1. New user-friendly phosphorus-loss model for cattle barnyards and feedlots helps reduce pollution abatement costs. Phosphorus loss in runoff from beef and dairy farms can pollute local lakes and streams, and barnyards and feedlots can be very high sources of phosphorus. An ARS scientist in Madison, Wisconsin developed and tested a user-friendly computer model that can quickly quantify how much phosphorus is lost from barnyards or feedlots each year. The model is being adapted by the Wisconsin Department of Natural Resources (DNR) for use in local adaptive management programs. These programs build partnerships between point source facilities and other landowners, municipalities, and private and public entities to reduce phosphorus pollution in compliance with local policies. The Madison Metropolitan Sewerage District estimates adaptive management can save them $185,000 per year to reduce their phosphorus pollution. The Wisconsin DNR estimates reducing phosphorus pollution could save the state $18.8 million over 20 years.
2. Phosphorus loss in runoff from cattle lots quantified; loss is small compared to field losses. Phosphorus loss in runoff from dairy farms can pollute local waters, but there is little information on how much loss comes from outdoor areas where cattle congregate and manure is not immediately collected. These outdoor cattle lots can range from densely stocked hard-surface barnyards to vegetated exercise lots with low stocking rates. ARS scientists in Madison, Wisconsin monitored phosphorus runoff for three years from the full range of dairy cattle lots. Annual phosphorus loss was a direct function of cattle stocking density in lots; phosphorus loss from densely stocked lots was 6 to 19 times greater than from low intensity, vegetated lots. Per unit land area, densely stocked lots can have the greatest rates of phosphorus loss from a dairy farm, including cropland. However, even though densely stocked cattle lots may be “hot spots” of phosphorus loss, and all types of outdoor cattle lots represent about 15% of the total land area on a farm, outdoor cattle lots contribute only 5% of total annual phosphorus loss on an average farm with the remainder coming from field runoff. Thus, targeting only cattle lots for phosphorus loss remediation may not dramatically reduce whole farm loss. Targeting cropland for phosphorus loss remediation, and subsequently maintaining or improving water quality, remains a priority.Good, L.W., Vadas, P.A., Panuska, J.C., Bonilla, C.A., Jokela, W.E. 2012. Testing the Wisconsin P index with year-round, field-scale runoff monitoring. Journal of Environmental Quality. 41:1730-1740.
Vadas, P.A., Joern, B.C., Moore Jr, P.A. 2012. Simulating soil phosphorus dynamics for a phosphorus loss quantification tool. Journal of Environmental Quality. 41:1750-1757.
Coblentz, W.K., Grabber, J.H. 2013. In situ protein degradation of alfalfa and birdsfoot trefoil hays and silages as influenced by condensed tannin concentration. Journal of Dairy Science. 96:3120-3137.
Coblentz, W.K., Muck, R.E. 2012. Effects of natural and simulated rainfall on indicators of ensilability and nutritive value for wilting alfalfa forages sampled before preservation as silage. Journal of Dairy Science. 95:6635-6653.
Coblentz, W.K., Hoffman, P.C., Esser, N.M., Bertram, M.G. 2012. Using eastern gamagrass to construct diets that limit intake and caloric density for dairy replacement heifers. Journal of Dairy Science. 95:6057-6071.
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Coffey, K.P., Montgomery, T., Coblentz, W.K., Francis, P.B., Whitworth, W.A., Bryant, K.J. 2013. Performance by heifers grazing sod-seeded cool-season annuals seeded on different dates using two tillage intensities. Forage and Grazinglands. DOI: 10.1094/FG-2013-0226-01-RS.
Coblentz, W.K., Coffey, K.P., Young, A.N., Bertram, M.G. 2013. Storage characteristics, nutritive value, energy content, and in-vivo digestibility of moist large-rectangular bales of alfalfa-orchardgrass hay treated with a propionic-acid-based preservative. Journal of Dairy Science. 96:2521-2535.
Gibson, K.E., Borchardt, M.A. 2013. Basic QA/QC information required for reporting real-time quantitative PCR data for drinking water quality. Journal of American Water Works Association. 105 (1): 45-47.
Lopes, F., Coblentz, W.K., Hoffman, P.C., Combs, D.K. 2013. Assessment of heifer grazing experience on short-term adaptation to pasture and performance as lactating cows. Journal of Dairy Science. 96:3138-3152.
Curran, R., Weigel, K., Hoffman, P.C., Marshall, J., Kuzdas, K., Coblentz, W.K. 2013. Relationships between age at first calving, herd management criteria and lifetime milk, fat, and protein production in holstein cattle. Professional Animal Scientist. 29:1-9.
Vadas, P.A., Digman, M.F. 2013. Production costs of potential corn stover harvest and storage systems. Biomass and Bioenergy. 54:133-139.
Mays, A.R., Looper, M.L., Williamson, B.C., Coffey, K.P., Coblentz, W.K., Aiken, G.E., Rosenkrans, C.F. 2013. Forage and breed effects on behavior and temperament of pregnant beef heifers. Journal of Animal Science and Biotechnology. 4:20. DOI:10.1186/2049-1891-4-20.
Bolster, C.H., Vadas, P.A., Sharpley, A.N., Lory, J.A. 2012. Using a phosphorus loss model to evaluate and improve phosphorus indices. Journal of Environmental Quality. 41(6):1758-1766.
Jokela, W.E., Coblentz, W.K., Hoffman, P.C. 2012. Dairy heifer manure management, dietary phosphorus, and soil test P effects on runoff phosphorus. Journal of Environmental Quality. 2012 41:(5): 1600-1611. DOI:10.2134/jeq2012.0046.
Sharpley, A., Beegle, D., Bolster, C., Good, L., Joern, B., Ketterings, Q., Lory, J., Mikkelsen, R., Osmond, D., Vadas, P. 2012. Phosphorus indices: why we need to take stock of how we are doing. Journal of Environmental Quality. 41(6):1711-1719.
Duval, B.D., Dijkstra, P., Megonigal, P.J., Ketterer, M.E., Drake, B.G., Johnson, D.W., Hungate, B.A. 2013. Element pool changes within a scrub-oak ecosystem after 11 years of elevated CO2 exposure. PLoS One. DOI:10.1371.