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Program approaches for season-long nematode management

Nematodes are microscopic roundworms that feed on turfgrass roots. Their activity reduces root depth, density and function, creating turf that is more prone to drought, heat, nutrient deficiency and stress-induced diseases. Where nematodes are present in damaging numbers, protecting the turf from nematode feeding can help to maximize root growth and create high-quality, stress-tolerant turf. 

Today’s nematicides must be re-applied on regular intervals to maintain protection of the root system. Effective nematode control requires a programmatic approach, similar to fungal diseases, and Divanem® nematicide is the foundation of a successful program for several reasons:
  1.  Divanem controls all of the major root-feeding nematodes found in turf. Nematodes are almost always present as a mixture of different species, and controlling a subset of them will allow others to increase and cause turf damage. For example, lance and spiral nematode populations can increase after applications of Indemnify® nematicide, whereas Divanem provides effective control of these species and will prevent them from increasing. 
  2. Nematodes are active throughout the growing season when turfgrass roots are actively growing, so effective management often requires repeat applications. Divanem can be re-applied four to eight times per year at the 12.2 and 6.25 fl. oz./A rates, respectively, to protect the roots over a significant portion of the growing season.  
  3. Just like with fungal diseases, rotating nematicide chemistries is crucial to long-term success. Nematodes can develop resistance to nematicides, and enhanced degradation driven by shifts in soil microbes can reduce the residual of certain chemistries. Divanem delivers a unique chemistry that has not been historically applied to turf and is not widely used for control of other turf pests.

A field trial was conducted with Dr. Bruce Martin at Clemson University to show the benefit of a nematicide program and compare different product sequencing. This trial was conducted on Tifdwarf bermudagrass maintained under putting green conditions in Florence, South Carolina and was infested with sting, root knot and spiral nematodes. Applications were initiated in the fall of 2016 and continued through the spring of 2017, and turf quality and nematode populations were monitored throughout the summer of 2017.

The best treatment based on turf quality and nematode populations was a rotational program where one application of Indemnify (17 oz./A) was followed by two applications of Divanem (12.2 fl. oz./A) on a 28-day interval, both in the fall and spring. While four applications of Indemnify provided complete control of sting nematodes, this Indemnify-Divanem program also kept sting populations to acceptable levels and provided better management of root knot and spiral nematodes. 


% Turf Cover

Root Knot Nematodes

Sting Nematodes

Spiral Nematodes






Indemnify (2X fall, 2X spring)





Indemnify (2X fall) Divanem (4X spring)





Indemnify (1X fall and spring) Divanem (2X fall and spring)





Turf cover was evaluated on May 30, 2017 on a percentage scale. Nematode samples were collected on June 26, 2017 and assessed as number of individuals per 100 cubic centimeters of soil. Source: Clemson University, 2017.

Fungicides can play an important role in nematode management. Several turf diseases, including summer patch, take-all patch and Pythium root rot are often more severe in areas with damaging nematode populations. We consistently see improved turf performance when nematicides are used in conjunction with a comprehensive fungicide program. Tank-mixtures of Divanem with Velista® or Heritage® Action™ fungicides increase turf quality and provide excellent control of soil-borne diseases like fairy ring. Divanem and Heritage Action are also packaged together as part of one convenient Multipak

In the example below, tank-mixtures of Divanem and Velista improved overall turf quality and provided excellent fairy ring control compared to Divanem alone. View examples of complete agronomic programs for your area.

Treatments applied three times on 21-day interval. Photos taken November 6, 2017. North Carolina State University, 2017.

For more information about nematode control, visit GreenCastOnline.com/NematodeKnowledge, or download the GreenCast Turf App for both Apple® and Android® smartphones and tablets to help streamline the tank-mixing calculation and record-keeping process. You can also visit GreenTrust365.com/SeasonalProgram for more information about the Divanem Nematicide Offer and how to receive an Amazon Echo Spot.

Amazon and Echo Spot are not affiliated with and are not sponsors of this Program.

©2018 Syngenta. Important: Always read and follow label instructions. Some products may not be registered for sale or use in all states or counties and/or may have state-specific use requirements. Please check with your local extension service to ensure registration and proper use. Divanem is a Restricted Use Pesticide. Divanem®, GreenCast®, Heritage® Action, Velista® and the Syngenta logo are trademarks of a Syngenta Group Company. Amazon, Echo and all related logos are trademarks of Amazon.com, Inc. or its affiliates. All other trademarks are the property of their respective owners.