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Billbugs: Don't Let Them Overtake Your Lawn!

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Golf Course Lawn Disease I recently attended a two-day conference, The 2016 National Turf Grass Entomology Workshop and Pollinator Summit. Both days were very interesting and enlightening. The first day was spent reviewing the work of Entomologists from 16 universities across the US. I found it very interesting as we have franchises in the state where most of the universities are located or in a nearby state. There are several new insect pests attacking turf in some parts of the US. Most of the work that these Entomologists do is based around golf courses as the environment can be controlled easier than on a residential lawn.

How to Identify Billbugs - Expert Lawn Care Tips


One of these turfgrass pests I had never heard of before is called a Sugar Cane Beetle. It is a scarab beetle and the larval stage is a white grub, similar to the traditional white grubs we see feeding on lawns and this species has developed a taste for the roots of St. Augustine Grass along with sugar cane. Two other “new” insect pests that were discussed are the Seed Corn Beetle and the Carrot Beetle.  The Carrot Beetle is a cousin of the Sugar Cane Beetle. It is unknown if the Sugar Cane Beetle problem reported in Kansas City was a one-time occurrence or the development of a new pest. The one insect that was discussed the most was different species of Billbugs.

Four main species of Billbugs.

  1. Bluegrass Billbug
  2. Hunting Billbug
  3. Denver Billbug
  4. Phoenix Billbug.
Another species of the weevils is the Annual Bluegrass Weevil, which is more of a golf course pest than of home lawns. Billbugs are the most misdiagnosed turfgrass pest because their damage is often confused with drought damage. The adult, which has a large snout or proboscis, does feed on the grass blades, but only causes minor damage.
  • *Fun fact: When they are located in the turf, they often play possum and lay still for a while until they feel the danger has passed.
The females lay eggs in small cavities that they chew in the stem of the grass plant. The larvae hatch and start feeding inside the stem and into the crown of the plant, which kills the plant. They also feed on roots and rhizomes in the soil. The larvae are small, about 1/8 of an inch long, white, lack legs and have a reddish head.

Billbug larvae causing lawn diseases

Since the damage may not be noticed until after they are done feeding, identification requires following a process called the “tug test.” When an individual plant is pulled and it easy lifts from the surface, it is a good indicator that Billbugs have been present. By carefully observing the base of the plant that was pulled up, you can often observe hollow stems and what appears to be small grains of sand. This is the frass or Billbug droppings left from their feeding.

roots of a plant - billbug damage

If you think your lawn may have had a problem with Billbugs, contact your neighborhood Spring-Green office to have it check. There are control measures that can be taken to reduce the damage that these tiny grubs can cause and we can put together a program to help your lawn recover.