Leafspot divides opinion!

"When, three weeks later, the disease reappeared and we had to spray again, you would have thought World War III had broken out"

Whatever your business or trade, there is always something that crops up that you have never seen, and groundsmanship is no different.

We had this experience during the autumn when something called leaf spot appeared on our stadium pitch, just weeks after a major renovation.

None of us had seen this before, but noticed a brownish area in one of the goalmouths one morning prior to cutting the pitch. We put the brown patch down to someone messing about on the pitch, perhaps a couple of cheeky players having a kick in on the new surface late the previous day after we had gone home.

We cut the pitch that morning but, after lunch, noticed the brown area in the goalmouth had developed further, whilst another area had appeared just outside the centre circle. It was then we knew something was not quite right and called in the experts who told us it was definitely leaf spot.

The fungi that causes leaf spot directly penetrates leaf sheaths and blades at random, or enters via mowing wounds, which commonly leads to tip blight. Both our stadium mowers had been fully serviced prior to the renovation, which included new bottom blades and regrind, so we knew that mowing wounds were at a minimum.

We were told that, when turf grass is succulent from recent nitrogen fertilisation, and there is abundant moisture on the leaf blades, numerous leaf spot infections per blade can occur.

Well, we had extensively fertilised the pitch following the renovation, and we all know what a wet summer and autumn we had. The leaf spot may then coalesce and cause extensive blighting. The fungus may even invade the crowns and roots, leaving the plants weakened and rotted. This severe stage is called "melting-out." Large areas of dead or badly weakened grass may result. Thankfully, we acted with a fungicide spray before the disease took hold and, within a week, the pitch looked as though nothing had affected it.

Of course, the suits that control the purse strings at the club had a major whinge over the groundstaff spending another grand. So when, three weeks later, the disease reappeared and we had to spray again, you would have thought World War III had broken out.

We spent several hours trying to educate them, using our recently acquired knowledge of leaf spot, and the reasons why it had returned. But, to them, the first fungicide spray had not worked and the company that supplied it should be held responsible! Imagine their reaction when we quoted several local Premier and Championship teams that repeated spraying every 5-10 days (depending on rainfall and mowing frequency), not only on the stadium pitch but also at their training grounds. Yet, as far as they were concerned, the fact the pitch had been sprayed, meant that leaf spot should never be seen again in their lifetime!

We had probably never seen the disease at our stadium before due to the fact that it is very open and the grass dries very quickly, plus there is excellent airflow through all four open corners.

We will certainly be looking to re-seed with a mixture of resistant cultivars of different turf grass species. The genetic variation of such a mixture should reduce the chance of major damage in the future.

The fact that we cut the pitch the first morning we saw evidence of leaf spot was the worst thing we could have done, as this definitely helped spread the disease.

We have also changed our way of irrigating the stadium pitch to try and keep the leaf blades dry for as long as possible. We try not to water in the late afternoon or early evening and avoid frequent light sprinklings.

Mowing frequently and only cutting one third of the grass blade at a time is another way of prevention, as is not mowing when the grass is wet; not always possible, I know!

A nice clean cut with a well maintained mower also helps, but to a good groundsman this is standard procedure.

I would say we are well up to speed with leaf spot now and know what to do to prevent or lessen the chance of getting an infection. It just goes to show you are never too old to learn.

Keep the faith; and keep cutting the grass, after all that's all you do.