Verdict* 520 Herbicide - Couch Grass Control

Couch grass control under vines and trees with Verdict* Herbicide

Couch grass (Cynodon dactylon) has established as a major weed problem of vineyards and orchards in most areas of Australia. The lack of regular cultivation and this weed's ability to spread its tough scaly rhizomes and branching stolons, make couch grass a very difficult weed to control. Translocated, selective herbicides, such as Verdict herbicide, have been found to be the most effective products for the control of couch grass and other grasses while leaving trees and vines unharmed. For many years, Verdict Herbicide has been the largest selling selective grass herbicide in Australia because of its effectiveness in controlling a wide range of annual and perennial grasses and its extensive registrations which include broadacre crops, orchard, vines, ornamentals and plantation cropping situations in Australia.

This latest formulation of Verdict Herbicide, contains 520g/L of haloxyfop-R-methyl which means it has a low use rate, and is an easy to pour and measure product that not only controls couch grass but is also very effective on a range of perennial and annual grass weeds. Verdict Herbicide is absorbed by leaves and roots and is translocated to the growing points where it kills the plant by interfering with the production of fatty acids which are used to produce cell walls and waxes. The relatively small amount of chemical moved beyond the first node, by the plant, and the large number of nodes on the stolon, leads to regrowth being common after a single application. This is the case for all translocated herbicide and is the major problem with couch control. It will be necessary to make more than one application of herbicide to successfully manage couch.

Drip irrigation is becoming common throughout Australian vineyards and orchards because of its effective placement of water and the flexibility it provides in terms of water use and crop management. Couch can become well established around drippers or in the wetter parts of the vineyard or orchard. Couch can also be usually found outside these areas but will most likely be under moisture stress. Applying herbicides to couch that is under moisture stress will result in less than adequate control being achieved. Translocated herbicides, such as Verdict should only be applied to couch which is actively growing and not under moisture stress, ideally they should be applied following a rainfall event of 25mm plus. Verdict Herbicide should be applied at 800 mL/ha for optimum results or 50 mL/100L of water when spraying with a handgun or backpack. It is essential to add an adjuvant to Verdict Herbicide. Best results will be achieved with Uptake* spraying oil at 500 mL/100L of spray solution. A minimum of 200L of water per ha should be used when applying by boom spray to couch. Remember to target the weed when spraying as this ensures thorough coverage and effective weed control. Perennial grasses such as paspalum and Johnson grass and annual grasses which include ryegrass, barley, barnyard, brome, crowsfoot, paradoxa, summer, volunteer cereals, wild oats and storksbill (Erodium spp.) will also be controlled at the 800 mL/ha rate.

When used according to the label directions Verdict Herbicide is safe to vines and tree's of all ages. Which makes it a particularly useful tool in controlling those troublesome grass weeds that thrive during summer when you do not want to damage vines or trees. Verdict Herbicide can also be used around vines and trees with confidence, as there are no harvesting withholding periods.

For further information on Verdict Herbicide and the control of couch or other grasses contact your local Dow AgroSciences representative or your local store.