Intense turf stress

This summer has seen the hottest recorded temperatures within the UK. It seems likely that 2021, which was declared the hottest European summer since 1500, may fast be replaced by summer 2022 as the holder of this dubious record. Europe's five hottest summers have been recorded in the last two decades, meaning turf managers are having to cope with these extreme conditions far more frequently. For turf managers throughout Europe, this summer has been a period of intense turf stress.

These extreme weather conditions sometimes call for a change in approach, and many turf managers are considering what options are available to deliver more resilient turf surfaces which are better placed to cope with heat and drought, as well as the necessary mechanical turf stresses required to deliver high performance playing surfaces.

Revisiting turf nutrition can be useful, and the Aquatrols Redox TurfRx product range has some key products specifically designed to assist the turf manager in these difficult situations. The range incorporates eleven distinct types of soluble carbon chemistries with plant nutrients to dramatically improve plant uptake, input efficiencies and results.

Plant Strength and Root Development

Prolonged periods of drought and heat stress can result in weaker grass plants and sparser root systems. As turf managers look to strengthen the plant and re-establish strong root systems after challenging periods, the application of calcium within the nutritional programme should be considered.

Calcium plays a critical role in turf health and quality. Plant available calcium is essential for turf nutrition, health and quality but it can only be absorbed in its ionic form. Calcium plays several critical roles in plant nutrition; two of the most important being root growth and cell wall structure.

In the absence of soil solution calcium, root growth will cease. Calcium is critical for root growth and development. Directly behind the root cap is the zone of highly active cell division that actually promotes root growth. As calcium is critical in cell structure and membrane stability, the soil solution concentration of calcium will determine root growth and root system development.

The majority of plant calcium is found in the plant cell walls, mainly in the outer portion of the wall. Pectin is a structural carbohydrate in plants. Plants higher in calcium will form calcium pectate. Calcium pectate is the main form of pectin in plant cell walls. The amount of calcium and calcium pectate in cell walls directly affects its form and function. Plants high in calcium pectate will have improved cell wall structure and will be less susceptible to turf weakness and disease damage.

Within the Aquatrols portfolio we have two products containing plant-available calcium: TurfRx Ca and TurfRx Si. The particular manufacturing process involved in achieving this is called micro-encapsulation. This unique chemistry results in tank-mixable and soil-stable calcium, thus preventing calcium tie-up and allowing this critical mineral to be transported to soil micropores. It is in these micropores that calcium is influential in improving soil structure.

Micro-encapsulation is also important in calcium plant nutrition. As the plant absorbs water, it also absorbs the minerals within that water. Micro-encapsulated calcium can be absorbed into plant roots via water transpiration. Once inside the plant, this breaks down and ionic calcium is delivered to the plant for utilisation in its associated metabolic processes. The role that calcium plays in sports turf management regarding both soil structure and plant nutrition is well known. What tends to be less well known is that the form of calcium that is supplied into the situation is critical, and both TurfRx Ca and TurfRx Si are able to deliver calcium in the correct form for maximum plant utilisation.

Heat and Drought Stress

TurfRx OxyCal has been proven to reduce turf stress caused by extreme heat, whilst TurfRx C-85 improves synthetic nitrogen efficiency as well as promoting soil microbial diversity and soil health. These two products, applied in combination on a fortnightly basis, have been demonstrated to deliver improved turf quality performance while these conditions persist. This combination of products is ideally suited to use during periods of heat and drought stress.

Turf Surface Recovery

Surfaces that have been weakened or thinned by drought stress, high wear or disease activity will often benefit from appropriate applications of nitrogen. Nitrogen is an essential component of chlorophyll, amino acids, proteins, nucleic acids and enzymes. It influences shoot and root growth, shoot density, cold and drought hardiness, colour, recuperative potential and disease susceptibility.

We, as an industry, have generally understood the need to reduce nitrogen inputs in line with the needs of particular sports turf surfaces and the requirements of specific grass species. We are not driven by crop yields and although we understand the need for vegetative growth, we are far more focused on managing plant growth in accordance with certain performance targets.

A combination of TurfRx C-85 and TurfRx Supreme, applied monthly with soil temperatures of 10°C and above, provides turf managers with the opportunity to reduce nitrogen input with extended application intervals.

Within the turf management sector, there has been an increasing demand to reduce nitrogen inputs whilst also producing playing surfaces of the highest quality. TurfRx C-85 increases nitrogen efficiency. When combined with synthetic nitrogen, TurfRx C-85 will increase nitrogen efficiency by at least 25%; this is of additional interest at the current time with world economic events driving up fertiliser costs.

Synthetic nitrogen fertilisers applied to the soil all tend to eventually stabilise in the nitrate-nitrogen form due to microbial interactions. In the nitrate form, nitrogen is extremely mobile in the soil and, if the nitrification process is on the surface, nitrous oxide is volatilised. Forty to sixty percent of applied nitrogen is commonly lost to a combination of volatilisation and leaching.

A simple and highly effective method for reducing nitrogen losses is the use of TurfRx C-85. This is a reacted soluble carbon nutrient product designed to improve soil microbial activity. It contains short, medium and long-chain soluble carbon compounds. Improved soil biology incorporates nitrogen into biological processes, effectively maintaining nitrogen within the rootzone.

In addition, TurfRx C-85 can be used to control clipping yields when felt necessary, the nitrogen metabolizer assists in the reduction of both nitrogen inputs and PGR use and is a key product to consider employing within grass species transition programmes.

TurfRx Supreme dramatically improves the plant's ability to properly metabolise nitrogen. It is specifically formulated to target plant sugar alcohol production related to nitrogen metabolism in plants. The combination of plant nutrients and increased sugar alcohols will enhance nitrogen metabolism. This is a reacted plant nutrient product that contains soluble carbon compounds derived from a proprietary fermentation process, and can lead to improved amino acid and protein production and thereby improve overall turf quality and performance.

Nematode Damage

Plant parasitic nematodes were once considered a problem that only affected golf courses in the southern United States. Now, however, there is increasing concern about these particular nematodes among sports turf managers globally. Sand based rootzones provide an ideal environment for nematodes. Profiles like this provide the nematodes with a uniform host along with a long growing season. The soil makeup is 75% to 95% sand, which provides ideal pore space for oxygen, water and nematode mobility. In addition, sports turf on sand based rootzones is irrigated frequently, thereby favouring nematodes that require moisture for survival and mobility. The widespread adoption of sand-based constructions has undoubtedly been a contributing factor to the increased frequency of nematode issues.

Nematodes can weaken turf roots, making them less efficient at translocating water and nutrients. Therefore, one of the first symptoms of damage is an increased tendency for the grass plant to wilt. Subsequently, the shoots may become stunted in irregular patches and appear yellowish, and eventually symptoms progress to turf thinning. Even when nematode damage is low level, it can make turf surfaces more vulnerable to environmental stresses including disease activity. In severe cases, nematode activity can cause affected grass plants to weaken and die back. These symptoms can also be attributed to numerous other environmental and pest stresses, making identification difficult.

TurfRx NatureCur is a botanical extract product that contains 5% potassium. This product results in grass plant tissue becoming less palatable to the plant parasitic nematodes, whilst not being harmful to beneficial nematodes such as the predators and fungal and bacterial feeders. NatureCur also contains proprietary soluble carbon compounds that improve antioxidant production and stimulate root growth and metabolism.

When integrated into a comprehensive nutrition and soil health programme, NatureCur allows for positive root growth under conditions of severe abiotic stress. Stress factors, such as soil chemical imbalance and soil biological imbalance, always precede damage from nematodes.

TurfRx NatureCur optimises root quality and quantity; both being essential for water and nutrient uptake. By increasing the relative strength and viability of root metabolism, the foundation for healthy turf growth and surface resiliency can be achieved.

The Aquatrols Mission

Aquatrols is committed to pioneering new methods that advance conservation and health for agriculture, turf and horticulture. The Redox TurfRx range offers new technological solutions for the modern turf manager. As summer weather conditions make the development and retention of high-quality turf surfaces progressively difficult, so these new products have an increasingly significant role to play in the turf management process.