Fertilizer Treatment Problems

1. Nitrogen

a - Higher amount of nitrogen required to achieve large yields can best be applied and utilized by split application.

b - When weather conditions are not conducive to good crop growth (cold-wet), nitrate nitrogen maybe most effective.

2. Nitrogen-Phosphates

In situations where phosphorus uptake is low (causing poor fruit set, poor root development, etc.), ammonium phosphates or nitrogen phosphate mix solutions may be more effective.

3. Potash

All forms of commercially available potash are readily soluble and available. The other element or elements contained in the material to be used may be the deciding factor as to the most desirable source of potash Such materials as potassium nitrate, potassium sulfate, potassium chloride, and sulfate of potash magnesia are all recommended materials. (See Appendix Table 1.)

4. Secondary, and Trace Elements

Use most effective method of application when troubles develop during the growing season. Foliar sprays may need to be used for maximum over-all results. Most micronutrient compounds are soluble. Check with your supplier. Response to soil application may be very limited during first year.

Fertilizer Application In Irrigation Water

Water soluble fertilizers, especially nitrogen, are effectively side-dressed through surface or sprinkler irrigation water. Timing and quantity per acre can be closely controlled for maximum response. However, the following factors must be considered.

1. Only water soluble ancT compatible fertilizers may be used.

2. Uniformity of application can only be as good as the uniformity of the water distribution and ire fiItratEon pattern.

3. Corrosion of irrigation equipment may result unless fertilizer is applied as a very dilute solution {20 parts per million or less).

4. Metering equipment, water control, and delivery equipment must be regulated h assure constant, steady delivery of a uniform solution.

Concentrated fertilizer solutions are frequently the most economic buy in fertilizers, and usually these are liquids. Application by injector rig in some instances is the only way to apply this material, and for some applications it is the best way. Conditions which uniquely favor injection include the following:

1. Volatile material which must be placed under the surface to prevent or minimize losses.

2. Liquid materials which are relatively insoluble in soil solution can be placed down into the root zone effectively by injection.

3. Injection not only effectivity places the material in the root zone but can do so with a minimum of surface disturbance. This can be advantageous in both dryland and irrigated farming, for prevention of moisture loss while fertilizing, pasture renovation, side dress placement on row crops, etc., where surface application would delay crop response.

Where these conditions exist, they may be sufficiently important to warrant the application of a material by injector which would normally be applied by other methods. In the application of fertilizer for crop production there is no universal best methods or materials. This should be kept firmly in mind when applying, writing, or interpreting fertilizer recommendations. Local conditions or individual circumstances can alter any fertilizer program; amounts, methods, or kinds.s

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