Root-Knot Nematodes

About Root-Knot Nematodes

Nematodes are microscopic roundworms that feed on plant roots, and root-knot nematodes (Meloidogyne spp.) are the most damaging group in turfgrass. They are terrifying because the damage is invisible until it is catastrophic — by the time you see above-ground symptoms, the root system has already been devastated. We encountered a textbook nematode case on a three-acre Zoysia lawn that looked amazing all summer long. The lawn was put to bed correctly going into fall, went uniformly brown for dormancy — and the following May, roughly thirty percent of the lawn simply did not wake up. It stayed brown. The customer wanted us to re-sod the dead areas at an estimated cost of sixty thousand dollars. Instead of sodding, we ordered a nematode assay from the University of Tennessee. The test confirmed root-knot nematodes in the soil. That sixty-dollar test saved sixty thousand dollars — because re-sodding over nematode-infested soil would have been pointless. The new sod roots would have been attacked immediately, and the same die-off would have repeated the following year. Nematode damage is one of the reasons we specialize in fescue and do not currently service Zoysia or Bermuda lawns. Warm-season grasses in Middle Tennessee are susceptible to nematodes, chinch bugs, and large patch on top of the same fungal diseases that affect fescue — the liability and complexity of managing those additional pest pressures is significant. If you have a warm-season lawn (Zoysia or Bermuda) and large sections fail to green up in spring after an otherwise healthy-looking fall, request a nematode assay from the University of Tennessee Extension before spending money on sod or seed. The test is inexpensive and can save you from a very costly mistake. For fescue lawns, nematode damage is rare but not impossible. The standard grub and insect control program does not address nematodes — they require different diagnostic and treatment approaches.

Root-Knot Nematodes (Meloidogyne spp.) is a landscape pest commonly found in Middle Tennessee, including Columbia, Thompson's Station, Spring Hill, and the surrounding areas. This entry is part of our Landscape Pests identification guide.

As lawn care and treatment specialists, we encounter Root-Knot Nematodes regularly when servicing properties across the region. Proper identification is the first step toward effective pest management that protects both your turf and your landscape plantings.