As a result, most growers have adopted practices that minimize or eliminate tillage. Mowing or flailing controls the height of vegetation within the alleyway and can influence shifts toward preferred vegetation. Regular mowing intervals are required to minimize mowing time, prevent excess clippings, and reduce root competition with the crop. Some grasses including many of the fine and creeping fescues require extra horsepower and sharp cutting blades because of the fiber and toughness of the foliage. Mowing selected, low-g rowing vegetation within the tree row is being considered using adapted equipment that fits under tree limbs.
Flails are a series of rotating knives on a shaft that cut vegetation very near the soil surface.
Moisture loss from weeds is diminshed until regrowth occurs. Flailing also can hasten early season dormancy of some sods, thus reducing water use on som e sites. Prostrate weeds such as spotted catsear or false dandelion, prostrate knotweed, and others often become established when competition from the grass sod is reduced due to flailing. Herbicides selectively control unwanted vegetation within the crop. Agricultural chemicals require considerable testing to assess potential hazards and to minimize possible crop injury before they can be registered and sold for use in specified or labelled crops.