Sports Turf Agronomy Advice - October 2023

As we start October and what can be seen as the true beginning of the autumnal conditions, memories of summer are in the back of everyone's minds. Since the June drought, the wet conditions in July and August have created challenging conditions for many.

Microdochium patch developing on turf surface

Syngenta

Following this, September threw up sharp fluctuations in weather extremes; something which is seemingly becoming more the 'norm' as each year passes. Many of you may have recently attended GroundsFest, the new trade show which combines indoor business and education opportunities with outdoor demonstrations. Feedback over the two days, which had a mixture of weather, was very positive, from both end users and exhibitors.

Looking at the weather in September, from across the UK, shows we had an average of 81.2% growth potential (GP), which is a significant difference to last year where GP dropped to the 60% mark. This year, growth has remained strong with only a slight drop off in week 38. Growth has been boosted this month by the week of unusual high temperatures we experienced. Temperatures remained consistent with an average of 17.3°C highs and 11.2°C lows, which is up from last year's 9°C, which again has helped maintain healthy growth and recovery. Rainfall has been around 50mm on average, which has meant a drier month in comparison to last year, with a consistent base nitrogen which has allowed for favourable conditions for renovation work. The base nitrogen requirements figures were 6kg of N per week at the start and finish relatively high at 4kg of N per week.

An overview of the weather statistics for September can be found below. Click here if you want to review weather data in your region for September. To keep up to date with the weather throughout October, visit https://academy.agrovista.co.uk/category/weather-2023

Temperatures for the start of October look to remain favourable around 15°C, which will benefit those who are trying to get recovery from maintenance and repair from any disease outbreaks. Although the weather also looks unsettled, with over 50% of the days at the beginning of the month with rain forecast. However, the end of the month looks more settled with clear days, but typically for the time of year the temperatures start to fall to around 10°C and you would expect to see soil temperatures start to decline and growth slow.

Integrated pest management

There has been significant leaf wetness in September, which in combination with the fluctuations in weather, both wet and dry and warm and cool, means that disease management is paramount for October. With all the best practices in the place, sometimes the weather element is too substantial, and disease breaks out. It is, however, having these best practices in place that can be the difference between a severe outbreak, which will take a significant amount of recovery, or a minor outbreak which will recover relatively quickly. The turf manager's challenge is to balance the right amount of fertility to keep the plant ticking over and optimize plant health through the use of bio stimulants.

Whilst reducing the probability of disease incidence, using proven fungicidal chemistry, surfactants that minimise leaf wetness and cultural practices to maintain a healthy growing environment. Weather data is also a valuable asset when utilising an IPM plan. One example being, compared to last October, the difference in base nitrogen requirements is around 2kg/N/ha more at the start of the month. Therefore, over the month of October, depending on weather patterns, you could potentially require anything from 4-8 kg of N more this month compared to 2022. This highlights where using the same product at the same time of year at the same rate, because it had good results last year, may not yield the same results following this year's application, as the plants' requirements are not the same.

There has been a recent product update in Fungicide availability. The dual-action Syngenta turf fungicide Ascernity^® has an approval update. Previously only available in Ireland and in enclosed spaces in the UK, it has now gained additional approval for use on golf greens and tees. For those managing these areas, it will be a welcome addition in the toolbox for maintaining turf surfaces through the autumn period.

Pests

Adult crane fly activity has historically peaked around mid-September, meaning that towards the end of October will be the key timing for Acelepryn applications for those using it for leatherjacket control. For those with high populations to manage, entomopahogenic nematodes can also be applied with the right soil temperatures and available moisture being required to get the best out of an application. These can be applied in conjunction with an Acelepryn application to achieve the highest efficacy of control, or they can be used at higher rates as a stand-alone application. It may also be useful in situations where only a few localised areas require both applications rather than blanket sprays.

Worms

The rise in moisture levels means that earthworm casts are now a serious issue again for many; with them being a major factor in the 'damage' to turf playing surfaces, which can affect playability and visual presentation greatly. There are no legal controls for earthworms and any product which is applied to directly affect them is done so illegally. Cultural management is the only route currently available and efforts in this area should continue as part of a long-term strategy to create an environment in those worse affected areas that will minimise the impact of worm activity. In this scenario, worm casting will be reduced, and casts will be easier to clear away without the smearing effect on the turf surface. Surface acidifying agents can be used as a deterrent, but it is worth using with caution to avoid over application which may lead to negative effects to plant health throughout the rest of the year.

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