | / ton | 1 | 25.1 | – | 36.4 | 13.0 | 87.1 | 83.2 | – | 90.4 | 52 |
| Trefoil hay, birdsfoot trefoil | 37.2 | / ton | 4 | 11.0 | 89.0 | --- | ||||||
| Vetch hay | 49.6 | / ton | 4 | 11.0 | 89.0 | --- | ||||||
¶ Hay, Grasses |
||||||||||||
| Bahiagrass | 29.2 | / ton | 4 | 10.0 | 90.0 | --- | ||||||
| Bermudagrass hay | 38.1 | / ton | 1 | 31.5 | – | 46.6 | 10.0 | 90.0 | 87.4 | – | 91.8 | 232 |
| Bluegrass hay | 39.7 | / ton | 3 | 11.0 | 89.1 | --- | ||||||
| Bluestem hay | 10.4 | / ton | 3 | 9.9 | 90.1 | --- | ||||||
| Bromegrass hay | 39.2 | / ton | 4 | 11.8 | 88.2 | --- | ||||||
| Fescue hay | 34.7 | / ton | 4 | 12.2 | 87.8 | --- | ||||||
| Meadow hay | 38.4 | / ton | 1 | 31.7 | – | 43.3 | 10.6 | 89.4 | 87.0 | – | 90.9 | 193 |
| Mixed grass hay | 32.6 | / ton | 1 | 23.2 | – | 41.6 | 10.7 | 89.3 | 86.5 | – | 91.8 | 2,358 |
| Native grass hay | 14.4 | / ton | 1 | 7.4 | – | 25.6 | 12.9 | 87.1 | 67.5 | – | 90.5 | 192 |
| Orchardgrass hay | 53.1 | / ton | 4 | 12.0 | 88.0 | --- | ||||||
| Prairie hay | 22.4 | / ton | 1 | 17.7 | – | 30.6 | 11.4 | 88.6 | 86.6 | – | 90.2 | 200 |
| Reed canarygrass hay | 57.0 | / ton | 4 | 9.0 | 91.0 | --- | ||||||
| Ryegrass hay | 45.9 | / ton | 4 | 8.5 | 91.5 | --- | ||||||
| Switchgrass hay | 39.3 | / ton | 3 | 4.6 | 95.4 | --- | ||||||
| Timothy hay | 36.7 | / ton | 4 | 12.0 | 88.0 | --- | ||||||
| Wheatgrass hay | 42.7 | / ton | 4 | 11.7 | 88.4 | --- | ||||||
| "Potassium" is expressed in terms of fertilizer equivalent potash as "K2O", where K x 1.16 = K2O. | ||||||||||||
| To estimate the equivalent hay or silage yield based on grain yield or to estimate stocking rates (as animal units) based on equivalent hay yield, see Crop File 1.02.022, "Yield Goal Equivalents: Silage, Hay, and Pasture." | ||||||||||||
| Projected Phosphorus (as K2O) Removal, "wet" or "as is" Basis |
% Moisture, Dry Matter | Number of Samples in Survey |
||||||||||
| Median | Survey Range | |||||||||||
| Pounds of K2O per Yield Unit | Survey Range | Moisture | Dry Matter | |||||||||
¶ Hay, Small Grains |
||||||||||||
| Barley hay | 35.6 | / ton | 1 | 29.2 | – | 43.7 | 13.2 | 86.8 | 84.1 | – | 88.7 | 713 |
| Millet hay | 53.9 | / ton | 1 | 42.6 | – | 62.8 | 13.1 | 86.9 | 83.3 | – | 89.4 | 238 |
| Oat hay | 46.7 | / ton | 1 | 39.8 | – | 54.7 | 12.1 | 87.9 | 84.9 | – | 90.1 | 625 |
| Rye hay | 26.6 | / ton | 3 | 12.4 | 87.6 | --- | ||||||
| Triticale hay | 40.7 | / ton | 1 | 31.6 | – | 52.1 | 10.4 | 89.6 | 86.0 | – | 92.0 | 146 |
| Wheat hay | 34.9 | / ton | 1 | 26.3 | – | 46.0 | 11.5 | 88.5 | 84.9 | – | 90.7 | 534 |
¶ Hay, annual sorghums |
||||||||||||
| Haygrazer hay | 37.9 | / ton | 31.7 | – | 48.1 | 17.2 | 82.8 | 54.6 | – | 88.9 | 66 | |
| Sorghum hay | 42.3 | / ton | 1 | 32.5 | – | 55.4 | 17.1 | 82.9 | 74.7 | – | 87.5 | 153 |
| Sorghum-sudan hay | 45.6 | / ton | 1 | 36.9 | – | 55.4 | 16.3 | 83.7 | 74.7 | – | 88.0 | 106 |
| Sudan hay | 41.6 | / ton | 1 | 33.5 | – | 51.9 | 16.2 | 83.8 | 77.3 | – | 87.8 | 183 |
¶ Hay, Miscellaneous |
||||||||||||
| Cane hay | 41.1 | / ton | 1 | 32.1 | – | 50.8 | 17.0 | 83.0 | 77.4 | – | 86.8 | 218 |
| Corn hay | 31.0 | / ton | 1 | 22.9 | – | 38.5 | 14.3 | 85.7 | 77.9 | – | 89.7 | 58 |
¶ Silage, Annual Crops |
||||||||||||
| Barley silage | 13.8 | / ton | 1 | 12.0 | – | 16.8 | 66.3 | 33.7 | 30.8 | – | 38.3 | 371 |
| Cane silage | 12.0 | / ton | 1 | 10.0 | – | 14.5 | 71.4 | 28.6 | 24.9 | – | 33.3 | 154 |
| Corn silage | 9.5 | / ton | 1 | 8.1 | – | 11.2 | 66.3 | 33.7 | 30.2 | – | 37.8 | 7,798 |
| Milo silage (grain sorghum) | 12.4 | / ton | 1 | 10.0 | – | 14.9 | 64.9 | 35.1 | 28.9 | – | 41.4 | 84 |
| Oat silage | 18.0 | / ton | 1 | 15.3 | – | 20.9 | 64.8 | 35.3 | 29.1 | – | 42.8 | 84 |
| Oatlage | 17.8 | / ton | 1 | 15.2 | – | 22.3 | 66.3 | 33.7 | 28.9 | – | 43.0 | 120 |
| Rye silage | 18.5 | / ton | 1 | 14.5 | – | 22.4 | 68.9 | 31.1 | 26.0 | – | 38.6 | 161 |
| Small grain silage | 18.9 | / ton | 1 | 16.7 | – | 22.6 | 65.1 | 34.9 | 30.7 | – | 38.7 | 592 |
| Sorghum silage | 12.5 | / ton | 1 | 10.6 | – | 14.9 | 70.5 | 29.5 | 26.2 | – | 33.1 | 1,295 |
| Sorghum-sudan silage | 13.9 | / ton | 1 | 68.5 | 31.5 | --- | ||||||
| Sudangrass silage | 17.1 | / ton | 1 | 14.6 | – | 21.2 | 71.0 | 29.1 | 24.5 | – | 36.3 | 56 |
| Triticale silage | 20.9 | / ton | 1 | 16.8 | – | 25.4 | 67.3 | 32.7 | 28.1 | – | 38.8 | 297 |
| Wheatlage | 21.6 | / ton | 1 | 17.8 | – | 27.2 | 63.9 | 36.1 | 31.5 | – | 41.7 | 784 |
| Wheat silage | 18.4 | / ton | 1 | 14.7 | – | 21.8 | 65.5 | 34.5 | 30.3 | – | 39.9 | 370 |
¶ Silage, Perennial Crops |
||||||||||||
| Alfalfa haylage | 27.2 | / ton | 1 | 23.8 | – | 30.7 | 59.1 | 40.9 | 34.1 | – | 48.1 | 668 |
| Alfalfa silage | 18.9 | / ton | 1 | 16.6 | – | 22.8 | 64.0 | 36.0 | 31.3 | – | 43.2 | 154 |
| Bermudagrass silage | 9.0 | / ton | 4 | 74.0 | 26.0 | --- | ||||||
| Bromegrass silage | 16.2 | / ton | 4 | 65.0 | 35.0 | --- | ||||||
| Mixed grass silage | 14.6 | / ton | 4 | 70.0 | 30.0 | --- | ||||||
| Ryegrass silage | 21.5 | / ton | 4 | 68.0 | 32.0 | --- | ||||||
| Timothy silage | 13.4 | / ton | 4 | 66.0 | 34.0 | --- | ||||||
| "Phosphorus" is expressed in terms of fertilizer equivalent phosphate as "P2O5", where P x 2.28 = P2O5. | ||||||||||||
| To estimate the equivalent hay or silage yield based on grain yield or to estimate stocking rates (as animal units) based on equivalent hay yield, see Crop File 1.02.022, "Yield Goal Equivalents: Silage, Hay, and Pasture." | ||||||||||||
| Projected Phosphorus (as K2O) removal, "wet" or "as is" basis |
% Moisture, Dry Matter | Number of Samples in Survey |
||||||||||
| Median | Survey Range | |||||||||||
| Pounds of K2O per Yield Unit | Survey Range | Moisture | Dry Matter | |||||||||
¶ Crop Residues |
||||||||||||
| Barley straw | 45.9 | / ton | 4 | 10.0 | 90.0 | --- | ||||||
| (72 lb straw/bu) | 1.65 | / bu harvested | --- | --- | --- | |||||||
| Buckwheat straw | 53.9 | / ton | 3 | 11.3 | 88.7 | --- | ||||||
| Corn cobs | 16.7 | / ton | 4 | 6.4 | 93.6 | --- | ||||||
| Corn stalks | 24.5 | / ton | 1 | 15.0 | 85.0 | 79.9 | – | 88.1 | 502 | |||
| Corn stover | 21.4 | / ton | 1 | 11.3 | 88.7 | 83.3 | – | 92.1 | 71 | |||
| (70 lb stover/bu) | 0.75 | / bu harvested | --- | --- | --- | |||||||
| Cotton stover | ||||||||||||
| (1300 lb seed cotton yields 480 lb lint) | 6.80 | / bale | 5 | 7.7 | 92.3 | --- | ||||||
| Flax straw (80 lb straw/bu) | 1.50 | / bu harvested | 3 | 7.7 | 93.0 | --- | ||||||
| Millet straw | 39.0 | / ton | 2 | 10.0 | 90.0 | --- | ||||||
| (84 lb straw/bu) | 1.64 | / bu harvested | --- | --- | --- | |||||||
| Oat straw | 50.1 | / ton | 3 | 9.0 | 90.3 | --- | ||||||
| (44 lb straw/bu) | 1.10 | / bu harvested | --- | --- | --- | |||||||
| Peanut stover | 24.0 | / ton | 2 | --- | --- | --- | ||||||
| Popcorn stover | 17.3 | / ton | 3 | 12.7 | 87.3 | --- | ||||||
| (56 lb stover/bu) | 0.48 | / bu harvested | --- | --- | --- | |||||||
| Potato vines | 13.9 | / ton | 4 | 85.0 | 15.0 | --- | ||||||
| Rice straw | 25.3 | / ton | 4 | 9.2 | 90.8 | --- | ||||||
| (100 lb straw/cwt) | 1.27 | / cwt harvested | --- | --- | --- | |||||||
| Rye straw | 20.6 | / ton | 4 | 9.1 | 90.9 | --- | ||||||
| (87 lb straw/bu) | 0.90 | / bu harvested | --- | --- | --- | |||||||
| Sorghum stover | 24.2 | / ton | 4 | 8.1 | 91.9 | --- | ||||||
| (56 lb stover/bu) | 0.68 | / bu harvested | --- | --- | --- | |||||||
| Soybean stover | 12.2 | / ton | 4 | 13.9 | 86.2 | --- | ||||||
| (96 lb stover/bu) | 0.59 | / bu harvested | --- | --- | --- | |||||||
| Sugarbeet top | 22.9 | / ton | 4 | 81.0 | 19.0 | --- | ||||||
| Sunflower stover | 34.0 | / ton | 2 | 13.3 | 86.7 | --- | ||||||
| (150 lb stover/cwt) | 2.55 | / cwt harvested | --- | --- | --- | |||||||
| Wheat straw | 26.0 | / ton | 1 | 18.8 | – | 37.5 | 9.8 | 90.3 | 86.5 | – | 94.0 | 156 |
| (92 lb straw/bu) | 1.19 | / bu harvested | --- | --- | ||||||||
| "Phosphorus" is expressed in terms of fertilizer equivalent phosphate as "P2O5", where P x 2.28 = P2O5. | ||||||||||||
| To estimate the equivalent hay or silage yield based on grain yield or to estimate stocking rates (as animal units) based on equivalent hay yield, see Crop File 1.02.022, "Yield Goal Equivalents: Silage, Hay, and Pasture." | ||||||||||||
| Projected Phosphorus (as K2O) Removal, "wet" or "as is" Basis |
% Moisture, Dry Matter | Number of Samples in Survey |
||||||||||
| Median | Survey Range | |||||||||||
| Pounds of K2O per Yield Unit | Survey Range | Moisture | Dry Matter | |||||||||
¶ Fresh Forage, Vegetative Stage - Annuals |
||||||||||||
| Corn plants, fresh | 13.7 | / ton | 1 | 12.2 | – | 16.5 | 74.0 | 26.1 | 21.3 | – | 33.8 | 77 |
| Forage sorghum plants, fresh | 12.9 | / ton | 3 | 71.5 | 28.5 | --- | ||||||
| Millet plants, fresh | 12.4 | / ton | 3 | 70.0 | 30.1 | --- | ||||||
| Milo plants, fresh (grain sorghum) | 13.5 | / ton | 3 | 66.6 | 33.4 | --- | ||||||
| Oat plants, fresh | 11.4 | / ton | 3 | 70.4 | 29.6 | --- | ||||||
| Rye plants, fresh | 14.8 | / ton | 3 | 68.9 | 31.2 | --- | ||||||
| Sorghum plants, fresh | 13.5 | / ton | 3 | 71.9 | 28.1 | --- | ||||||
| Sorghum-sudan plants, fresh | 12.9 | / ton | 3 | 72.4 | 27.6 | --- | ||||||
| Sudangrass plants, fresh | 9.2 | / ton | 75.1 | 24.9 | --- | |||||||
| Triticale plants, fresh | 14.8 | / ton | 68.0 | 32.0 | --- | |||||||
| Wheat plants, fresh | 17.1 | / ton | 1 | 14.0 | – | 24.4 | 63.2 | 36.9 | 27.5 | – | 47.3 | 87 |
¶ Fresh Forage, Vegetative Stage - Perennial Grasses |
||||||||||||
| Bermudagrass, fresh | 13.2 | / ton | 3 | 71.0 | 29.0 | --- | ||||||
| Bluestem, fresh | 11.3 | / ton | 4 | 39.0 | 61.0 | --- | ||||||
| Bromegrass, fresh | 16.0 | / ton | 4 | 70.0 | 30.0 | --- | ||||||
| Fescue, fresh | 16.8 | / ton | 4 | 71.0 | 29.0 | --- | ||||||
| Mixed grass, fresh | 13.8 | / ton | 1 | 4.5 | – | 19.0 | 30.5 | 69.6 | 46.2 | – | 86.9 | 2,829 |
| Native grass, fresh | 13.6 | / ton | 1 | 9.5 | – | 17.7 | 58.5 | 41.6 | 33.5 | – | 52.1 | 136 |
| Orchardgrass, fresh | 15.0 | / ton | 4 | 76.0 | 24.0 | --- | ||||||
| Timothy, fresh | 11.5 | / ton | 4 | 74.0 | 26.0 | --- | ||||||
| Wheatgrass (crested), fresh | 20.6 | / ton | 4 | 63.0 | 37.0 | --- | ||||||
¶ Fresh Forage, Vegetative Stage - Legumes |
||||||||||||
| Alfalfa, fresh | 19.3 | / ton | 1 | 16.2 | – | 21.1 | 72.4 | 27.6 | 20.8 | – | 39.5 | 62 |
| Clover (ladino), fresh | 10.6 | / ton | 4 | 81.0 | 19.0 | --- | ||||||
| Clover (red), fresh | 11.1 | / ton | 4 | 76.0 | 24.0 | --- | ||||||
| Lespedeza, fresh | 6.4 | / ton | 4 | 75.0 | 25.0 | --- | ||||||
| Trefoil (birdsfoot) fresh | 13.3 | / ton | 4 | 78.0 | 22.0 | --- | ||||||
| "Phosphorus" is expressed in terms of fertilizer equivalent phosphate as "P2O5", where P x 2.28 = P2O5. | ||||||||||||
| To estimate the equivalent hay or silage yield based on grain yield or to estimate stocking rates (as animal units) based on equivalent hay yield, see Crop File 1.02.022, "Yield Goal Equivalents: Silage, Hay, and Pasture." | ||||||||||||
The value provided as "pounds per yield unit" is either the median value from the Servi-Tech survey or the most common central value obtained from the references. The "survey range" represents either the 25th and 75th percentile from the Servi-Tech data or represents the low and high values from the referenced sources.
ServiTech Laboratories. 2014. In-house data survey of feed analysis results, 2006-2013. Results reported as "Median" or 50th percentile. "Typical range" includes the middle 50% of all samples, so 25% of samples are above range and 25% below. Statistical calculations based on listed number of samples of particular feedsuff that was included in data survey.
IPNI. IPNI Estimates of Nutrient Uptake and Removal. International Plant Food Institute, Peachtree Corners, GA (http://www.ipni.net/article/IPNI-3296, 25 June 2014)
USDA, NRCS. 2007. The PLANTS Database . National Plant Data Center, Baton Rouge, LA (http://plants.usda.gov, 25 June 2014)
BEEF. 2014 Feed Composition Table. BEEF magazine, Minneapolis MN (http://beefmagazine.com/datasheet/2014-feed-composition-table, 25 June 2014)
Stichler, C. and M. McFarland. 2001. Crop Nutrient Needs in South and Southwest Texas. Pub. No. B-6053. Texas Agric. Ext. Serv., College Station TX.
Osmond, D.L. and J. Kang. 2008. Nutrient Removal by Crops in North Carolina. Soil Facts #AG-439-16W. North Carolina State Univ., Coop. Ext. Serv., Raleigh NC.
eat THIS MUCH.com. 2014. Safflower seed kernels: seeds, dried. http://www.eatthismuch.com/food/view/safflower-seed-kernels,3297/
Albers, D.W., S. Hefner, and D. Klobe. 1993. Fertility Management of Cotton. Pub. G4256. Univ. of Missouri Extension, Columbia MO. (http://extension.missouri.edu/p/G4256, 25 June 2014)
Dahnke, W.C., L.J. Swenson, and A. Johnson. Crop Nutrient Removals vs. Fertilizer Additions in North Dakota. http://library.ndsu.edu/tools/dspace/load/?file=/repository/bitstream/handle/10365/8084/farm_44_01_03.pdf
Pettygrove, S. and I. Bay. 2009. Manure Technical Bulletin Series: Crop Nutrient Harvest Removal. Div. of Agric. and Nat.Res., Univ. of California, Davis CA (http://manuremanagement.ucdavis.edu/files/134365.pdf, 25 June 2014)
Rochester, J.J., G.A. Constable, D.M. Oosterhuis, and M. Errington 2012. "Nutritional Requirements of Cotton During Flowering and Fruiting" in Flowering and Fruiting in Cotton. The Cotton Foundation, Cordova TN. pg. 41. (www.cotton.org/foundation/upload/F-F-Chapter-4.pdf, 25 June 2014)
Walker, J. 2007. Oilseed Crops in Beef Cattle Rations. Extension Extra 2058. South Dakota State Univ. Coop. Ext. Serv., Brookings SD. (http://pubstorage.sdstate.edu/agbio_publications/articles/exex2058.pdf, 25 June 2014)