The Circle of Decline in Golf Greens
The diagram below shows the process that many poorly maintained golf greens experience over a period of years if commonly accepted maintenance regimes are followed blindly.
Modern greenkeeping methods tend to ignore the complex eco system that exists in golf greens between the soil, turf and many other organisms such as michorizzal fungi and soil microbial life.
Instead the trend continues to be towards inert, high sand rootzones and an endless round of expensive symptoms management involving chemical fertilisers and pesticides, which many clubs are now suffering the consequences of.
The common result of this failure to address the needs of these turf/soil eco-systems properly is that greens spiral into what I have called the Circle of Decline.
Simply put this is the devastating course of events that go on largely un-noticed by many golf clubs until it is too late to effect a quick recovery.
A lack of attention to thatch build up results in a thick mat of un-decomposed dead grass shoots, roots and leaves. This mat gradually effects the turf’s ability to put down roots and take up water and nutrients. In advanced cases a root break will occur and Localised Dry Patch is a very common symptom of excessive thatch also.
Disease
In winter, thatch can hold water like a sponge and encourage fungal diseases such as fusarium patch to take hold. This sometimes results in over use of chemical fungicides which kill off the disease and many beneficial fungi into the bargain.
Symbiosis
Grass plant roots can draw moisture and nutrients from only 1 to 3% of the soil medium around them and so rely heavily on beneficial fungi to make best use of the available soil nutrition. If this symbiotic relationship is broken, your turf begins to have difficulty obtaining the necessary nutrition from the soil.
This often results in over fertilisation, as much of what is applied is not made available to the plants due to the anaerobic conditions which now prevail. The natural release of plant nutrition usually provided by soil micro-organisms working on organic material is compromised so plants struggle to get all of the nutrition they need and thatch builds up quickly.
By now conditions are highly favourable to the weed annual meadow grass which is a very shallow rooting species. The finer fescue and bent grasses are compromised and in an effort to keep the meadow grass alive excessive irrigation is required.
This contributes even further to the excessive thatch layer as meadow grass is a prolific producer of thatch and we are back to the beginning of the cycle.
The continued insistence on adding tonnes of sand to greens year in year out, only makes this problem worse and it is important for clubs to start to realise the damage that their maintenance practices are causing.