Ordinary knife equipment commonly is used or special applicators sometimes are available. Wheat roots do not extend very far laterally, so ammonia must be applied at narrow spacings. Irregular growth often results when spacing is greater than 20 inches. While limited research information is available on the value of these methods of application, many producers have used these methods with success. There are, however certain precautions.
Ammonia losses can be great if the application is shallow, especially in very dry or very wet soils.
Machine width, depth of operation, speed of travel, soil conditions, soil type and topography are a few factors that influence loss. Sweeps usually are run deeper than rod weeders, so the probability of ammonia gas loss should be less with sweeps. The success of any fertilization method depends greatly on how the equipment is operated and how it is maintained. This especially is true when dry fertilizer is applied with spinner-type bulk spreaders. It is common for these types of spreaders to spread fertilizer unevenly, causing alternate green and yellow strips throughout a field.