Foxtail control in small grains
Making the decision on whether to control foxtail in small grains is not always easy. Research has shown that low populations of foxtails often do not decrease wheat and barley yields, however; heavy foxtail infestations can cause harvest problems (especially when straight combining) and can cause dockage when the grain is delivered to the elevator.
There are some situations when the cost of a herbicide treatment for foxtail control is not justified. These situations would include:
1. When foxtail infestations are low - Less that 20 plants per square foot.
2. When the foxtail emerges after the crop is in the 3- to 4-leaf stage. This is especially
true for barley. Once the small grain is in the 3- to 4-leaf stage, it can usually out compete foxtail, thereby making a herbicide treatment unnecessary. However, if the foxtail population is heavy (30 plants per square foot or more) control may be needed.
Moisture stress is another factor that complicates this situation. Foxtails will cause greater yield losses under drought conditions; therefore, foxtail control is more important in droughty fields.
Making the decision on whether to apply a herbicide for foxtail control is more complicated when the foxtail is emerging with or shortly after the small grain. Some of the options to consider for foxtail control are:
1. If the foxtail infestation is heavy and is emerging with the small grain, consider harrowing or rotary hoeing as soon as possible.
2. If a harrow or rotary hoe is not an option, then consider a herbicide.
3. If the foxtail infestation is light to moderate, then it may be possible to wait and see if the crop will be able to out compete foxtail. If foxtail is still a problem by the time the small grain is in the 4- to 5-leaf stage, grass herbicides can be used for control.
The following is a more in depth discussion on the control options for foxtail about harrowing or rotary hoeing. It is important to consider all methods of foxtail control. Harrowing or rotary hoeing the field can be an effective method of foxtail control if it is done when foxtail is just emerging. Once foxtail is in the 2- to 3-leaf stage, harrowing or rotary hoeing will not give effective foxtail control. Small grains can be harrowed or rotary hoed until the 3- to 4-leaf stage with little effect on yield.