Soil sampling is best for insects that remain in the soil such as billbug larvae and white grubs. Removing the sod allows you to assess your insect populations and determine whether treatment is necessary.
Step 1. Use either a cup cutter, shovel or sod cutter to sample a square yard (1 square meter) area of turfgrass (cup cutter sampling is pictured).
Step 2. If using a cup cutter or shovel, slowly break apart the soil, and examine the lower 1-3 inches (2.5-7.6 centimeters) for insect larvae.
Step 3. If using a sod cutter, roll back the turf like a mat. Slowly rake through the soil and examine for larval insects.
Step 4. Count the number of insects found in the area; determine whether treatment is necessary.
The following insects can be monitored with soil sampling:
- Billbug larvae
- White grubs