With autumn the key time for tackling invasive weeds, such as Japanese Knotweed and Rhododendron, amenity managers can rely on Roundup®.
Japanese Knotweed is probably the most invasive plant in Britain and is scheduled under the 1981 Wildlife and Countryside Act so that it is an offence to plant or cause it to grow in the wild.
Roundup® Technical Specialist Tom Scanlon advises: “Many areas of the country have campaigns to eradicate the alien weed and Roundup® ProVantage plays an important role by controlling it with maximum safety to operators, the public and the environment.
“As with most broad-leaved perennials, optimum control will be achieved from treatment at flowering in August or September but before die-back. Treatment late in the season is the most effective because the glyphosate is transported deep down into the underground rhizome structure along the natural flow of plant nutrients down for winter storage.”
Rhododendron, (Rhododendron ponticum), brought to the UK by the Victorian plant hunters, was widely planted throughout upland Britain and has escaped into woodland, scrub and open country. High densities can greatly reduce biodiversity and more recently Rhododendron plants have been identified as major reservoir for tree diseases Phytophthora ramorum, and Phytophthora kernoviae. Since 2009 the spread of the fatal disease to Japanese Larch, (Larix kaempferi) has been widely linked to Rhododendron.
“There are several methods of controlling Rhododendron using Roundup® ProActive,” Mr Scanlon explains. “Overall spraying is not suitable for larger plants or for thick stands, as it is difficult to spray and the older plants tend to be less susceptible. Taller bushes must first be cut back to ground level and the cut stumps treated immediately using the cut stump method or the foliage left to re-grow for 2-3 years and sprayed.”
Best practice in application is also important, he comments.
“Operators should pay close attention to correct water volumes and proper sprayer calibration, choosing appropriate nozzles and avoiding drift for optimum efficacy.”
For more information visit the website: www.monsanto-ag.co.uk contact the Technical Helpline on (01954) 717575 or e-mail firstname.lastname@example.org