Common Reed (Phragmites australis) Response to Mowing and Herbicide Application

Abstract

AbstractCommon reed is an invasive species that has overtaken wetland habitats in the eastern United States and can spread into roadsides, turf, and ornamental sites. The postemergence grass herbicides used in nursery crops and turf, clethodim, fenoxaprop, fluazifop, and sethoxydim, did not control common reed. Dithiopyr, MSMA, and quinclorac also did not control this weed. Glyphosate applied at 2.24 kg ai/ha (2.0 lb ai/ac) was more effective in preventing regrowth of common reed than glufosinate at 1.12 kg/ha (1.0 lb ai/ac). Mowing every 2, 4, or 8 wk controlled common reed 93, 81, and 69%, respectively, by the end of the growing season, but only reduced regrowth by approximately 55% the following May. Applying glyphosate at 2% v/v either 1 mo after a mowing or 2 wk prior to mowing reduced common reed regrowth the following May by approximately 90%. Applying glyphosate without mowing provided similar common reed control the following spring compared to glyphosate combined with a single mowing. Common reed regrew in all treated plots 1 yr after study initiation, indicating that control treatments must be repeated if common reed is to be eradicated from a site.