Cutless* is a foliar applied and root absorbed plant growth regulator (PGR) for turf that reduces foliar shoot growth on a variety of turfgrass species. Cutless reduces shoot growth by interrupting the functions of gibberellic acid, and thus shortening the internodes, which reduces or slows the turfgrass's rate of growth, but does not impact its long-term development. Rather, using Cutless provides key benefits to treated turfgrass.
These benefits include:
Increased turf density
Improved turf color
Reduced water use
Up to 50% reduction in mowing
Up to 50% fewer clippings
Suppresses Poa annua (annual bluegrass) populations in perennial turfgrasses
Additionally, Cutless is the leading turf PGR for Poa annua suppression. Cutless selectively suppresses the growth of annual bluegrass to a greater degree than desirable perennial turfgrasses, such as creeping bentgrass, shifting the competitive growth advantage away from Poa annua and towards creeping bentgrass. Therefore, over time, creeping bentgrass is able to grow laterally or “creep” into the suppressed Poa annua stand, resulting in successful conversion. This allows for a consistent and gradual conversion from Poa annua to creeping bentgrass with minimal disruption to the playability of the turfgrass. Programmed applications of Cutless have shown to reduce Poa annua populations by as much as 50 - 80% in the first year!
Impact of Cutless on turf growth
How Cutless works. Because it is antagonistic to both the formation and action of growth-promoting gibberellic acid in plants, Cutless causes a reduction in internode elongation. This makes turf more compact and lower growing.
Root effects and tillering. Cutless has no adverse effects on turfgrass root systems and helps encourage more tillers and stolons, with the net effect of increasing turf density.
Water use. Cutless reduces the leaf area of turfgrass plants. The smaller leaf area results in less water loss due to transpiration. In university tests, Cutless treatments resulted in water conservation from 11% to 29% compared to mowed untreated grass.
Color. At the peak of Cutless' growth effects, the grass turns a darker green color.
Cutless and turfgrass cultural practices
During the period of modified growth of Cutless treated turfgrass, changes in the following cultural practices can be expected.
Because Cutless treated grass grows at a slower rate; it takes longer to reach normal mowing height. This reduces both mowing requirement and the quantity of grass clippings. If normal practice returns clippings to the ground, there will be less clipping residue and unsightly clumps of freshly mowed grass will be reduced or eliminated. Reduced volume of clippings also may slow the buildup of thatch in turfgrass.
Cutless treated turfgrass transpires less, resulting in less water used than on similar untreated grass, so irrigation frequency can be reduced. Research has demonstrated that Cutless treated turf can use up to 29% less water compared to untreated turf.
Research has shown that Cutless will inhibit the growth of a number of troublesome broadleaf weeds, including prostate and spotted spurge, oxalis, clover, veronica, henbit and ground ivy. Additionally, Cutless will inhibit growth of some annual grasses—including Poa annua, crabgrass, goosegrass, foxtail and annual sedges.