Ryegrass Control trial

Introduction

Numerous sulfonylurea urea herbicides are registered for the control of ryegrass in warm season turf. Previous research had shown that there was a synergy when a relatively small amount of Destiny (iodosulfuron-methyl-sodium) is added to Tribute (foramsulfuron). This resulted in faster and improved ryegrass control.

This trial was established in Western Sydney to compare different sulfonylurea urea herbicide treatments on the removal of ryegrass from couch grass.

Treatments

No Chemical Rate Date
1 Untreated Control - -
2 Tribute 1.5 L/ha 20/7/2012
3 Destiny + NIS 150 g/ha 20/7/2012
4 Tribute + 1.5 L/ha 20/7/2012
Destiny + NIS 25 g/ha
5 Destiny + 150 g/ha 20/7/2012
Tribute + NIS 0.5 L/ha
6 Tribute + AMS + Hasten 1.5L/ha 20/7/2012
7 Monument + NIS 30g/ha 20/7/2012

Water rate: 395L/ha NIS = Non-ionic surfactant at 0.25%v/v AMS = Ammonium sulphate at 3kg/ha Hasten at 1% v/v

The results show that a combination of Destiny at the full rate of 150 g and a low rate of Tribute (0.5 L) gave the fastest and best ryegrass control.
The use of ammonium sulphate and Hasten in the USA has been used to improve weed control of sulphonyl urea herbicides in cold temperatures. In this trial these additives did not improve ryegrass control when used with Tribute.

Untreated Control Tribute 1.5 L
Destiny 150 g + NIS Tribute 1.5 L + Destiny 25 g + NIS
Destiny 150 g +Tribute 0.5 L + NIS Tribute 1.5 L + AMS + Hasten
Monument 30 g + NIS  
 
Photos taken in September.