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2022 Projects: Phosphorus Index Evaluation in the Northeast

How Can Soil Phosphorus be Better Kept On-farm and out of Waterways?

The original New York Phosphorus Runoff Index (NY-PI) was released in 2001. Version 2.0 of the NY-PI, released in 2019, reflects subsequent gains in knowledge and addresses challenges that were identified since publishing the first NY-PI. The NY-PI 2.0 is a field management tool designed to estimate the relative risk of phosphorus (P) runoff from agricultural fields.

The original NY-PI used a source x transport approach. The NY-PI 2.0 uses a more intuitive transport x best/beneficial management practice (BMP) approach, where fields are scored based on factors that drive transport of manure and fertilizer P from agricultural fields, and scores can be lowered by implementation of BMPs that reduce the risk of P transport.

The NY-PI 2.0 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 NY-PI 2.0 is used to derive a relative risk score for each nutrient management planning cycle based on information garnered from farm records, soil erosion control plans, manure and fertilization plans, and field visits.

The first step in development of the NY-PI 2.0 score for a field is evaluation of soil test P (STP). Fields with a Cornell Morgan STP exceeding 160 lbs/acre 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 may receive P at rates either limited by crop nitrogen (N) needs or by annual P-crop removal rates, as long as the NY-PI 2.0 score is less than 100. Fields with a STP from 101 to 160 lbs/acre can receive P at a P-crop removal limited rate if the NY-PI 2.0 score is < 50.

For fields with a Cornell Morgan STP up to 160 lbs/acre, the NY-PI 2.0 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 NY-PI 2.0 score with implementation of BMPs by selecting from options related to: (1) P application method; and (2) ground cover/timing.

Farms with a whole-farm P balance (3-yr running average) at or below 12 lbs P/acre meet the feasible P balance for dairy farms in New York. These farms can apply manure at N-based rates on fields with a Cornell Morgan STP up to 100 lbs/acre, even if the NY-PI 2.0 assessment for these fields limits rates to P-based, as long as the selected BMPs to get to a P-based score are implemented.

The NY-PI 2.0 reflects farmer and planner feedback on the original NY-PI and earlier versions of NY-PI 2.0. The new PI was tested and further improved with two datasets consisting of: (1) more than 33,000 agricultural fields in New York; and (2) two years of NY-PI and whole-farm P balance information from 18 New York dairy farms.

Comparing NY-PI 1.0 and 2.0, the new PI has an increased capacity to provide additional water quality benefits by, among others, encouraging more ground cover or surface residue on fields, increasing acres where a manure application is placed below the soil surface and/or better timed with crop nutrient uptake, and incentivizing improved whole-farm P balances.

The NY-PI 2.0 replaces earlier runoff estimation tools referenced by the NRCS 590 Nutrient Management Standard and used in Comprehensive Nutrient Management Plans (CNMP) and other conservation planning.

The NY-PI 2.0 was released at the Northeast Region Certified Crop Advisor Training in Syracuse, in December of 2019. Current work focuses on development of additional documentation and software tools to help with implementation of the new NY-PI 2.0 in 2020/2021.

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

Evaluate and improve upon PIs in the Northeast to better address water quality through a combination of stakeholder feedback, modeling, and whole-farm P balances.

Funding Sources

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

Additional Resources

Farmer Impact Stories

Fact Sheets

Extension Articles

  • Czymmek, K.J., Q.M. Ketterings, M. Ros, S. Cela, S. Crittenden, D. Gates, T. Walter, S. Latessa, and G. Albrecht (2020). New York Phosphorus Index 2.0. What's Cropping Up? 30(1): x-xx.
  • Czymmek, K.J., and Q.M. Ketterings (2020). A new Phosphorus Index for NY: Part 2: How the P index works. PRO-DAIRY e-Leader.
  • Czymmek, K.J., and Q.M. Ketterings (2019). A new phosphorus Index for NY: Part 1: What farmers need to know. PRO-DAIRY e-Leader.
  • Ros, M., K.J. Czymmek, and Q.M. Ketterings (2017). Series: Phosphorus and the Environment, 1. An Introduction to Phosphorus
  • Van Amburgh, M., and K.J. Czymmek (2017). Series: Phosphorus and the Environment, 2. Setting the Record Straight: Comparing Bodily Waste Between Dairy Cows and People
  • Czymmek, K.J. (2017). Series: Phosphorus and the Environment, 3. Protecting our lakes: shoreline septic system concerns.
  • Fields, L. (2017). Series: Phosphorus and the Environment 4. Greatly Improved Nutrient Efficiency Demonstrates New York Dairy Farmersí Environmental Stewardship
  • Sadeghpour, A., S. Hetrick, K.J. Czymmek, G. Godwin and Q.M. Ketterings (2016). Managing soil test phosphorus in corn with manure and compost. What’s Cropping Up? 26(5): 86-87.
  • Czymmek, K.J., L. Geohring, Q.M. Ketterings, P. Wright, T. Walter, G. Albrecht, J. Lendrum and A. Eaton (2015). Revised winter and wet weather manure spreading guidelines to reduce water contamination risk. Cornell University Animal Science Publication Series No. 245, Ithaca NY. 8 pages.
  • Soberon, M., S. Cela, Q.M. Ketterings, C. Rasmussen, and K.J. Czymmek (2015). Change in nutrient mass balances over time for 54 New York dairy farms. What’s Cropping Up? 25(3): 22-24.
  • Cela, S., Q.M. Ketterings, K.J. Czymmek. M. Soberon, and C. Rasmussen (2015). Trends in nutrient mass balances on four New York dairy farms. What’s Cropping Up? 25(3): 25-27.
  • Cela, S. Q.M. Ketterings, K.J. Czymmek, M. Soberon, and C. Rasmussen (2015). Feasible whole farm nutrient mass balances for New York dairy farms. What’s Cropping Up? 25(2).
  • Soberon, M. Q.M. Ketterings, K.J. Czymmek, S. Cela, C. Rasmussen (2015). Whole farm nutrient mass balance calculator for New York dairy farms. What’s Cropping Up? 25(2).
  • Czymmek, K.J., and Q.M. Ketterings (2015). Taking care of (manure) business – Strive to do the best possible job every time manure is applied. Eastern DairyBusiness. The Manager. 7(1): 16.
  • Cela, S. Q.M. Ketterings, K.J. Czymmek, M. Soberon, and C. Rasmussen (2014).  Whole farm nutrient balance benchmarks for New York dairies. Cornell Nutrition Conference Proceedings. Syracuse NY, October 21, 2014.
  • Ketterings, Q.M., G. Godwin, W. DeGolyer, and K. J. Czymmek (2013). Manure injection rate study at Table Rock farm. What’s Cropping Up? 23(1): 12-16.
  • Knight, J., Q.M. Ketterings, K.J. Czymmek, and R. Wildman (2012). Phosphorus saturation versus the New York P index? Impact on manure and fertilizer management in New York State. What’s Cropping Up? 22(3): 9-11.
  • Ketterings, Q.M., and K.J. Czymmek (2012). P index survey: what caused impressive improvement in the NYS P Balance? What’s Cropping Up? 22(3):12-15.
  • Ketterings, Q.M., G. Godwin, W. DeGolyer, and K.J. Czymmek (2012). Trial results for manure injection at Table Rock Farm. What’s Cropping Up? 22(2): 17-22.
  • Knight, J., P. Ristow, G. Swanepoel, K. Czymmek and Q.M. Ketterings (2012). Dairy and cash grain farmer perceptions of the value of manure. What’s Cropping Up? 22(1): 3-5.
  • Ristow, P.L., S. Moss, Q.M. Ketterings, K.J. Czymmek (2011). Understanding manure nutrient variability. What’s Cropping Up? 21(4): 19-23.
  • Ketterings, Q.M., K.J. Czymmek, P. Ristow, C. Rasmussen, and S. Swink (2011). State, regional and farm-scale nutrient balances: tools for enhanced efficiency of whole farm nutrient use. 73rd Cornell Nutrition Conference for Feed Manufacturers October 18-20, 2011. Syracuse, NY. Proceedings pages 180-189.
  • Maguire, R., D. Beegle, J. McGrath, and Q.M. Ketterings (2011). Manure injection in no-till and pasture systems. Extension Publication. Mid Atlantic Water Program.
  • Ketterings, Q.M., G. Godwin, S.N. Swink, J. Foster, E. Hong, K.J. Czymmek, A. Wright, M. Hunter, J. Lawrence, S. Canner, C. Albers, A. Gabriel, E. Young, T. Kilcer and P. Barney (2011). Can manure replace the need for starter N fertilizer? What’s Cropping Up? 20(1): 14-17.
  • Czymmek, K.J., and Q.M. Ketterings (2011). Shallow manure incorporation works. Eastern DairyBusiness 3(3): 20.
  • Czymmek, K.J., L. Geohring, J. Lendrum, P. Wright, G. Albrecht, B. Brower, and Q.M. Ketterings (2011). Manure management guidelines for limestone bedrock/karst areas of Genesee County, New York: Practices for risk reduction. Animal Science Publication Series No. 240.
  • Czymmek, K.J, Q.M. Ketterings, L.E. Chase, and L. Goehring (2010). NY Phosphorus Index may not be perfect, but has served state well. Chesapeake Bay Journal; Forum. November 2010 issue.
  • Grandt, S., Q.M. Ketterings, A. Lembo, F. Vermeylen, and K. Czymmek (2010). In-field spatial variability of soil test phosphorus and implications for agronomic and environmental phosphorus management. What’s Cropping Up? 20(3): 8-9.
  • Place, A., Q.M. Ketterings, G. Godwin, J. Lawrence, B. Aldrich, P. Barney, and T. Kilcer (2010). Shallow incorporation of manure minimizes soil disturbance and conserves nitrogen. What’s Cropping Up? 20(3): 3-5.
  • Swink, S.N. Q.M. Ketterings, K.J. Czymmek, L.E. Chase, and J. Mekken (2009). Upper Susquehanna River Watershed cropland P balances. What’s Cropping Up 19(2): 1-3.
  • Place, A., Q.M. Ketterings, G. Godwin, K.J. Czymmek, S. Bossard, P. Barney, J. Lawrence, B. Aldrich, T. Kilcer (2009). Comparing manure incorporation methods in reduced till systems. What’s Cropping Up 19(2): 4-5.
  • Ketterings, Q.M., and K.J. Czymmek (2009). Getting a good read on P. Eastern DairyBusiness 1(2): 21 (+23).
  • Swink, S., Q.M. Ketterings, K. Czymmek and L. Chase (2009). Dairies improve P management. The Manager. Eastern Dairybusiness 1(1): 20-21.
  • Bruulsema, T. and Q.M. Ketterings (2008). Best management for fertilizers on Northeastern dairy farms. IPNI. 7 pages.
  • Swink, S., Q.M. Ketterings, K.J. Czymmek, and L.E. Chase (2008). Proactive agricultural and environmental management by New York dairy farmers greatly reduced cropland P balances. What’s Cropping Up? 18(5): 1-4.
  • Ketterings, Q.M., J.H. Cherney, K.J. Czymmek, E. Frenay, S.D. Klausner, L.E. Chase, and Y.H. Schukken (2008). Manure use for alfalfa-grass production. Department of Animal Science Mimeo 231/Department of Crop and Soil Sciences Extension Series E08-3. Cornell University. 43 pages.
  • Lawrence, J. Q.M. Ketterings, S. Bossard, K. Czymmek (2007). Manure N conservation with chisel plow versus Aerway incorporation. What’s Cropping Up? 17(4): 1-3.
  • Haden, R., Q.M. Ketterings, J. Kahabka, and K.J. Czymmek (2007). How quickly will soil test P levels increase? What’s Cropping Up? 17(3): 3-4.
  • Ketterings, Q.M., and K.J. Czymmek (2007). New York corn producers make a difference! Phosphorus fertilizer imports 2003-2005 reduced by 26.7 million lbs of P2O5. What’s Cropping Up? 17(2): 4.
  • Ketterings, Q.M., K.J. Czymmek, S. Swink (2007). The state of New York’s phosphorus balance. The Manager. Northeast DairyBusiness 9(2): 20-21.
  • Ketterings, Q.M., E. Frenay, J.H. Cherney, K.J. Czymmek, S. Klausner, L.E. Chase, and Y.H. Schukken (2006). Application of manure to established stands of alfalfa and alfalfa-grass (2006). In: Field Crop Dealer Meetings, Department of Crop and Soil Sciences Extension Series No E06-4, October 24-27, 2006. p 515.
  • Mekken, J.C., S.N. Swink, and Q.M Ketterings (2006). Statewide and country-based phosphorus balances for New York State. Department of Crop and Soil Sciences Extension Series E06-03. Cornell University, Ithaca, NY. 126 pages.
  • Ketterings, Q.M., G. Godwin, T.F. Kilcer, P. Barney, M. Hunter, J.C. Cherney, and S. Beer (2006). Nitrogen, phosphorus, and potassium removal by brown midrib sorghum sudangrass. What’s Cropping Up? 16(1): 4-6.
  • Rasmussen, C.N., Q.M. Ketterings, G. Albrecht, L. Chase, and K.J. Czymmek (2006). Mass nutrient balances – a management tool for New York dairy and livestock farms. In Silage for Dairy Farms; Growing, Harvesting, Storing, and Feeding. NRAES Conference. Harrisburg, PA, January 23-25. Pages 396- 414.
  • Rasmussen, C.N., Q.M. Ketterings, J. Mekken, K.J. Czymmek and L.E. Chase (2005). Statewide and whole farm phosphorus balances- tools to help with long-term nutrient planning on dairy and livestock farms. What’s Cropping Up? 15(6): 7-9.
  • Ketterings, Q.M., C. Rasmussen, J. Mekken, and K. Czymmek (2005). Statewide, County-based and whole farm nutrient balances. Tools to help with long-term nutrient planning. In: Field Crop Dealer Meetings, Department of Crop and Soil Sciences Extension Series No E05-1, October 25-28, 2005. pages 19-21.
  • Ketterings, Q.M., and K.J. Czymmek (2005). How much P is enough? Nutrient Management. April 2005. The Manager. Northeast Dairy Business 7(4): 37 and 39.
  • Czymmek, K.J., Q.M. Ketterings, J. Ten Eyck, and T. Horvath (2005). The New York CAFO Program: successfully connecting science, policy, regulation, and implementation. New York Water Environmental Association Inc. Clearwaters Magazine 35(1): 27-28.
  • Czymmek, K.J., Q.M. Ketterings, and G.L. Albrecht (2005). Dairy producers: is it time to take a look at your phosphorus fertilizer rates for corn? Small Farms Quarterly Spring 2005 (April 11, 2005). Page 8.
  • Czymmek, K.J., D. Beegle, and Q.M. Ketterings (2005). Implications of agronomic and environmental considerations in land application of manure in dairy farm systems of the Northeast and Mid-Atlantic Regions of the United States. NRAES Conference. March 15-17, 2005. Dairy Manure Management: Treatment, Handling and Community Relations. NRAES-176. pp 1-10. Also appeared in Ag Nutrient Management 2(2)(2006): 6-12.
  • Czymmek, K.J., L.D. Geohring, Q.M. Ketterings, P. Wright, and A. Eaton (2005). Supplemental manure spreading guidelines to reduce water contamination risk during adverse weather conditions. What’s Cropping Up? 15(3): 1-3.
  • Ketterings, Q.M., J.H. Cherney, T.F. Kilcer, and P. Cerosaletti (2005). Phosphorus removal by brown midrib sorghum x sudangrass. What’s Cropping Up? 15(1): 5-7.
  • Ketterings, Q.M., G. Albrecht, M. Hunter, P. Carey, S.N. Swink, and K.J. Czymmek (2004). Whole farm corn starter phosphorus fertilizer imports. What’s Cropping Up? 14(6): 3-5.
  • Ketterings, Q.M., J.E. Kahabka, and W.S. Reid (2004). The phosphorus fertility status of New York agricultural land. What’s Cropping Up? 14(5): 3-6. (Also appeared as abstract in Field Crop Dealer Meetings, October 26-29, 2004. CSS Extension Series No. E04-33, October 2004).
  • Ketterings, Q.M., S. Swink, G. Godwin, K.J. Czymmek, and G. Albrecht (2004). New York Starter Phosphorus Project: Does starter P fertilizer impact silage quality? What’s Cropping Up? 14(5): 1-2.
  • Ketterings, Q.M., S. Swink, G. Godwin, K.J. Czymmek, A. Durow, and G.L Albrecht (2004). New York Starter Phosphorus Project – Results of the 2003 growing season. What’s Cropping Up? 14(1): 1-3.
  • Whole farm nutrient management on dairy farms to improve profitability and reduce environmental impacts (2004). Department of Crop and Soil Sciences Research Series R04-1 and University of Wisconsin Extension Publication A3794. Report on collaboration among Cornell University, University of Wisconsin-Madison, and USDA-ARS Dairy Forage Research Center.  April 2004.
  • Ketterings, Q.M., G.L. Albrecht, and K.J. Czymmek (2003). Whole farm crop and manure nutrient management. Help! In: Proceedings 2003 Cornell Nutrition Conference. Department of Animal Science, Cornell University. October 21-23, 2003. Pages 245-250.
  • Ketterings, Q.M., K.J. Czymmek, S. Swink, G. Albrecht, G. Godwin, and A. Durow (2003). New York State Starter Phosphorus Project. In: Field Crop Dealer Meetings. Department of Crop and Soil Sciences Extension Series E03-25. Pages 11-12.
  • Czymmek, K.J., Q.M. Ketterings, L.D. Geohring, and G.L. Albrecht (2003). New release: New York phosphorus index: user’s manual and documentation. What’s Cropping Up? 13(4): 7.
  • Ketterings, Q.M., K.J. Czymmek, and S.D. Klausner (2003). Phosphorus guidelines for field crops in New York. Second Release. Department of Crop and Soil Sciences Extension Series E03-15. Cornell University, Ithaca, NY. 35 pages.
  • Czymmek, K.J., Q.M. Ketterings, L.D. Geohring and G.L. Albrecht (2003). New York State Phosphorus Runoff Index. CSS Extension Bulletin E03-13. 72 pages.
  • Ketterings, Q.M., T. Byron, G. Godwin and K.J. Czymmek (2003). Phosphorus Starter Project – Results of the 2002 growing season. What’s Cropping Up? 13(1): 4-6.
  • Ketterings, Q.M. and K.J. Czymmek (2002). Phosphorus soil testing and nutrient management planning in New York. What’s Cropping Up? 12 (4): 1-3.
  • Byron, T.M., Q.M. Ketterings, and K.J. Czymmek (2002). Phosphorus starter demonstration project. Results of the 2001 growing season. What’s Cropping Up? 12 (2): 4-5.
  • Ketterings, Q.M., T. Byron, and K.J. Czymmek (2001). P starter demonstration/research project – 2001. In: Field Crop Dealer Meetings. Department of Crop and Soil Sciences Extension Series E01-7. Pages 3-6.
  • Ketterings, Q.M., B. Bellows, K.J. Czymmek, W.S. Reid, and R.F. Wildman (2001). Do Modified Morgan and Mehlich-III P have a Morgan P equivalent? In: Field Crop Dealer Meetings. Department of Crop and Soil Sciences Extension Series E01-7. Pages 15-19.
  • Ketterings, Q.M., K.J. Czymmek, and S.D. Klausner (2001). Phosphorus recommendations for field crops in New York. Department of Crop and Soil Sciences Extension Series E01-5. Cornell University, Ithaca, NY. 32 pages.
  • Czymmek, K.J., Q.M. Ketterings, and L.D. Geohring (2001). Phosphorus and Agriculture VIII: The New Phosphorus Index for New York State. What’s Cropping Up? 11(4): 1-3.
  • Czymmek, K.J., L.D. Geohring, and Q.M. Ketterings (2001). What’s the risk of phosphorus runoff from your fields? Northeast DairyBusiness 3(8): 26-28.
  • Ketterings, Q.M., B.C. Bellows, K.J. Czymmek, and W.S. Reid (2001). Conversion Equations Part 2: Do Mehlich-III K, Ca, and Mg have Morgan equivalents? What’s Cropping Up? 11(4): 4-5.
  • Ketterings, Q.M., B. Bellows, K.J. Czymmek, W.S. Reid, and R.F. Wildman (2001). Do modified Morgan and Mehlich-III P have a Morgan equivalent? What’s Cropping Up? 11(3): 2-3.
  • Czymmek, K., J. Degni and Q.M. Ketterings (2001). Phosphorus starter demonstration project. Results of the 2000 Growing Season. What’s Cropping Up? 11(3): 4-6.

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., 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., J.H. Cherney, T.F. Kilcer, and P. Cerosaletti (2004). Phosphorus removal by sorghum sudangrass in Northeastern USA. Online. Forage and Grazinglands DOI:10.1094/FG-2004-1015-01-RS.
  • 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.