Key Tasks for July
General Maintenance
With the long daylight hours and warm temperatures, grass growth will be quite prolific if there is plenty of moisture about.
- Continue to carry out routine maintenance tasks, mowing, verticutting, fertilising, watering to keep the green in a playable condition.
- Grass growth will dictate mowing frequencies, in most cases clubs are cutting daily or on a three to four times a week regime.
- Only apply fertilisers if you have significant moisture in the green; clubs that are struggling to water should refrain from applying feeds whilst the greens are dry.
- Try and keep a diary of what work you have undertaken on your green, and keep records of how it has performed; take some pictures of the green and make note of any issues/problems you have.
- Get into the habit of taking a number of soil core samples to monitor what's happening underground; a visual look at a soil profile will enable you to monitor thatch content, moisture levels and root depth.
Mowing. With regard to mowing, ensure your mower is kept sharp and set at the correct height. No two greens are the same; Height of cut (HOC) will vary from green to green, with HOC influenced by several factors, type of mower used, condition of the green, sward composition and surface levels. In general, HOC will range between 3mm-8mm during the growing season, with most clubs cutting at around 5mm.
Some clubs will reduce their mowing heights, 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 topdressings to maintain levels.
Irrigation. Nowadays, irrigation is an important and integral part of the turf grass management industry, especially as the demand for better quality playing surfaces has increased. Therefore, careful consideration and investment in a decent watering system is a key requirement to managing fine turf surfaces. Irrigation is essential for a number of reasons:
- for plant survival and growth
- for soil formation
- for soil strength
- for chemical transport
- for managing playability
- for presentation
Water is influential in all chemical, physiological and biological processes of plant growth. The soil/plant water relationships is critical to the sustainability of any grass plant. Having an understanding of these relationships is critical.
All grass plants are a continuum of water movement. Over 90% of the plant's water requirements are transported through the plant from the soil profile, via the roots and stem tissues into the leaves and out into the atmosphere. Knowledge of these relationships is important when designing and operating irrigation systems. The main aim is to achieve a water balance within the soil profile ensuring that the grass plant is able to access available water from the soil.
Irrigation scheduling by the water balance approach is based on estimating the soil water content. In the field, daily evapotranspiration (ET) amounts are withdrawn from storage in the soil profile. Any rainfall or irrigation are added to storage. Should the water balance calculations project soil water to drop below some minimum level, irrigation is indicated. Weather forecasts enable prediction of ET rates and projection of soil water balance to indicate whether irrigation is needed in the near future.
It is also important to state that overwatering 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. Providing the green is adequately irrigated, 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.
Topdressing is usually carried out in spring and autumn in conjunction with the renovation programmes. However, some bowling clubs have a policy of applying topdressing materials during the season. It is important that an appropriate 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.
Rink Ends
This is often a contentious point between groundsmen and players.
Many players and committees insist on keeping the ends in the same position and direction, usually for obscure reasons such as "it's my lucky rink".
Playing in the same direction with the rink ends in the same position will cause uneven wear on what should be a flat, level green. Ruts and depressions will occur, causing the bowl not to roll true.
The rink settings should be moved laterally and directionally every 3 days or so, playing across and up and down the green.
On the same basis, all rinks should be used in rotation so that wear is evenly spread across the green. Just using the centre links will quickly affect the level of the green.
As we approach the halfway point of the year, we can hopefully afford ourselves a brief moment to look back at the past six months and reflect on the accomplishments and challenges we have overcome. Although June has provided some excellent warm weather, which has meant we have been able to enjoy being outdoors, it doesn't necessarily follow that it has been good for managing turf. Needless to say, when you look back and review the role the weather has played in managing turf so far this year, it hasn't been easy. Evenings and mornings were cold right up to the end of May, which has affected growth, alongside the lack of rainfall we have experienced. The typical UK average rainfall for June is 77.2mm; up to writing this report, the current UK average was 34mm. Coming out of that low growth period in May, coupled with the reduced rainfall, has led to challenging conditions for turf managers. Looking back at last year's report, it was a similar story; when we reached the 25th June, the monthly average only just went above 10mm!
Looking ahead to July, there is little sign of what will now be, for many, much needed rainfall. Where rain is forecast, it doesn't appear it will be anything substantial enough to make a significant impact. Of course, where irrigation systems are in place, these can be deployed to reinstate the moisture that has been lost through the day, but where these are not available, managing drought conditions may become a major priority. Where irrigation is available, managing the resource effectively to adhere to extraction licenses etc. will continue to be important. Daily temperatures look set to be around average for July, with 29 days at 18°C or above. Notably, there aren't many days forecast above 24°C, which may be important for those who are regularly managing anthracnose disease outbreaks.
Water management
Water management is a key tool for maximising overall plant health, even more so in periods of prolonged dry weather as those we are currently experiencing. It is important to ensure there is enough moisture to support nutrient uptake and growth whilst trying not to over apply to areas of turf where more is not required. Moisture meters are an excellent tool, particularly in these situations, as they provide factual data as opposed to a visual interpretation which is variable from person to person. Guidelines can be set for optimal readings and selective or hand watering can be implemented to only irrigate those areas where there is a requirement, thereby reducing over-watering the plant and reducing overall water usage. Wetting agents are useful for managing water and ensuring it enters to soil profile, where it is needed. Regular aeration, using a variety of tine depths, also helps to maintain pathways for water to enter the rootzone and pass through it.
Biostimulants
Applications of seaweed will elicit important beneficial defensive and stress responses in the plant and associated micro-organisms when applied at times of turf stress. Ascophyllum nodosum is a good seaweed source as it has to deal with tidal stresses. Half its life is spent under water and half its life out of water. Amino acids also play an important role in abiotic stress tolerance, helping plants to prepare for and cope with additional stresses such as varying changes in temperature and volumetric water content. They are also excellent at ensuring nutrients get into the plant, therefore, through dry periods where every part counts, they can be a useful addition to tank mixes to ensure efficient uptake of products. Calcium and Potassium are both key nutrients when considering biotic and abiotic stress due to their role in cell walls and water regulation. Therefore, look out for these when selecting your fertiliser.
Disease
For Anthracnose (Colletotrichum cereale), warm, humid weather and increased light intensity are the primary environmental factors controlling the development of conidia. Laboratory studies indicate that Colletotrichum cereale produces conidia at temperatures between 24‑32°C, with increased maturity of conidia observed at 28°C compared with lower temperatures. Once conidia have been excreted from the acervuli in a water‑soluble matrix, they can be spread by wind, water or human activity, but need continued leaf surface moisture to establish. Little and often applications of nitrogen have been shown to mitigate the development of the disease and helps to minimise any stress on the plant. Applied preventatively fungicides are available as a method of control, although some will find the above measures sufficient when dealing with this disease.
Pests
Emergency authorisation for Acelepryn has been issued for the treatment of chafer grubs only. The purchase window for chafer grubs expires on 28th August and the storage and application window ends on the 28th September 2022.
A separate authorisation is awaiting approval for Leatherjackets, but this is yet to be approved. As with previous years, all applications must be approved by a BASIS qualified advisor, who has had the relevant product training.
For anyone not able to apply Acelepryn, cultural and biological controls, in the form of Entomopathogenic nematodes, are the only legally authorised controls available. For best results, ensure you follow applications guidelines.
Tom Wood
B.Sc (Hons) | BASIS | FACTS
- Keep machines overhauled and clean.
- Inspect and repair any watering or irrigation systems.
- Continue to check and service your floodlighting systems.
- Replace any worn tines on your aeration equipment.
For all your training requirements, please contact our preferred training provider - Grounds Training.
Visit the website: Groundstraining.com or email info@groundstraining.com