Nightcrawlers, also known as Lumbricus terrestris, are a kind of worm commonly found in gardens and yards. These worms prefer moist, cool conditions. The worms are called nightcrawlers because they typically come out at night when temperatures are cooler. They are different from garden earthworms because they have one end that is darker than the other and a flat back end. The presence of these worms can cause trouble for lawns and gardens if the population gets too high.
Create a mixture of soap and warm water. Place about 1/4 cup of soap into a 5 gallon bucket. Pour the soap mixture over the areas where the nightcrawlers are most concentrated. You can usually tell if there are a lot of worms there because the ground will be uneven and the grass or plants may be yellowed.
Put on rubber gloves. Wait several minutes for the worms to surface. The worms will surface to get air. Pull the worms out of the ground by hand and place them in a bucket. Move the worms to a safer area of ground, or kill them. This method is best for smaller concentrations of worms.
Power rake the lawn to collapse some of the worm tunnels.
Fill a ballast roller one-third full with water and roll over the entire lawn to collapse some of the deeper tunnels.
Spread grub insecticide granules on the lawn in April and in October. Use 1.9 pounds of granules per 1,000 square feet of lawn. Use a fertilizer applicator to apply the insecticide to the lawn.
Water the lawn with 1/2 inch of water after applying the granules over the lawn. This should take about 30 minutes to an hour of watering.
Roll the lawn with the one-third full ballast roller while the lawn is still wet. This will destroy many of the worm's tunnels and also help smooth the lawn so that it is no longer uneven.