Postemergence control of annual bluegrass with mesotrione in Kentucky bluegrass

Annual bluegrass (Poa annua L. var Hausskn Timm) is a common grass weed species in turf. A lack of environmental stress tolerance, combined with prolific seed production and a highly competitive growth habit makes annual bluegrass difficult to maintain, but also difficult to get rid of from an established area by a turf manager. Cultural control options rely on increasing the competiveness and health of the desired turf species, such as Kentucky bluegrass, but the management demands for turf areas such as golf course fairways, tees, and greens, favor annual bluegrass. Under these conditions chemical control of the weed is currently the only viable option. The postemergence control of annual bluegrass with an herbicide is difficult. The number of herbicides available for use in cool-season turf is limited, and the ones that are available, selectively control annual bluegrass in a few turfgrass species and lack adequate selectivity. Mesotrione is an herbicide with postemergence control of many broadleaf and grass weed species. An HPPD-inhibiting herbicide, mesotrione causes the destruction of plant tissues by increasing free radicals and reactive oxygen species through the inhibition of carotenoids and other radical scavenging compounds. Herbicide sensitivity is based upon rates of metabolism. Annual bluegrass shows sensitivity to mesotrione and may be able to be controlled by postemergence applications. Studies were conducted at the Landscape Horticulture Research Center in Urbana, Illinois to determine whether mesotrione can be used to control annual bluegrass. Studies were initiated to determine the best rate and application frequency of mesotrione in 2010. In 2011, a series of experiments were conducted to determine the effect of nitrogen fertilization, spray volume, and adjuvants on annual bluegrass control. Conclusions from these studies include a need of multiple, frequent applications of mesotrione to control annual bluegrass; temperature influences mesotrione activity; increasing nitrogen fertility, lower spray volumes, and adding urea-ammonium nitrate solution all increase control. Utilizing these strategies can have negative consequences including possible increased levels of injury to desirable species and spray drift. Mesotrione can be used to control annual bluegrass in cool-season turf, but turf managers must balance the risks and rewards of using mesotrione.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Crop Sciences

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2012

Author dc:creator

• Skelton, Joshua

Contributors dc:contributor

• Branham, Bruce E.

• Mesotrione
• Poa annua
• spray volume
• fertilizer

Statement dc:rights

• Copyright 2012 Joshua Skelton

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/31047

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/31047