Bowling Green Maintenance: 25. Weeds

Weeds on a bowling green can detract from the production of a very fine uniform surface.

Small weeds such as clover/trefoils, pearlwort, yarrow, have been called the “Troublesome Trio” (Sutton, M.A.F. (1962) ‘Lawns and Sports Grounds’, pp105-109) and can be routinely weakened and reduced by scarification and verticutting. Parsley piert is another fine weed that can be troublesome on a bowling green.

Where selective herbicide is to be applied then it should be when the grass plant and weeds are growing strongly: typically, this will be during May to early June on established swards, and the minimum period stated on the herbicide label for newly sown turf, which might typically be at least 2-months, in which case June might be the earliest time. Ideally though, for a fine turf surface such as a bowling green, which isn’t a huge expanse of turf, the use of a herbicide should be minimised due to effective cultural and physical practices being routinely carried out.

Broader type weeds, such as daisy, self-heal, plantains and dandelions, may germinate and start to develop as juvenile plants, but they should never be allowed to develop into a mature plant which will smother the adjacent grass as it matures. There should be no need to apply a selective herbicide to a bowling green for these larger types of weeds because they should have been hand weeded at the juvenile stage.

Moss is probably the most troublesome weed (because it is an undesirable plant for this situation) on bowling greens and will always be present to some degree. The aim is to create conditions which are less desirable for its development and to increase the competitiveness of the desirable grass species to reduce its potential for encroachment.

Periodic applications of sulphate of iron during autumn to late winter or early spring, for example, in October, November/December and February, combined with good working practices throughout the year of not cutting the green too short, keeping the surface well aerated, preventing a build-up of thatch, not over-watering, not over fertilising and spreading wear over the entire green will help to improve the competitiveness of the grass at the expense of moss.

Yorkshire fog (Holcus lanatus) is a weed grass, appearing as coarse leaved, lighter green patches within a bowling green, which can be difficult to control. Scarification and verticutting can help weaken this grass, but often it will need to be cut out and physically removed to eliminate it totally. This would only really be done if it was present on premium quality greens or if the patches were causing significant impact on play or particular concerns over the visual appearance of a green.