Greens Renovation Info
With our biennial greens renovation fast approaching I thought I would answer some common questions we receive by players at this time of year.
Without getting technical, there are a number of reasons why we renovate the greens, to relieve compaction, to get air into the profile, reduce any thatch build up and to add soil amendments when the greens are open from coring. To be blunt if we didn’t, the greens would deteriorate in condition and eventually die. Further explanations follow.
Why Core ?
Like so many things, the quality of a good putting green is more than skin deep. In fact, the condition of a green has a lot to do with what goes on below the surface. In order to keep grass growing at 3mm you have to have deep, healthy roots. Good roots demand oxygen. In good soil, they get the oxygen from tiny pockets of air trapped between soil and sand particles.
Over time, the traffic from golfers' feet (as well as heavy mowing equipment) tends to compact the soil under the putting green. When soil becomes compacted, the air pockets on which the roots depend are crushed, and the roots are essentially left gasping for air. Without oxygen, the grass plants will wither and die.
Is there any other reason ?
Yes another reason to renovate is for thatch. Thatch is the layer of dead, decaying matter between the green leaf and the soil, if left unchecked, the greens become spongy, soft and slow. The turf also suffers, as this layer acts like a sponge remaining constantly wet, water movement to the soil below is restricted and the roots of the turf tend to remain in the thatch layer. During warmer weather this leads to premature water stress as the thatch dries out sometimes with the turf dying completely. Excessive thatch also provides ideal conditions for Diseases and Pests to grow and spread.
We always used to pull the core out now we just punch holes with solid tines why?
The results from soil sampling show our greens have an organic matter content of just 0.5% where the recommended range is 3 to 5%, further testing also shows the movement of water through the green sand profile is between 5 and 10 times that of the recommended rate. This is a result of using native virgin sands to fill the core holes over a long period of time without adding amendments, effectively removing the limited humus in the greens and replacing it with coarse straight sand.
By using solid tines in conjunction with soil amendments we can speed up the process of increasing the organic matter content, micro organism activity and slowing the movement of water through the profile enough so that we still get good drainage and air pockets but without the premature wilting of turf through lack of moisture caused by excess drainage.
In saying that, we do need to be mindful of creating a layer of organic matter. As we are approaching a more manageable level we will be alternating the use of solid tines and Hallow tines set slightly deeper than the solids ( pulls the core out of the green) in future.
Adding of Soil Amendments – Each renovation period we conduct soil sampling, amendments to be applied are governed by the test results. We pay close attention to PH levels, Calcium and Magnesium levels, Potassium levels and minor nutrients. It is the most effective time to apply these amendments when the greens are open from Aeration. We also apply products which encourage beneficial micro organism activity.