Sports Turf Agronomy Advice - November 2024
A welcomed dry end to October, which is a stark contrast to the weather we were contending with at the same time last year. To accompany this drier period, we have also had favourable temperatures which have continued to provide growth and recovery for many.
That’s not to say it hasn’t been wet; there have been days of significant rainfall, however, in-between these spells there have been good days. This I think has a major impact subconsciously on how the autumn/winter ‘feels’. Take last year for example, with October being a wash-out, the run up to the year-end seemed extremely long. Whereas, with a favourable October, winter is kept at bay for another month and the main playing (growth) season keeps going and the run into Christmas feels much shorter.
In November, we enter a period where there is a shift towards more undesirable factors and away from conditions which benefit the grass plant. Mainly because there is less available sunlight for photosynthesis, coupled with lower temperatures creating a reduction in growth rates and prolonged leaf wetness, because of less dry-down time throughout the day. The average daylight hours for the month are 8.57 hrs, down from 10.47 hrs in October, with an average of just 65 hours of sunlight for the month. This is before you even consider shade from surrounding trees or buildings! These factors favour competition for grasses from mosses, algae and fungal diseases. One of the main fungal diseases in the UK throughout this period is Microdochium nivale.
Click here if you want to review weather data in your region for October. To keep up to date with the weather throughout November visit https://academy.agrovista.co.uk/category/weather
The forecast for early November is for the drier weather to continue, which will keep surface conditions favourable, allowing for essential maintenance work to be carried out without having an impact on soil structure. Towards the middle of November, things are predicted to become unsettled with regular showers and night-time temperatures also reducing. Things are unlikely to pick up from this point in terms of temperatures, with any significant effect; therefore changing product applications in line with this is recommended.
Disease pressure has been reduced in October compared to September, but with long periods of leaf wetness and temperatures in an ideal range, it pays to be mindful of predicted disease pressure and prime the grass plant to withstand any pressure as much as possible. Newer fungicide chemistry means that applications, if needed, should be made preventatively (not prophylactically) through close monitoring of disease pressure and the likelihood of disease occurrence. Essentially, pre-empting when all three factors of the disease triangle are likely to coincide for an outbreak of disease. There are numerous factors to consider, but nutrition and water management are two of the main elements to address.
With low base nitrogen requirements, aim to promote steady, hardy shoot and leaf growth, avoiding surplus applications where flushes of growth become more susceptible to attack by fungal pathogens. The demand for year-round play on quality sports surfaces increases plant stress and the requirement for recovery, putting an increased emphasis on ensuring the right choice of nitrogen source as well as the amount applied.
Micronutrients and biostimulants are not to be overlooked, with Iron traditionally used to enhance turf colour, with fewer of the negative aspects associated with excessive nitrogen fertilisation, such as outbreaks of certain diseases. Applications of seaweed will elicit important beneficial defensive and stress responses in the plant.
Water Management
Water plays a major role in the development of fungal turf diseases, so it is as important to have a water management strategy for the autumn/winter period as it is for dealing with drought stress in the summer, albeit potentially different chemistries. Maintaining appropriate water/air ratio is a key factor in reducing turf stress during periods of the year when rainfall increases, and drying opportunities are reduced.
Aeration timing and methods can make all the difference; sarel rolling can aid water infiltration and help surface drying with minimal disruption, with slitting giving contact to a large surface area within the soil for maximum gaseous exchange, again with minimal disruption to the surface. More heavy-duty aeration such as verti-draining can also be carried out as needed, but ideally when ground conditions are suitable.
The use of penetrant wetting agents and dew dispersants are now commonplace in a bid to keep surfaces as dry as possible and restrict the occurrence of disease outbreaks. When using a penetrant wetting agent, it increases the infiltration of water into the soil profile, ensuring that the water has a route into and, critically, out of the upper rootzone. This is only successful if there is sufficient drainage for the water to move away. Otherwise, surfaces can actually become wetter.
Worms
Worms continue to be a focus for turf managers with the increased soil moisture levels. There are no legal controls for earthworms and any product which is applied to directly affect them is done so illegally.
Continue with cultural management practices, such as localised surface acidification, removal of grass clippings to reduce their food source and sanding of surfaces to assist in the drying out and dispersal of casts. Sulphate of iron is often used as a surface acidifying agent, but it is worth considering that over application may lead to an accumulation of iron in the soil and reduction of pH causing long term imbalances and negative effects to plant health throughout the rest of the year. Consider utilising some other product choices without these negative effects to maintain a balanced approach.
Tom Wood
B.Sc (Hons) | BASIS | FACTs