Goosegrass Management

DR. LARRY STECKEL AND GAVIN SPARKS

JACKSON, TENNESSEE

The typical delayed planting spring did not occur this year. This is good news from a goosegrass management standpoint as it has cut down on the number of fields that crop scouts and producers find infested with large goosegrass.  We are all well versed that there are few good answers when goosegrass gets big.

 Two studies were conducted in Gibson County to get an idea of which herbicides are still an option for goosegrass. Herbicide treatments were applied when goosegrass was 2-4” in height. Very early on it was obvious each population responded differently to the treatments evaluated. The Rutherford population was clearly a glyphosate-resistant (GR) population while the Milan population was readily controlled with glyphosate (GS). At 14 days after application (DAA), Gramoxone + NIS appeared to be the best option for both populations controlling 82 and 97% of the goosegrass for the GR and susceptible (GS) populations. However by 21 DAA, more regrowth was seen then one would like.  Clethodim and clethodim + glyphosate provided the best goosegrass control at 21 DAA.

 Though it took 21 days to provide full control, clethodim showed the best results across both populations (Figure 1). Glufosinate provided the worst control and also reduced goosegrass control when tankmixed with clethodim or glyphosate.  This was suprising as in past years our research would suggest that glufosinate does not reduce grass control. In GS areas glyphosate is still beneficial to have in the tank but where GR is known there is no additional benefit to goosegrass control. Paraquat is another option and acceptable control was observed at 14 DAT, but the bigger the grass the more regrowth and decreased control should be expected.  ∆

 DR. LARRY STECKEL AND GAVIN SPARKS

UNIVERSITY OF TENNESSEE