Key Tasks for August
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.
Many bowlers complain about slow, inconsistent greens, often resulting in clubs trying to speed them up by shaving off more grass. In the short term, this may increase speed but, in the long term, it will be very damaging to the green.
- Remove and control the rate of unwanted vegetative growth (thatch and side growth) by regular grooming and verticutting operations.
- Light applications of topdressing will restore and maintain surface levels, thus increasing green speed.
- Mowing in several directions to reduce nap layering will help increase green speed.
- Double cutting for matches will increase green speed.
- Controlling soil moisture will help influence green speed.
- Brushing/switching of the playing surface keeps the green clean and removes any dew or surface water. Keeping the surface dry will improve resistance to disease.
Mowing. Too many bowls clubs choose to cut their greens far too low during the summer months, mainly influenced by club members who want faster greens. Do not be tempted to cut below 4mm unless you have the expertise, resources and knowledge to support this type of maintenance regime. Mowing the green below 4mm will, in the short term, give the members what they want - fast greens - however, there is often a cost to bear for doing this. It generally comes in the form of the green suffering in many ways, grass cover begins to thin out, bare areas develop which allow weeds and mosses to establish. Beneath the surface, the constant rolling will have compacted the soil profile, reducing the air spaces. This leads to poorer root growth, less movement of water and resulting in flooded surfaces.
In fact, the most common cause of slow bowling greens is the presence of a layer of accumulated organic fibre, commonly known as thatch. This is found just below the surface and is caused by the accumulation of matted grass stems. This is easily detectable when you walk across the green and the surface feels soft.
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 sarel roller (depth 5mm) helps to keep the surface open without disturbing the playing surface. Deeper aeration should only be done with micro tines when moist conditions allow penetration.
Irrigation. 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.
The soil water balance will be affected by a number of factors:
- Soil type and condition; the water holding capacity of soils will vary depending on their classification. Clay soils can hold more water than loamy or sandy soils, therefore soil type will effect and contribute to the amount of water required. Soils are continually going through phases of wetting and drying caused by local weather conditions.
- Turf type and condition; healthy vigorous turf will transpire more water than an unhealthy turf plant.
- Time of the year; there is likely to be more soil water present during the spring, autumn and winter months when temperatures are cooler coupled with higher levels of rainfall.
- Weather; air temperature, daylight hours, solar energy inputs, wind speed and shading are factors that will affect evapotranspiration rates.
- Maintenance regimes; keeping the soil open and aerated will increase the drainage capacity of the soil. On the other hand compacted soils will prevent the movement of water through soils, often creating an environment that prevents water getting down into the soil profile. By carrying out effective regular maintenance regimes that include aeration, scarifying, harrowing, brushing, top dressing all help to keep the soil in good condition.
- Irrigation system; type, capacity, running time, calibration and efficiency.
- Water resources; quantity and quality. The quantity of water available, and the amount licensed for use in any one year, will determine the performance of any system and irrigation capabilities.
- Facility type; design and construction.
- Greenkeeper knowledge; it is important that there is someone who understands all of the above parameters and can access the water requirements of the turf and correctly implement the right irrigation schedule for the facility.
Soil water relationships are key drivers in maintaining plant health, so it is vitally important you readily water your bowling green and ensure the plant does not become stressed from the lack of water, on the other hand you do not want to be over watering, as this may bring you other problems.
Fertilising. 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.
A regular feeding programme is essential to maintain colour, vigour and well-being of the sward. A combination of a slow release granular based fertiliser, topped up with some organics/liquid feeds, are becoming a popular method of feeding bowling greens. The slow release will generally last around three months, whilst the liquids can be applied every 4-6 weeks depending on the plant's needs.
The use of wetting agents are a good preventative cure for dry patch. Many groundsmen are now using these products regularly on fine turf situations. Wetting agents are usually applied on a monthly basis.
Soil wetting agents are available in three forms - Residual, Penetrant and Curative.
Residuals keep working over a given stated period, depending on the amount of time you require it to work they hold water near the surface.
Curatives combat the problem of dry patch by stripping off the waxy organic coating on the soil particle which renders the soil profile water repellent, but never totally alleviates the problem as, every time you topdress with sand, you add a further layer of water repellent organic coating to your soil profile. This type of wetting agent is believed by some to also remove beneficial bacteria etc from the soil and therefore can be controversial. One of the lesser known facts is that when using curatives your water consumption can reduce by up to 30% year on year. Product example Correct Oars by Vitax.
Penetrants help remove standing water as well as move water through the profile. Many turf managers use penetrants in a tank mix, when using other chemicals to get the product through the profile immediately.
To achieve the best from wetting agents any factors contributing to the dry patch should be addressed. Such as alleviation of compaction, removal of thatch and preventing the rootzone from reaching the critical moisture content by ensuring even and timely irrigation.
Best results are achieved by applying wetting agents in a programmed approach, starting early in the season before symptoms are observed. Blanket applications are also more effective than spot treatments.
Generally, you should be looking at a programme of scarifying in several directions to remove unwanted thatch layers and dead matter, aerating with some deep solid tines to break up compaction, topdressing with some 70-30 topdressing to restore levels, and overseeding with some new grass seed.
Unfortunately, one of the deciding factors that often reduces the effectiveness of these planned works is the amount of money the club has available. It can cost anything between £1200-£1500 for a contractor to come in and do all the work. Savings can be made if the club undertake the work themselves, however, the effectiveness of the work carried out will be determined by the equipment they have at their disposal.
Savings can also be made if clubs buy materials in bulk (several clubs group buying).
Full details of bowls green maintenance regimes and renovations are available with our Online Bowls Green Maintenance Course
After many weeks of unbroken sunshine across the country turf surfaces in all regions have suffered from abiotic stress brought about by heat and drought. As we enter in to August the first vestiges of recovery following localised rain fall are in some areas, beginning to show through. However we are not yet out of this period of stress and dormant turf surfaces and back to business as usual. Grass of course goes into either partial or complete dormancy when subjected to water stress in an effort to conserve the vital crown and roots. Once the weather does break the plant will restart leaf production and swards will return, however turf managers should consider what is returning and how useful those returning species are. Moss and Poa annua will be quick to take advantage of a situation they are evolved to excel in. It is very much the case that the quality of surfaces in 2019 will be dictated by the quality of the autumn renovation in 2018.
Soil which is baked hard will be hydrophobic meaning that early post drought rain fall will not be fully optimised. A penetrant wetting agent will break the surface tension meaning that more of the water which does fall is able to effectively soak into the soil where it is needed to drive fast and efficient recovery. Multi action wetting agents which combine a penetrant with the retention properties of a block copolymer will hold and suspend water which does penetrate into the soil at a depth where plant roots can access it.
Once growth does return regenerating a sward in as short a period of time will maintain surface integrity and stability. Turf managers would be wise to minimise high nitrogen inputs at this time, opting instead for a gentle all round feed which includes secondary macronutrients and micro nutrients with a moderate quantity of nitrogen and phosphorus. It is worth considering that calcium availability becomes limited in dry soils, calcium of course being a driver of cell division and growth throughout all regions of the plant.
Ideally initial feeds would consist of a foliar liquid application to reduce the risk of scorch if soils are still relatively dry. Foliar feeds are also absorbed directly into the plant via leaf absorption. This will encourage steady consistent recovery without forcing excessive growth in September as dew's start to get heavy. Partnering a feed with the restorative powers of plant phytohormones in seaweed bolstered by the energy source of carbon sugars will underpin the plant soil ecosystem. Humic acid acts to facilitate enhanced nutrient absorption into the roots via the soil water solution pathway, so utilising this ability once soil water levels are returning will help to make nutrition in the soil readily available.
Allowing the soil to breath via aeration is a cornerstone of turf management practices throughout the year. Where surfaces are hard then sarel tine aeration will help to increase the surface area as well as break capping, both of which will facilitate improved penetration of irrigation and rainfall. Areas where soils begin to rehydrate and soften will benefit from deeper aeration with solid tines. This will allow accumulated gasses to escape.
Renovation Considerations - Scarification, Overseeding and Topdressing
If conditions remain dry then aggressive maintenance operations will have to wait until strong and consistent recovery growth returns. However following prolonged dry weather the renovation practices of previous years will not necessarily be adequate and due consideration ahead of time needs to be factored into club meetings and budgets.
The main consideration should be that areas which do not recover well post drought will need to be seeded and baked organic matter will need to be broken up. The survival rate of grass seed which germinates within a thatch layer is significantly reduced compared to seed which germinates in contact with the soil. Aggressive scarification of surface organic matter opens up spaces for seeds to contact the soil as well as allowing water and oxygen to better penetrate into the soil.
Where recovery is patchy or slow providing an adequate supply of seed from desirable species will be important to keep surfaces clean. If there is space in the profile weeds, Poa annua and moss will fill them first ahead of the desirable perennial grasses. Overseeding rates may well need to be increased to compensate for dead and slowly recovering desirable species. Sown seed requires protection, to maximise germination, as a result establishment rates for uncovered grass seed on the surface are significantly reduced.
Once scarification and seeding has been completed top dressing introduces vital mineral matter into the surface thereby diluting dead organic matter and thatch with mineral material. This mineral matter harbours moisture and nutrients as well as creating pores for air. All of which help microorganisms to decompose organic material.
Grass seed requires a light covering of mineral matter to promote effective germination and establishment. Application of top dressing compatible with the underlying soil surface is important. A medium to heavy dressing in during the autumn renovation helps to protect seedlings and return surface levels post scarification and aeration.
Once moisture returns so does relative humidity, when humidity combines with stressed turf and warm temperatures, conditions are conducive to the growth of fungi. Consequently a host of turf diseases can expect to be witnessed through August and into September.
However 2018 is the first year without the curative activity of the fungicide iprodione, the active ingredient in Chipco and Interface. The only chemical options for turf disease are preventative systemic substances. Application prior to the observation of symptoms is vital in ensuring their success.
Diseases to be on guard for during August if conditions become increasingly warm and wet include; Anthracnose, Dollar Spot, Brown Patch, Rusts, Red Thread, Leaf Spot.
It is worth consulting the Turf Disease Triangle below and giving due consideration to what circumstances, conditions, maintenance practices and inputs on your site may influence each of the three factors.
Away from Plant Protection Products such as fungicides, which directly target a virulent pathogen, thriving in a favourable environment. One of the most effective tactics available to the turf manager is to reducing the susceptibility of the host. In this regard, adequate water availability combined with appropriate and balanced base nutrition are further bolstered by the benefits of cell wall boosting and plant system enhancing calcium, phosphite and silicon.
August is the start of the Entomopathogenic nematode application window for the control of Chafer grubs and Leatherjackets. Be sure to apply when soil moisture levels are adequate and where levels can be maintained with irrigation in the absence of rain for best results
- 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.
We are pleased to announce the launch of our new Grounds Training website, together with our new suite of online courses.
Our Lantra Accredited Bowls Green Maintenance Course is now available as an online course.
Now you can learn about maintaining a bowls green in the comfort of your own home and in your own time. This newly developed course consists of a number of videos with assessment questions, and an accompanying hard copy course manual. The online course is Lantra accredited and provides you with all the basic knowledge required to maintain a green over a 12 month period.
Grounds training is the only provider of LANTRA accredited training courses in the maintenance of bowls greens.
We can also arrange Lantra accredited training on site to groups of 6 - 10 people. Email Carol Smith for information.
The Course Manual is available for purchase separately.