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Northeast Region Phosphorus Index

How to Find High Risk Fields and Beneficial Management Practices to Reduce P Loss Risk?

In 2022, the first Northeast Region Phosphorus Index was released for use in New York, Connecticut, New Hampshire, Maine, Massachussetts, and Rhode Island. This Phosphorus Index (PI) is a field management tool designed to estimate the relative risk of phosphorus (P) runoff from agricultural fields and incentivize implementation of beneficial management practices (BMPs) that can reduce the risk of P loss from fields. 

The development of the Northeast Region PI was made possible due to a multistate USDA-NRCS conservation innovation grant entitled "Revising and implementing phosphorus indices to protect water quality in the northeastern US (grant 69-3A75-17-26)". A new landscape x BMP approach was presented and released for use for nutrient management planning in New York in December of 2019 at the Northeast Region Certified Crop Advisor Training. Over the years that followed, adoption of a similar approach was discussed and evaluated across the New England states, to faciliate consistency on P risk assessment across state boundaries. These discussions and evaluations resulting in the release of the Northeast Region PI in 2022.

The Northeast Region PI does not estimate actual P loss, reflecting challenges with accurately predicting loss of P from individual fields. It rates fields for relative risk of particulate and dissolved P runoff and triggers management changes designed to reduce P runoff risk. This approach has been shown to drive management decisions toward practices that reduce relative P losses.

The first step in development of the Northeast Region PI score for a field is evaluation of soil test P (STP). Fields with a Morgan (New York) or Modified Morgan (CT, ME, MA, RI, NH) STP exceeding 160 lbs/acre (or greater than 35% P saturation for NH plans that use Mehlich-3) are generally restricted from P application because they are well above the crop response range. Fields with a STP of 100 lbs/acre or lower (22% P saturation or lower) may receive P at rates either limited by crop nitrogen (N) needs or by annual P-crop removal rates, as long as the Northeast Region PI score is less than 100. Fields with a STP from 101 to 160 lbs/acre (Psat between 23 and 35% for NH) can receive P at a P-crop removal limited rate if the Northeast Region PI score is <50.

For fields with a Morgan (New York) or Modified Morgan (CT, ME, MA, RI, NH) STP up to 160 lbs/acre (Psat of 25% or less for NH), the Northeast Region PI first assesses risk of runoff (potential for P transport from the field) based on field attributes. The result of the assessment is a "raw score" (prior to BMP selection). Farmers and planners can reduce the raw score with implementation of BMPs by selecting from options related to: (1) P application method; and (2) ground cover/timing.

If you are interested in participating, contact Quirine Ketterings (qmk2@cornell.edu or 607-255-3061). You can also write to: Quirine Ketterings, Nutrient Management Spear Program, Department of Animal Science, Cornell University, 323 Morrison Hall, Ithaca NY 14853.

Goals

Implementation of a Northeast Region Phosphorus Index Approach.

Funding Sources

NRCS Conservation Innovation Grants and New York State Department of Environmental Conservation.

Additional Resources

Farmer Impact Stories

Fact Sheets

Extension Articles

Journal Articles

  • Ros, M.B.H., Q.M. Ketterings, S. Cela., and K.J. Czymmek (2019). Evaluating management implications of the New York Phosphorus Index with farm field information. Journal of Environmental Quality 48: 1082-1090. doi:10.2134/jeq2019.01.0010.
  • Ketterings, Q.M., S. Cela, A. Collick, S. Crittenden, and K.J. Czymmek (2017). Restructuring the P index to better address P management in New York. Journal of Environmental Quality. doi:10.2134/jeq2016.05.0185.
  • Crittenden, S., Q.M. Ketterings, and K.J. Czymmek (2017). Soil phosphorus saturation ratio sets comparable manure application cutoffs across states differing in agronomic soil test. Soil Science 182:00-00. doi: 10.1097/SS.0000000000000192.
  • Cela, S., Q.M. Ketterings, M., Soberon, C. Rasmussen, and K.J. Czymmek (2017). Upper Susquehanna watershed and New York State improvements in nitrogen and phosphorus mass balances of dairy farms. Journal of Soil and Water Conservation 27: 1-11. doi: 10.2489/jswc.72.1.1.
  • Cela, S., Q.M. Ketterings, K.J. Czymmek, J.L. Weld, D.B. Beegle, and P.J.A. Kleinman (2016). Nutrient management planners' feedback on New York and Pennsylvania phosphorus indices. Journal of Soil and Water Conservation 71: 281-288. DOI: 10.2489/jswc.71.4.281.
  • Cela, S., Q.M. Ketterings, K.J. Czymmek, M. Soberon, and C.N. Rasmussen (2015). Long-term trends of nitrogen and phosphorus mass balances on New York dairy farms. Journal of Dairy Science 98: 7052-7070. http://dx.doi.org/10.3168/jds.2015-9776
  • Soberon, M., S. Cela, Q.M. Ketterings, K.J. Czymmek, and C.N. Rasmussen (2015). Changes in nutrient mass balances over time and related drivers for 54 New York dairy farms (2015). Journal of Dairy Science 98: 5313–5329. http://dx.doi.org/10.3168/jds.2014-9236.
  • Cela, S., Q.M. Ketterings, K.J. Czymmek, M. Soberon, and C.N. Rasmussen (2014). Characterization of N, P, and K mass balances of dairy farms in New York State. Journal of Dairy Science 97:7614–7632. http://dx.doi.org/10.3168/jds.2014-8467.
  • Ketterings, Q.M. (2014). Extension and knowledge transfer; adaptive management approaches for timely impact. Journal of Agricultural Science, Cambridge. DOI:10.1017/S002185961300066X.
  • Soberon, M.A., Q.M. Ketterings, C.N. Rasmussen, and K.J. Czymmek (2013). Whole farm nutrient balance calculator for New York dairy farms. Journal of Natural Resources and Life Science Education (renamed Natural Sciences Education) 42: 57-67.
  • Ketterings, Q.M., K.J. Czymmek, D.B. Beegle, L.E. Chase, and C.N. Rasmussen (2012). Systematic nutrient (im)balances in dairy farm systems of the Northeast and Mid-Atlantic Regions of the United States. Journal of Agricultural Science. doi:10.5539/jas.v4n11p.
  • Ketterings, Q.M., and K.J. Czymmek (2012). Phosphorus index as a phosphorus awareness tool: documented phosphorus use reduction in New York State. Journal of Environmental Quality. 41(6): 1767-1773 (doi:10.2135/jeq2012.0050).
  • Sharpley, A., D. Beegle, C. Bolster, L. Good, B. Joern, Q.M. Ketterings, J. Lory, R. Mikkelsen, D. Osmond, and P. Vadas (2012). Phosphorus Indices: Why we need to take stock of how we are doing. Journal of Environmental Quality 41(6): 1711-1719. (doi:10.2135/jeq2012.0040).
  • Kleinman, P, K. Saacke Blunk, R. Bryant, L. Saporito, D. Beegle, K. Czymmek, Q.M. Ketterings, T. Sims, J. Shortle, J. McGrath, F. Coale, M. Dubin, D. Dostie, R. Maguire, R. Meinen, A. Allen, K. O’Neill, L. Garber, M. Davis, B. Clark, K. Sellner, and M. Smith (2012). Managing manure for sustainable livestock production in the Chesapeake Bay Watershed. Journal of Soil and Water Conservation. 67(2): 54-61. (doi:10.2489/jswc.67.2.54A).
  • Ketterings, Q.M., K.J. Czymmek, and S.N. Swink (2011). Evaluation methods for a combined research and extension program used to address starter phosphorus fertilizer use for corn in New York. Canadian Journal of Soil Science 91(3): 467-477.
  • Maguire, R.O., P.J.A. Kleinman, C. Dell, D.B. Beegle, R.C. Brandt, J.M. McGrath, and Q.M. Ketterings (2011). Manure application technology in reduced tillage and forage systems; a review. Journal of Environmental Quality 40(2): 292-301.
  • Chunyu, S., and Q.M. Ketterings (2010). Impact of soil temperature and moisture on Mehlich-3 and Morgan soil test phosphorus. Soil Science 175(10): 511-518.
  • Grandt, S., Q.M. Ketterings, A.J. Lembo Jr., and F. Vermeylen (2010). In-field spatial variability of soil test phosphorus and implications for agronomic and environmental phosphorus management. Soil Science Society of America Journal 74:1800-1807.
  • Swink, S.N., Q.M. Ketterings, L.E. Chase, and K.J. Czymmek, and J.C. Mekken (2009). Past and future phosphorus balances for agricultural cropland in New York State. Journal of Soil and Water Conservation 64(2):120-133.
  • Haden, V.R., Q.M. Ketterings, and J.E. Kahabka (2007). Factors affecting the change in soil test P levels following manure and fertilizer application. Soil Science Society of American Journal 71: 1225-1232.
  • Brock, E.H., Q.M. Ketterings, and P.J.A. Kleinman (2007). Measuring and predicting the phosphorus sorption capacity of manure amended soils. Soil Science 172: 266-278.
  • Brock, E.H., Q.M. Ketterings, and P.J.A. Kleinman (2007). Phosphorus leaching through intact soil cores as influenced by type and duration of manure application. Nutrient Cycling and Agroecosystems 77: 269-281. DOI: 10.1007/s10705-006-9065-3.
  • Sato, S., D. Solomon, C. Hyland, Q.M. Ketterings, and J. Lehmann (2005). Phosphorus speciation in manure and manure-amended soils using XANES spectroscopy. Environmental Science and Technology 39: 7485-7491.
  • Lehmann, J., Z. Lan, C. Hyland, S. Sato, D. Solomon, and Q.M. Ketterings. Long-term dynamics of phosphorus forms and retention in manure-amended soils (2005). Environmental Science and Technology 39: 6672-6680.
  • Ketterings, Q.M., S.N. Swink, G. Godwin, K.J. Czymmek, and G.L. Albrecht (2005). Maize silage yield and quality response to starter phosphorus fertilizer in high phosphorus soils in New York. J. Food, Agriculture and Environment 3: 360-365.
  • Ketterings, Q.M. and M. Flock (2005). Comparison of Bray-1 and Mehlich-3 tests in high phosphorus soils. Soil Science 170: 212-219.
  • Ketterings, Q.M., J. Kahabka, and W.S. Reid (2005). Trends in phosphorus fertility of New York agricultural land. Journal of Soil and Water Conservation 59: 10-20.
  • Ketterings, Q.M., K.J. Czymmek, W.S. Reid and R.F. Wildman (2002). Conversion of modified Morgan and Mehlich-III soil tests to Morgan soil test values. Soil Science 167: 830-837.