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Crop Requirements and Nutrient Sources

Adequate nutrition is essential if productive new corn hybrids are to realize their full yield potential. This publication provides fertilizer guidelines based on university research and a special section on manures as nutrient sources for corn.

Manure

Nitrogen, phosphorus or potassium

Secondary and micronutrients

Tillage practices



Alfalfa

Grasses

Legumes

Onions are grown primarily under furrow or drip irrigation in southwest Idaho and are a high value crop. Most of the harvested onions are marketed from storage during the fall, winter and early spring. They represent roughly a third of the onions marketed nationally. Fertilizers historically are used extensively. Onion culture presents special challenges for effective nutrient management. The root system is relatively shallow though roots extend well into the second foot. The soils program at Parma has addressed onion fertilization issues since the 1970s.

Nitrogen

Phosphorus

Effective management of nutrients is critical for potato production, as tuber yield and tuber quality are directly impacted by quantity and timing of nutrient applications. Potatoes have high nutrient demands, as they require approximately 220 lb nitrogen (N), 30 lb phosphorus (P) and 300 lb potassium (K) per acre to produce a 450 cwt./acre yield of Russet Burbanks, a typical yield for southern Idaho.

Copper soils

Cull (waste)

Garden potatoes

Irrigation

Manure

Nitrogen

    Organic

    Phosphorus

    Potassium

    Varieties

    Small grains are important crops throughout Idaho and are grown in diverse production systems ranging from fully irrigated to low rainfall wheat-fallow. Wheat market classes include soft white winter and spring; hard red winter and spring; hard white winter and spring; club; and durum. Wheat is also fed to livestock. Barley is grown for malt, animal feed and human food. Combined small grains represent the second most valuable crop marketed in Idaho. They are valuable for the receipts they provide directly to farms but also are excellent rotation crops for other commodities that may involve higher production costs, marketing risks and income potential. Effective nutrient management is critical for the success of small grains, affecting both production and quality.


    Barley

    Oats

    Residue management

    Triticale


    Wheat

    Fertilizer

    Nitrogen

    Nitrogen is typically the most important nutrient for wheat as it is the most limiting to production. Effective N management is also important to protect groundwater quality. Effective nitrogen management differs for different wheat production systems and marketing classes. Nitrogen application rate, timing, source and method may all influence wheat yield and quality. Quality concerns related to N include grain protein, gluten strength, test weight; and for durum, vitreous kernels.

    Phosphorus

    Phosphorus, potassium and sulfur

    Conservation Tillage Practices

    Manure

    Micronutrients

    Nitrogen

    Phosphorus

    Potassium

    Seed Coating

    Wastewater

    Contact

    University of Idaho Extension

    Phone: 208-934-4417, (c) 208-539-2582

    Email: mdeharo@uidaho.edu

    Web: uidaho.edu/extension/nutrient