PHYSICAL AND CHEMICAL CONTROL OF POA ANNUA ON PROFESSIONAL FOOTBALL PITCHES

摘要

The spread of Poa annua L. on newly constructed, or renovated, professional football pitchesis a well documented problem. As P. annua becomes the dominant grass species in the swardit will form a thatchy, water-retentive surface, which is susceptible to disease and has a tendency to 'kick-out' under play. This will potentially provide problems with the appearance ofthe pitch and its playing quality. The effectiveness of mechanical and chemical treatments which might be used to control the spread of P. annua on a professional football pitch, and their interaction with watering policies, were examined over a period of three years. Control plots showed a spread of P. annua within a Lolium perenne L. sward which reached 45% of the total cover at the end of two years, rising to over 50% after three years. An over-watering treatment, which added 30% more irrigationwater to certain plots, accelerated the spread of P. annua, which reached 55% of the total coverafter two years, but stabilised at this level over the next year. Chemical treatment, based on one or two applications of an ethofumesate herbicide, appeared to provide an effective control for P. annua, keeping the proportion to below 5% of the sward after three years. No significant advantage was evident from using two applications of ethofumesate. The mechanical control using two settings of the Koro Fieldtopmaker also proved effective, with a deeper treatment proving a more effective control than the shallower (fraise mowing) treatment, but with greater implications in terms of pitch reinstatement.