Sports Turf Agronomy Advice - June 2023

We head into June on the back of a dry period which has seen minimal rainfall over the last couple of weeks. The dry weather has been accompanied by an increase in temperatures which has meant, for the first time in the year, we have had consistent growing conditions.

However, this hasn't been without its challenges as the recent prolonged dry weather is now causing turf issues, with watering becoming increasingly important.

An overview of the weather statistics for May can be found below. The GP for the first week continued the upward trend from the end of April, and by week two, GP was above 70% and has remained similar throughout May. Rainfall was impacting on what maintenance work could be carried out in early May, however by week 20 and 21 there was only 1.5mm of rainfall (on average).

Click here if you want to review weather data in your region for May. To keep up to date with the weather throughout May visit https://academy.agrovista.co.uk/category/weather

Looking at June's long-term forecast, temperatures are expected to be good for the time of year with 13 days on or above 20°C. It also looks like it will continue to be dry month, with only 4 out of the 30 days predicted to have any rainfall; meaning that wetting agents and irrigation systems are likely to be crucially important for the month.

Wetting agents

The use of wetting agents can be key to providing consistency in moisture management throughout a rootzone. The aim being to have even moisture distribution through the rootzone, within a determined ±% tolerance set by the turf manager, which helps eliminate any excessively dry or wet spots and provides optimum turf health and performance. This practice, not only helps promote good rooting but also assists efficient nutrient uptake, maximising any inputs that have been applied. Early applications of block co-polymers will now have some accumulation in the soil and will help maintain surface quality through any dry periods should they appear. If early applications couldn't be made, then a penetrant wetting agent will help break surface tension and allow infiltration, although water holding will be minimal with this technology. Hand watering should take place where possible to reduce the risk of over watering, which can have a negative agronomic effect; automatic irrigation systems can be used to ensure any daily losses through evapotranspiration (ET) are replaced.

Cultural methods go hand in hand with such a programme and regular sarrel rolling keeps surfaces open, allowing water to infiltrate and encourages gaseous exchange. This can be followed up with regular pencil tine aeration to create deeper channels for water movement and root development.

Plant growth regulators (trinexapac-ethyl and prohexadione-calcium) applied throughout the growing season can mitigate stresses through dry periods. The deeper rooting which is promoted allows the grass plant to cope better with stresses and ET rates have also been seen to be reduced, meaning the plant is put under less water stress and can conserve more energy. Furthermore, there is then less irrigation water required each day to replace ET losses, which is more sustainable turf management. To further encourage deep rooting, a drench of the profile, followed by a dry down period, will encourage roots to penetrate down the profile and search for water reserves. In comparison, regular little and often approach only serves to keep the upper profile moist, can lead to soft surfaces, promote annual meadow grass dominance and encourage disease.

Pests

We have now had the long-awaited confirmation that Acelepryn has achieved full registration and does not require an emergency authorisation for applications to be made. Full details can be found in the Pitchcare update here.

There has been a label change in comparison to what was permitted under the emergency approval, so ensure you follow the guidance on the label to make certain it can be applied to your turf area. Also, what total area is allowed to be sprayed, as there are still restrictions on use in place. Speak to your BASIS qualified advisor who will be able to talk you through the application guidelines to follow. You can also find all the relevant information on the Syngenta website here.

We are entering peak chafer grub activity, so it is important to regularly monitor and record any activity so that informed decisions can be made about the best time to make any product applications.

Entomopathogenic nematodes can be made on sites where the label does not permit full application to the whole area. Apply 4-5 weeks after the peak adult flying time has been recorded, ensuring that:

• The number of larvae in the soil has reached the action threshold.
• The soil temperature is within the tolerance limits for the nematode.
• The soil is moist and has been aerated.
• Further rain is forecast or you can apply irrigation after application.

Tom Wood
B.Sc (Hons) | BASIS | FACTS