Cultivation Usually Pays ----
type of unit less important
Cultivating corn often increases crop yields even where broadcast herbicide applications are made and weed control appears adequate. The beneficial effects of cultivation include controlling weed escapes (especially perennials), breaking a soil crust, or loosening compacted soils.
Cultivation should be done when the weeds are relatively small and the crop is large enough (usually 3 to 4 inches tall) to allow for some soil to be rolled into the row without burying the crop. When this is done, the cultivator need not be set any deeper than a couple of inches to dislodge the weeds and little, if any, moist soil will be brought to the soil surface. As time progresses, cultivating depth will be a direct function of weed size. Some growers are concerned that deep cultivation will result in a significant loss of soil moisture. However, weeds are transpiring water through their leaves every day they are alive and this is moisture made unavailable for crop growth. It is always a good strategy to cultivate early when weeds are small and before they have "pumped" a significant amount of moisture into the atmosphere.
During
1990 and 1991, Jerry Doll, UW Extension Weed Specialist, conducted a number
of studies examining cultivator use, timing, and type. Every year a phone
call or two comes into the extension office from a grower wanting to know
if one type of cultivator is more effective than another. The results of
the UW study is presented in Table 1. Note that the S-tine, no-till, rolling,
and C-shank cultivators were all effective in controlling weeds under the
conditions of the study on a silt loam soil. Averaged over the two years,
there were no differences in yield related to the type of cultivator used.
In summary, cultivation is a practice that can replace, complement, and/or
enhance chemical weed control in many situations. Research shows that it
will be cost effective as a routine practice in corn production systems
regardless of cultivator type.
For more information contact Mike
Rankin
|
|