Greenkeepers and turf managers face an ‘explosion’ of broadleaved weeds on golf courses throughout the summer and autumn unless they take adequate precautions, warned Brian Robinson, Director of Agronomy with turf consultancy Grass Science, this week.
“The exceptionally wet conditions in the winter led to thin swards and has created the potential for massive weed problems,” he said. “This coupled with the early summer rainfall means that unless selective herbicides are used in conjunction with a course over-seeding programme, weed populations could be up 35% on a normal year.”
Brian Robinson pointed out that frosts in the New Year compounded the problem by further stressing the grasses and increasing the percentage of wear. “I estimate that wear on some courses could be up 40% on last year,” he said. “As a result, over-seeding will be an important part of maintenance on many courses.”
According to Mr Robinson, as wear is more serious this year, weeds appeared earlier than normal in the thin patches and are competing with grass development. “Another factor favouring weeds is a 50% increase in turf fibre levels,” he said. “Again the wet winter contributed to an increase in dead organic matter and surface roots. As a result, seeds from broadleaved weeds like daisies and plantains are trapped in the fibre, which provides an ideal microclimate for weeds to germinate quickly. This combination of weed competition on thin swards and an increase in fibre has led to an explosion in broadleaved weed populations.”
Brian Robinson recommends an early application of a high quality selective herbicide like Greenor to aid spring sown over-seeding programmes and effectively control problem weeds including clover and daisies.
“The earlier you hit the weeds, the sooner the grass will re-establish as a high quality sward,” he said. “This helps prevent any weed seeds from germinating. Greenor’s micro-emulsion technology makes it particularly safe for use on turf grass.”
Grass Science b.robinson@grass-science.com 01204 366036