July Bowls Diary
By Laurence Gale MSc
The warm dry weather at the beginning of this month will have certainly provoked the use of automatic or static sprinkler watering systems, however not every club has the luxury of having their own system and remain reliant on the weather or using some hand held watering equipment if pressure allows.That is why you see many greens beginning to turn a lovely golden brown colour.
However, the long term affect of drying greens could be detrimental to surface playability. The surface could begin to break up, particularly on sand predominant greens. Sand becomes unstable when in a dry state. Also the surface will become bumpy, different grass species will respond differently under drought conditions, growth rates will change depending on habit and root structure, thus promoting an uneven surface. Once the soil goes beyond a certain drying stage you are likely to encounter dry patch symptoms, whereby the soil becomes hydrophobic, being unable to absorb water. The water simply runs off instead of soaking into the soil profile.
Water will also always wash off from the high spots into the low areas, so the low spots tend to remain green and lush. This variation of dry and wet areas will affect surface playability, the bowls will fly across the dry areas and slow down on the lush green areas.
To reduce plant stress it will be necessary to raise the height of cut, most clubs will be mowing at a height of between 4-8mm. Raising the height by just 1mm will significantly help the plant recover during dry periods. It may also pay to vary the way you turn the mower on the edges of the green. Turning on the same spot will increase wear and tear. One way to spread the weight of the mower is to use a board for turning on, it will reduce compaction and constant wear that you constantly see on the edge of many greens.
It would also be wise to refrain from any grooming, scarification and verticutting practices during dry periods; it adds to the plant's stress which, in turn, will cause it to weaken, be susceptible to disease and even die.
The use of wetting agents are a good preventative cure for dry patch. Many Greenkeepers and Groundsmen are now using these products regularly on fine turf situations. Wetting agents are usually applied on a monthly basis.
It is also important to state that over watering can equally be damaging to your surface. Keeping the surface waterlogged will reduce air porosity and decline plant growth, constant shallow watering will also increase Poa annua populations. Ideally, you should apply a sufficient amount of water to flood up the green and then allow to drain for two - three days. This allows the water to get deeper into the soil profile.
Aeration is a key activity to ensure that there is a good air/gas exchange going on in the soil profile. The use of a sarrel roller (depth 5mm) helps keep the surface open without disturbing the playing surface. Deeper aeration should only be done with micro tines when conditions allow as we do not want to risk disturbing the surface especially during the playing season.
Brushing/switching of the playing surface keeps the green clean and removes any dew or surface water. Keeping the surface dry will aid resistance to disease.
Fertiliser treatment and turf tonics can be continued in accordance with your annual programme. If you haven't got a fertiliser programme, have your soil tested; try an independent soil analysis company for an impartial set of results.
Most grounds staff will be applying a summer N P K fertiliser, perhaps something like a 8/0/6 reducing the N and P inputs trying to maintain a stable balanced growth during July. The choice of material and how well it works will be dependant on factors such as soil type and weather, with moisture and air temperature being the catalyst for growth.
Most fine turf mowers have cassette fitting attachments that offer additional maintenance operations such as grooming and verticutting. These are both operations that need good growing conditions, and effectively remove thatch and side shoot growth enabling the promotion of an upright plant and denser turf growth.
To help prevent constant wear in the same areas it is important to move markers and rinks on flat greens. Mowing frequency will often be dependant on the resources available to the clubs. Ideally, most clubs will be mowing daily or at least three times a week. Regular mowing will be required to maintain sward height at around 4-8mm.
Some clubs will reduce their mowing heights further, perhaps down to 3mm to help speed up the greens for club competitions. Prolonged mowing at these heights will lead to plant stress. As an alternative, instead of reducing the height, do a double cut (in different directions), this will speed up the greens without reducing the grass height. The speed of greens can be affected by other factors - too much thatch is the main cause of slow greens, or the fact that the greens have not had enough top dressings to maintain levels.
Keep an eye on fungal disease attack and use approved fungicides to treat infected areas. Fusarium can be very prominent at this time of the season. Ensure the greens are kept well fertilised, preventing the onset of disease.
It is important that you use a compatible rootzone material for any repairs. These come in different blends, a 70/30 sand soil mix is the one commonly used by most groundstaff, who usually mix in their grass seed prior to spreading and integrate it into the worn areas.
Seeding sparse or bare areas can be continued. Any rise in soil or air temperatures will help germination. Use germination sheets to aid this process but remove the sheets regularly to check for disease. Remember that without good seed to soil contact the operation is useless. Ensure you use new seed as old material may not give you the required germination rates.
Top dressing is usually carried out in spring and autumn in conjunction with the renovation programmes. However, some bowling clubs have a policy of applying top dressing materials during the season. It is important an appropriate top dressing material is sourced to ensure compatibility with the existing rootzone materials of your green. The last thing you want to encourage are rootbreaks in the green. Spreading of the materials can be achieved by several methods, utilising pedestrian or ride on disc or drop action top spreaders, or by hand using a shovel and a barrow. It is important to get an even spread of material, the aim is to put on a very light dressing, followed by brushing in with a lute or drag brush/mat to restore levels.
Inspect and clean out drain outfalls and gullies. Replace and level up drainage ditch materials.