2009-11-30_PERMIT FILE - C1981038 (5)

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Volume 7 Exhibit 5 Quick Facts... Phosphorus is the most. limiting nutrient for alfalfa production. Apply phosphate fertilizers for establishing new stands at rates based on soil test results. Incorporate broadcast applications of phosphate fertilizers into the soil prior to :seeding. Apply nitrogen fertilizers for establishing new stands of irrigated forage crops and annual applications for perennial grasses at rates based on NO N levels in the soil. Most Colorado soils contain sufficient available potassium and..sulfur'for forage production. re/x� v • Putd«g Knosdedge to Work Q Colorado State University Cooperative Extension. 3198.. Reviewed 5/05. www.ext.colostate.edu C R 0 P S E R I E S 1 � Fertilizing Alfalfa and Grasses no, 0.537 by J.G. Davis, D.H. Smith and R.L. Croissant' Adequate soil fertility is one of the requirements for profitable forage production.. Alfalfa is the most productive of the forages. It is moderately tolerant of soil salinity, but should not be planted on soils with a salinity greater than 5.decisiemens per. meter (dS /m.), which is equivalent to the same value in millimhos/cm. Alfalfa biologically fixes nitrogen (N) from the air, so N fertilizers generally are required only for.new seedlings during early establishment., If a companion crop is used for establishing a new stand, some fertilizer may be required if soil levels of NO N are low. Phosphorus (P) generally is the most limiting nutrient for alfalfa production, while potassium (K) usually is not limiting in Colorado soils. Before establishing a stand, soils should be tested to determine the soil fertility status so appropriate fertilizers can be applied and properly incorporated.. For more information on fertility requirements and cultural practices for alfalfa, refer to fact sheet 0.703, Alfa far Production and Management. Soil Sampling The value of a soil test in predicting nutrient availability during the growing season is directly related to how well the soil sample collected represents. :the area sampled. Take soil samples prior to seedling establishment so P fertilizers may be incorporated into the sail. For established stands, sample in the early fall so P fertilizers can -be topdressed prior to winter. Take surface samples from the 1 -foot soil depth. .A good sample is a composite of 15 to 20 soil cores taken from randomly selected sites across a uniform soil type. Sample separately areas with major differences in soil properties or management practices.. Thoroughly dry all soil samples within 12 hours after sampling by spreading the soil on clean paper or any other clean surface where the soil will not be contaminated. Do not oven dry thesoil because this will change the soil test results. Ship the air- dried soil in a clean sample container to the soil test laboratory: Submit a carefully completed information sheet with the soil sample. This form provides information so fertilizer application suggestions can be tailored to each specific situation. For existing.stands, periodically test soils for nutrient analysis for optimum P nutrition. More detailed explanations of the importance of taking proper soil samples are found in 0.500, Soil Sampling, 0.501, Soil Testing, and 0.502, Soil Test Explanation. These.fact sheets are available at your Colorado State University County Extension office or from the Cooperative Extension Resource Center, 115 General Services Building, Colorado State University, Fort Collins, CO 80523; (970) 491 - 6198.. TI? - r9pp'old 30 •