The process of sampling for nematodes is rather simple. The number of samples required will depend on the size, use and characteristics of the area. A sample should be representative of the turf area to be sampled or the turf area thought to be infested with nematodes. The area of the turf should be subdivided into areas that share similar grass species, topography and soil types because these factors can affect micro-environments of nematodes.
Numbers of nematodes are usually highest in the fall, making the fall a good time to sample. Sample in areas that are exhibiting symptoms or in areas between dead and injured grass. Areas of dead grass will have fewer nematodes because there are inadequate resources for them. Also, collect samples when soil moisture is not too wet or too dry.
Step 1: Evaluate the area to determine the number of soil samples that will be required. Large areas or areas with different turfgrass species, soil types or topography will require more than one soil sample.
Step 2: Collect samples of the turfgrass and soil using a soil probe to a depth of 6 to 8 inches from 15 to 20 spots within the sampling area. Be sure that core samples are spaced in a uniform pattern.
Step 3: Mix soil cores together and place one pint of the soil and root mixture into a plastic bag. Roots should be included because some nematodes are found only in roots. Seal the bag and label it. Include as much information regarding the sample location as possible, including your name, phone number and email; the date the sample was taken; your parish, street address, city, state and GPS coordinates, if available; grass species, topography, soil texture, and history and future plans for the turfgrass.
This information helps to provide better recommendations for your situation.
Step 4: Hot or cold temperatures and dry conditions will kill sampled nematodes. Protect collected samples by placing the sample in a place that will remain at room temperature. Keep the bag out of direct sunlight.
Step 5: Fill out a Nematode Advisory Service (NAS) form for each sample and promptly submit samples following collection. More information regarding nematode sampling and analysis can be found on the Nematode Advisory Service website.
Step 6: Mail samples, forms and payment to:
Nematode Advisory Service
302 Life Sciences Bldg. – Department of Plant Pathology
Baton Rouge, LA 70803
Systematic pattern for sampling a routine check across the lawn
Pattern for sampling a problem area in the lawn
Soil probe used for sampling
Mixing samples in a bucket
The LSU AgCenter and the LSU College of Agriculture