Maintaining Good Playing Conditions Through Late Summer.
It’s late summer and it’s the time of year when golfers and members expect the course to be at its best, pristine, and free from blemishes. But often as we head into this part of the summer many golf courses are feeling the strain. There have been long days with many rounds played, and the course is suffering from too …too hot, too dry, too wet, too humid, and too busy!
Ground Staff are also beginning to tire. A combination of early mornings, long days and working in the heat can be very stressful. Despite all the toos, we need to keep our eye on the ball and persevere and do what greenkeepers do best, knuckle down and prioritise maintenance practices to continue to produce great playing surfaces!
What can be done though to maintain the quality during this demanding period? Long summer days are when most people play golf, the course is at peak condition and this is due to the maintenance programs in place, and the hard work of the staff.
What can possibly go wrong? Excessive heat, moisture, humidity, heavy traffic and play, disease, and nutrient stresses are key problems that can arise at this time. Maintaining healthy turf and excellent playing conditions during the summer is the turf manager’s priority but requires flexibility in management techniques, so you can minimise these stresses.
Dealing with adverse weather conditions.
Firstly, no matter where in the world your facility is based, the weather can wreak havoc, long periods of hot dry weather can lead to severe pressure on the course. The first symptoms of heat stress usually appear in combination with another stress, most commonly traffic stress. Turf managers have to be ready to contend with high temperatures and drought stress. Ensure that all areas of the course are correctly irrigated by regular inspections. Hand watering may be required on slopes, high spots, or areas difficult to access.
Most maintenance programs include regular applications of surfactants, and this is crucial.
A surfactant program will help alleviate localised dry spot (LDS) and improve moisture uniformity. Research shows surfactants will also increase the efficacy of irrigation and of any rainfall during this period.
During heat/drought periods like this it’s a good idea to increase Height of Cut on closely mown areas. This, alternated with lightweight rolling will reduce stress while maintaining playing qualities.
The opposite of this weather-related stress of course is prolonged heavy rain.
Hot, wet, humid conditions can cause significant problems for turfgrass. Waterlogged soils limit rootzone aeration and will adversely affect turfgrass growth and development, lead to a shallow root system, reduced leaf quality, reduced plant vigour, and increased disease susceptibility. Excessive moisture during summer can also elevate soil temperatures and facilitate numerous related problems.
Again this is where a good surfactant program will help. As well as helping with moisture retention during dry periods, surfactants, because of their unique combinations of hydrophobic and hydrophilic molecules, will enhance infiltration and percolation, while maintaining consistent levels of soil moisture, when compared to untreated areas.
Another procedure to help during summer stress is venting.
Venting, using small-diameter solid or needle tines, slicing knife tines, cross tines, star tines and micro tines, used at shallow depths on a tight spacing will break the surface and create channels for gas exchange. This helps to dry out the upper profile where the roots are most active and dense. Air holds less heat than water, so increasing the air to water ratio in the upper portion of the rootzone will also keep the rootzone cooler, helping the turf survive heat stress.
Sand topdressing and Verticutting are crucial procedures carried out on a regular basis through summer and provide benefits such as:
- Organic matter dilution
- Surface smoothing
- Crown protection, resulting in decreased susceptibility to anthracnose disease.
- Removal of excessive leaf growth which contributes to puffy, soft surfaces.
- Improved mowing quality and surface smoothness.
- Reduction of lateral growth and promotion of an upright growth habit.
These operations ensure high quality playing surfaces; however, timing is crucial. If conditions are excessively hot and dry, or your surfaces are displaying any signs of stress, then defer these operations.
Remember, cool-season grasses can be injured by such programs during environmentally stressful periods.
Nutrition is crucial in maintaining the high standards you’re aiming for. Your course is constantly under extreme stress…low mowing heights, high levels of traffic, extreme weather, and a balanced nutritional program can help maintain growth, alleviate wear, and aid recovery.
Depending on a number of factors, fertility inputs can vary from regular light applications of Urea to a complex program of nutritional products and defence activators, this depends on your situation, turfgrass species and choice of the Superintendent. Bear in mind also, that Phosphite, Seaweed and Silica have all shown to help prepare turfgrass for periods of both abiotic and biotic stress.
Whichever road you take, nutritional applications should coincide with environmental conditions, the use of Growth Potential is a useful tool for timing these operations.
Fertility is only part of the story when it comes to managing growth on sports surfaces. Plant growth regulators (PGRs) are a key component of many agronomic programs and help maintain consistent playing conditions.
PGRs provide numerous benefits: reduced clipping yields, enhanced turf color and tiller density, improved turf quality, reduced nitrogen requirements, and importantly, increased stress tolerances. PGRs can be used throughout the course on greens, tees, and fairways, and roughs. Mowing frequency can be reduced and clippings properly dispersed with less clumping.
To maximize PGR potential, and to sustain season-long growth suppression, it is important to use growing degree-day models (GDD). These are vital in timing PGR applications as it disregards calendar-based intervals and bases applications on plant metabolism.
Key point to note: During period of high stress, do not apply pesticides, fertilisers, or combinations of products that have the potential to burn the turf. If possible, apply during cooler evening hours or defer treatments until temperatures moderate, when the turf can tolerate the applications better.
Disease:
In most geographic areas summer provides ideal conditions for turfgrass disease. Temperate areas such as the UK and Ireland contend primarily with Anthracnose, Red thread, Fairy Ring and increasingly Dollar Spot. In the US and continental locations however, there is a much wider and diverse range of disease problems, due to the more extreme environmental conditions.
The turf manager must identify the predominant pathogen in their facility and be proactive in their management program to reduce conditions conducive to infection. This may entail judicious inputs of nutritional products, and surfactants, incorporation of lightweight rolling, the use of defence activators and of course a fungicide program tailored for the specific pathogen.
Cool-season grasses, especially Poa annua, in particular are very vulnerable, they are at their most susceptible because the high respiration rates, which are driven by high air and soil temperatures, drives excessive shoot growth that firstly can leave playing surfaces puffy and dense, but also because the excessive growth can deplete and carbohydrate reserves in the plant weakening them and reducing their stress tolerance. With environmental conditions ideal for pathogens and the turf in a weakened state this means disease pressure is extreme.
Something I have often said regarding disease control: Know your enemy!
- Influence as many factors that contribute to conducive conditions for disease.
- Employ cultural practices which will enhance your turfgrasses ability to withstand pathogen challenge.
- Employ a balanced nutritional program and include elements and compounds which have been shown to have suppressive properties.
Disease management must always include an integrated approach that combines cultural, nutritional and chemical practices. And remember, when using a fungicide program, use best management practices to avoid possible resistance buildup.
- Fungicides are most effective when combined with cultural and nutritional practices that reduce plant stress and prime them to withstand challenges!
Main points
- During the last months of summer the priority is to continue to present your course at its best.
- There can be numerous challenges outside of your control to overcome.
- Excessively inclement weather can be problematic and lead to significant damage.
- Programs which include regular venting, surfactants, PGRs, balanced nutrition and a proactive approach to disease control will help ensure your course meets the challenges head on and continues to present and play well.
- Your ongoing maintenance program has to have inbuilt flexibility in order to meet any challenges.
- Aeration, topdressing, verticutting, fertility and other inputs may have to be amended to ensure reduced damage and to maintain your standard of playing surfaces.
When you finally get to the cooler and shorter days then it’s time to prepare for Autumn!