High Rock Lake Watershed: Agricultural Study Deanna L. Osmond Department of Soil Science, NC State University and Kathy Neas NCDA&CS, Statistics Division/ USDA-National Agriculture Statistics Service

High Rock Lake Watershed

High Rock Lake Watershed Land Use

What We Wanted to Know What crops are grown? Do farmers soil test? What is the rate of fertilizer application? What is the rate of organic waste application? What are erosion rates? What conservation practices do farmers use? How many buffers exist? What are the livestock types and rates? Farm demographics

How Was the Survey Conducted? Area Frame Sampling Acreage and crops by county Fertilizer or animal waste application rates Nutrient management practices Soil testing and soil test P Conservation practices Erosion rates Livestock types and amounts Demographics Thanks to Charles Proctor and Steve Pratt

Results of High Rock Lake Agricultural Survey

Basic Information Fields selected –1523 agricultural fields sampled –49 fields not sampled due to refusals, inaccessibility or not being agricultural Average field size = 12.5 acres (<1 – 244 acres) Producers –Demographics 51% agriculture was primary income source 36% agriculture was secondary income source –Nutrient Management Behavior 75% farmers make their own nutrient management decision; 70% apply their own nutrients 13% farmers do not add fertilizer

CountyCrop Type Acreage (%) PastureHayCrop Alexander72226 Caldwell Davidson33 34 Davie53839 Forsyth Iredell Rowan Stokes Surry Watauga100-- Wilkes64333 Yadkin83953

Erosion Rates, Soil Sampling, and Soil Test Phosphorus (P) Average erosion is very low (0.6 ton per acre) 95% of farmers soil test Average soil test phosphorus ranges from medium (34) to very high (218) Some soils need phosphorus Some soils do not need phosphorus

Best Management Practices ~75% of all fields with streams had buffers Range 100% to 52% Average buffer width > 200 feet ~70% of all tilled fields in conservation tillage

Nitrogen Application Fescue hay = 22 lb N ac -1 –55% of the 448 hay fields are fertilized, whereas 45% are NOT Fescue pasture = 17 lb N ac -1 –31% of the 531 fields are fertilized, while 69% are NOT Soybeans = 10 lb N ac -1 Other crops at recommended N rates Nitrogen applications relative to crop needs are less than the recommended nitrogen application rates due to large land areas in pasture and hay

Phosphorus Application 60% of the fields were NOT fertilized with P 40% of the fields were fertilized with P –When farmers apply P, they do not always follow soil test P recommendations. This is often due to the nutrient imbalance in animal waste.

Organic Applications Organic applications to acres (~12%) –85% poultry (87% applied to hay or pasture) –15% dairy (60% applied to hay or pasture) Counties with organic applications: Alexander, Caldwell, Davidson, Iredell, Rowan, Stokes, Surry, Wilkes, and Yadkin Nitrogen application range of10 lb ac -1 yr -1 to 239 lb N ac -1 yr-1 (less than or equal to N recommendation Phosphorus application range of 10 lb ac -1 yr -1 to 239 lb ac -1 yr -1

Livestock Majority of animals are cattle but we found horses, goats, sheep, llamas, donkeys, buffalo, alpacas, mules, pigs, and chickens (non-commercial) Average livestock density is appropriate for all counties except Caldwell, Davie, Forsyth, and Surry

North Carolina Nutrient Assessment Tool (NCANT) Low nitrogen losses Phosphorus loss ratings for all counties were low, except Alexander (medium) W)

Conclusions Mostly low intensity agriculture Cropping systems lead to low erosion Buffers frequent Most fields under fertilized, particularly for nitrogen High use of soil testing –Average county soil test phosphorus is high/very high Nutrient loss tool for cropland and pasture suggests that N and P losses from agricultural fields are low

Can Improvements Be Made? Limited opportunities for conservation practices include: Additional buffers or livestock exclusion Reduced stocking rates in some fields Match phosphorus applications with crop phosphorus needs

Questions? Thanks to: NCDA&CS Enumerators Producers NCDENR EPA funds