May Bowls Diary 2020

Editorin Bowls
Expected weather for this month:

After April's hot spell, we can expect better growing conditions in May, with rainfall and temperatures around average for the month.

Key Tasks for May

With so much uncertainty around at the moment, and Government guidelines on how and when people can begin to participate in sport again still to be confirmed, we suggest you keep in contact with your respective sport's governing body for any up to date information.

If you have been given permission to continue to maintain your bowls green(s), then the following should help.

The emphasis at this time of the year will be on mowing frequency, as long as there is sufficient moisture within the soil

Mowing. Greens should be mown at least three times a week, with some grooming, verti-cutting or brushing being undertaken on a weekly or twice weekly cycle to improve air movement and reduce thatch levels building up in the sward profile.

The sward will be actively growing due to the increased soil temperatures, coupled with the stimulation of fertiliser applications. Regular mowing will be required to maintain sward height at around 4-5mm. Verti-cutting/grooming fortnightly can be carried out to help speed up the green and help improve the health of your turf.

Aeration should continue, using a mix of micro, needle or star tines which give maximum effect and almost zero turf disturbance.

Regular use of a sarrel roller will be beneficial and the use of micro tines to aerate the green will help reduce soil compaction, 'vent' the root-zone and to allow water to move quickly from the surface and into the root-zone, thus encouraging the turf to root deeper.

Irrigation: Soil and air temperatures usually increase in May, often bringing on the need to irrigate. If soil profiles, particularly sandy soils, are allowed to dry out too much they often become water repellent (hydrophobic), a state when soils can become difficult to re-wet. Often the first areas to suffer on greens particularly crown greens are the high spots on the green. You may need to spend more time hand watering these problem areas.

When you do water, ensure you go to a depth of 100-150mm to encourage the roots to go down to find the water.

May is a month when spring really bounces into full flourish, with fresh leaves on all of the trees, and many flowers coming into colourful bloom. The grass plant takes full advantage of longer days, warmer temperatures and available soil moisture by producing a large volume of leafy growth. In a naturalised situation, this is energy expended in advance of flowers and then seed later in the summer. In a sports turf situation, the plant is still responding to these cues and drives, but it is our intervention with a lawn mower which tames the growth into a lush sward, albeit with one species of note proving the exception, Poa annua.

The start of May often heralds the onset of Poa annua seed heads across surfaces, and a subsequent drop in aesthetics and playing performance as a consequence. Grooming allows for mechanical removal of the seed heads and is a tried and tested method for minimising the negative effect on play and performance during the annual window of Poa annua flowering.

May 2020, however, marks the first opportunity for UK turf managers to access and utilise the plant growth regulator - prohexadione-calcium. Prohexadione-calcium is a Class A late gibberellin inhibitor, a trait it shares with the long established and successful trinexapac-ethyl. With regard to Poa annua, prohexadione offers two advantages; it regulates Poa annua on a par with perennial species, this allows for greater consistence of growth regulation across surfaces over time. Secondly, it regulates the flowering potential of Poa annua, a trait which mitigates the negative consequences of this plant’s inflorescence upon both aesthetics and playing performance.

In normal circumstances, both those metrics would be primary areas of day to day concern. Of course, we presently remain in a situation outside of normal circumstances, therefore maintaining playing quality and aesthetics from the ingress of Poa annua flowers is likely to be on the lower end of priorities. That being said, prohexadione-calcium does represent an opportunity to capture two birds with one stone. First by regulating plant growth and thus easing pressure on mowers and staff alike, then as a secondary effect, the suppression of Poa annua flower head production; something which, by extension, reduces the number of seeds that subsequently form and then drop directly into playing surfaces. Over time and with complementary integrated maintenance principles, this will reduce the ability of Poa annua to regenerate in swards where its presence is deemed undesirable. In simplistic terms, less seeds means less opportunity for Poa annua to colonise an environment over time.

As a plant, Poa annua is by its very nature a pioneer species. Like similar plants low down the line of succession such as Cardamine hirsute (Hairy Bittercress), Poa annua has evolved to be one of the first plants to colonise challenging environments rapidly. As such, it expects environmental conditions may change rapidly, from hospitable to inhospitable. This is why, unlike the perennial grasses Agrostis spp., Festuca spp. and Lolium spp., Poa annua has retained the ability to flower profusely at low heights of cut.

Nutrition programmes have, in many cases, understandably been reduced to maintain plant health at acceptable levels rather than peak performance. It would be wise for turf managers to keep this under review, using their knowledge and expertise to guide them on a case by case basis. That said, inputs such as seaweed extract will help to prepare the plant for oncoming abiotic stress such as heat and water deficiency, so it would be advantageous to maintain applications. Plants treated with seaweed ahead of water stress events will also recover faster once soil moisture levels are replaced.

Water management is a vitally important aspect of maintaining any grass plant; a well maintained, professionally set up and prepared irrigation system, ‘ready and raring to go’, will be vital if water stress builds as we enter hotter weather. Soils with a capacity to manage water ingress and holding potential will be able to maximise available water and extend the periods by which plants are able to survive before irrigation is required. The continued application of water management products in the form of surfactant wetting agent programmes will significantly assist this principle and are to be recommended. This is because the efficacy of block co-polymer molecules requires a build-up in the soil to optimum levels over time - proactive approach, rather than a reactive one.   

Aeration, as ever, remains a vital component for optimum plant-soil ecosystem function. Wherever possible, continuation of efficient methods of aeration, such as star and sarrel tine rolling, will allow optimised soil life respiration and water ingression.

Insect pests populations have been elevated this year as mild winter weather and the end of old withdrawn insecticide use patterns combine, with many areas once again subject to secondary damage from predators. It may seem very low down the priority list currently, but active monitoring of insect activity now, to assist in optimising control through the summer, will pay dividends in minimising the problem and damage for next year. If chafer grubs are on your site, then installing pheromone traps in May allows you to plot their life cycle against integrated pest management plans and help inform treatment interventions later in the year. Whether that be substances on Emergency Authorisation, entomopathogenic nematodes, or a combination of both.

Writing this diary is always a balance of providing underpinning knowledge, insight and helpful reminders for the appropriate course of action to take at a given time of year; advice which must reach across the industry covering all sports, all levels, and budgets. With that in mind, one is always conscious that such advice should be there to be received by the reader on the basis that they take from it what is reasonable, relevant and practical for them and their facility. Never before have we been in a situation where facilities across all aspects of the industry are collectively faced with the challenges of balancing plant health, budgets and workloads to the extent we are now experiencing - in the midst of the ongoing global coronavirus pandemic.

It is then that the principle of taking from these writings what is reasonable and appropriate for you is more relevant than ever. As with any challenge or test life throws up, you can of course do no more than your best effort.

James Grundy
Senior Technical Manager – Amenity | MBPR

  • 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.

Used Machinery for Sale

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