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Courtesy of National Club Golfer


Have the greens at your club just been dug up and if so why?

You wait all winter, all spring and then half of the summer to get some decent putting.
Gradually, confidence build and you find stroking your putts and be ball rolling smoothly its target. Bliss - your touch improves, the three-footers taxing and a few longer ones even starting to end up in the bottom of the cup.
Then, the next thing you know, you turn up for a few holes of practice on a nice evening only to find diggers  parked by the greens dreaded process of hollow tining underway.
Cue putts bouncing along their way and short putts turning sideway’s whenever they get within a foot of the hole. It’s enough to drive us dedicated golfers round the twist. Some of us - shameful to confess - have even been known to consider taking the name of those hardworking greenkeepers in vain.
Yet strangely enough, the nation's greenkeepers do not embark on this process just to annoy us golfers (or at least only a few of them do, at any rate).
In this, the second instalment of our new series of features on greenkeeping, we thought it was about time we gave the experts the chance to explain all.

So we asked Steve Robinson, head greenkeeper of the 1929 Ryder Cup venue, Moortown, in Leeds, if he fancied the chance to respond on behalf of greenkeepers up and down the country.
Moortown, a classy combination of parkland, moorland and heathland, began their latest batch of hollow timing in the first week of August, so Steve was ideally placed to answer our questions.

In layman's terms, what is hollow tining and why is it needed?

SR: Hollow timing is one form of aeration. By removing numerous cores from turf we are increasing the percentage of air in the soil which is needed by the grass roots. It also allows the release of unwanted gases like carbon dioxide. The increase in air spaces in soil also helps to relieve compaction which is another problem when trying to grow quality turf. One other major advantage is that the hollow tining process removes thatch from the upper soil profile.

How many times per year does it need doing?

The intensity of any form of hollow coring all depends on what the club is trying to achieve. Is there a thatch problem, are the greens compacted and not draining well after rain or do we need to remove undesirable soil and replace with a sand top dressing?

When do Moortown hollow tine and to what extent does this depend on the weather?

We do not have any strict regime when we do severe work to the greens; it all depends on the club diary and when disruption is acceptable. So the maintenance week is decided very early on in the year so the weather for any particular week chosen can be problematic.

It seems different clubs and greenkeepers have different ideas on when to hollow tine. Can you explain why?

If you ask most greenkeepers when the best time to do this kind of work they would probably say May to August, as this is when growing conditions are at the best and so any recovery will be quickest. Unfortunately this is the main playing season so disruption during this time is undesirable.

It seems there is a trend to hollow tine earlier and earlier - in the late summer rather than the autumn. Why is this and what are the pros and cons?

Some clubs will complete the work much earlier in the season or even towards the end. This way golfers' expectations are lessened due to the weather and time of year so any disruption is more acceptable, particularly if the recovery takes longer due to the lack of growth.

When conducted in, say, September after a bad summer, can you understand why golfers get upset that perfect surfaces are being dug up?

Complaints from golfers following maintenance weeks are always unfortunate. I don't think this will ever go away at any club. It puts more importance on knowing your own particular problems with your greens, choosing the best methods to reduce the problem and put particular importance on the timings of work to suit your club.

How long does it typically take for greens to recover?

The recovery of the greens after this kind of work varies depending on the size of tines and the spacing between them (how much surface area you are trying to impact upon) and obviously the weather conditions following the work. Ideally this would be mild with adequate rainfall rather than too cold or too hot or too dry.

What about top-dressing. Is this essential or optional?

Top dressing is the process of applying a sand/soil to the surface to fill in the holes made by hollow lining. Ideally you would try to completely fill the holes but, if you have done the work outside of the growing season and the grass is not growing, sometimes it is not possible to apply large amounts of sand for fear of smothering the turf.