4/2/2024 - By Dr. Paul Giordano

It's no secret that spiking weather patterns have a significant effect on turfgrass root systems throughout the growing season. In certain geographies, excessive moisture followed by extended drought conditions wreaks both abiotic and biotic havoc on turf stands. Such weather conditions open up turfgrass to vulnerability to other detrimental stressors.

That being said, it would be impossible to ignore plant parasitic nematodes, which often play a significant role in compromising turfgrass root systems and serve as both primary and secondary contributors to larger issues of root disease and dysfunction.

Nematode Prevention Can Be Complicated

Winning the belowground battle against nematodes can be complicated and often requires a balanced approach that includes cultural, chemical, and nutritional strategies. Because populations are dynamic, species are divergent, and life cycles fluctuate throughout the season, a proactive and integrated control program is often necessary.

This coupled with the fact that nematodes are frequently found in association with other root diseases such as Pythium root rot, summer patch, or take-all root rot - it’s clear that a holistic approach that balances pathogen control with root growth and health is needed.

Nematode Prevention | University of Florida Research

Harrell’s has worked with leading nematologist Dr. Billy Crow at the University of Florida over the last several years to evaluate the effect of different control products. The products were evaluated alone or in combination with proven soil amendment and root health products on overall nematode control and turfgrass health.

A key finding from this work showed that the inclusion of biostimulants, like seaweed extracts (found in Seaweed A+E among other Harrell’s solutions), fulvic and humic acids (found in Root Enhancer), and beneficial growth-promoting microorganisms (found in EarthMAX Organic) all play a significant role in optimizing conditions for root health and growth when used in combination with an effective nematicide program and a high quality penetrating wetting agent like Fleet.

Nematode Prevention | Treatment Methods

Treating nematodes is usually done most effectively during the spring and early summer when plant parasitic populations typically begin to grow and proliferate.

As shown below in the program implemented throughout the Harrell’s/UF research study, more severe infestations with multiple species such as lance, sting, and root-knot require season-long applications to keep populations in check. Rotating through effective nematicides while incorporating effective fungicides and root health supplements has been shown to be the best strategy for optimal control and turf quality. 

Seasonal Nematode Prevention

Spring and fall are both great times to put a primary focus on root growth and the health of intensively maintained turf stands. Cool-season grasses such as Poa annua and creeping bentgrass are pushing new growth and recovery from either summer or winter stress. The moderate soil temperatures tend to trigger carbohydrate and resource allocation to belowground tissues, preparing turf for summer performance or winter dormancy.

Conversely, root growth is not necessarily optimal in warm-season grasses like bermudagrass, seashore paspalum, and zoysiagrass in the spring and fall timeframe. The cooler weather often results in a slow, but steady retraction of root systems which can allow nematode damage to be more pronounced. Using Harrell’s products that aid in root growth, density, and function throughout the growing season can help to maintain overall turfgrass health during what is often peak play (and stress) through cooler times of the year.

Reach Out to Your Harrell's Rep!

For more information on nematode prevention, building up your roots, preparing for fall/spring or any other inquiries, reach out to your local Harrell's rep! They're here to help.