Bowling Green Scarification & Verticutting

Scarification and verticutting will help to prevent much of a thatch build-up and will also keep the surface layer open and free from decaying organic matter of cut leaves and plant sheaths.
Verticutting focuses on the surface, whilst scarification focuses on penetrating into the surface layer.

Regular light to medium depth scarification (3mm-5mm depth, with the latter leaving score marks on a surface, but which should rapidly colonise over) is more appropriate than deep and aggressive scarification, which will typically cause some surface disturbance and can also start to defoliate the surface to an unacceptable degree. If the surface disturbance is unacceptable during or after the use of a scarifier then this would indicate that the depth (i.e. severity) of scarification is inappropriate and a reduced depth of penetration will need to be applied.

Adjust the depth setting accordingly: a small area which has been scarified deeper than desired is not necessarily going to prove a problem, so long as adjustments are made as soon as possible. If conditions allow for a slightly deeper setting than anticipated and it is suitable to go a bit deeper, then why not do it? This illustrates the need to be vigilant in turf maintenance activities and adjust machines according to the prevailing conditions and not to stick with fixed settings but to adapt intelligently to the situation in hand.

The actual depth setting used will depend not just on the time of year, bearing in mind that the grass plant does need to recover from this activity fairly quickly, without unsightly score marks being left on the green for any length of time, but also the condition of the sward and surface layer.
During the main playing season surface disturbance will want to be kept to a minimum, so light to medium depth only, followed by a mowing afterwards to keep the surface clean. Scarifying late in the autumn can weaken the sward, leaving scars present throughout the entire winter.

Grooves made by scarification should be rapidly recolonised by existing desirable grasses. If grooves remain then this is a sign that the sward is under stress and the exposed areas will be more readily invaded by annual meadow grass and weeds. Only scarify when the grass is growing strongly and able to speedily recover from the actions of the blades. April to September are typically the main periods for scarification, except when prolonged dry spells are present, with March and October scarification being acceptable when conditions allow.
Scarifying in various directions will be beneficial – in the line of play to diagonal. Usually, the next scarifying activity will be slightly off angle to the previous one (about 10° or so), but not at right angles, as undesirable cut squares might start to appear in the sward, especially during dry sunny weather.

The frequency of these activities might be based on scarification on a fortnightly to monthly basis during the main growing season, with verticutting on a weekly to fortnightly basis, interspersed between the scarification. Where dry/drought conditions or cold spells arise then these activities would be reduced or temporarily stopped.

If the green has been renovated in spring, then be careful not to scarify nor verticut after renovation until the grass seed has become adequately established to be able to withstand the actions of the equipment. Verticut and scarify before the seeding and topdressing as part of the preparation work. Following adequate establishment, these activities should only be carried out on a light setting to start with and gradually building up to, at most, a medium setting during the playing season. There is little point scarifying or verticutting and tearing out newly germinated seed before they are established.

Try not to confuse scarification with verticutting because the density of blades on a verticutter is higher than that of a scarifier and severe damage can be caused to a green surface if a verticutter is incorrectly set.