Hairy Chinch Bugs in Lawns

Agdex#:	626
Publication Date:	04/08
Order#:	08-019
Last Reviewed:	08/09
History:	Replaces OMAFRA Factsheet Hairy Chinch Bugs in Lawns, Order No. 07-013
Written by:	P.M. Charbonneau - Turfgrass Specialist/OMAFRA; M.K. Sears - University of Guelph

PDF version - 7.87 MB

Introduction

Chinch bug is a destructive lawn pest in Ontario. First reported in 1971, chinch bug damage has since become a common home lawn problem in many provinces. Many lawns are only partially damaged, but in severe cases, the entire lawn can be damaged to such an extent that it must be entirely renovated.

Damage

Chinch bugs have piercing mouth parts. They suck the sap from the crown and stems of turfgrass plants. Populations of chinch bugs tend to be aggregated. As a result, the damage usually begins as lo-calized dead patches. These dead areas are brown, irregular, sunken patches, which can coalesce into larger dead areas (Figure 1). Chinch bugs thrive in hot, dry weather. Sunny areas are usually the most affected. All common turfgrass spe-cies in Ontario are susceptible to chinch bug feeding, but some varie-ties may be more susceptible to chinch bug injury. However, re-search has shown that turf cultivars containing high levels of endophytic fungi may show some re-sistance to chinch bug feeding.

Figure 1. Chinch bug damage on a lawn.

Figure 2. Adult hairy chinch bugs.

Description

The chinch bug causing damage to lawns in Ontario is the hairy chinch bug, Blissus leucopterus hirtus. This insect is quite small - the adults are 4 mm in length (Figure 2). The immature nymphs are bright red in colour when they first hatch, and begin to darken from brick red to grey/brown when they are nearly mature. The imma-ture nymphs have a characteristic white band across their abdomen, which is eventually covered by the enlarging wings as the insects become larger and mature (Figure 3).

Figure 3. Chinch bug nymph with white band across the abdomen (far right).

Life History

The adult chinch bug spends the winter congregated under trees and shrubs and on the edges of lawns under hedges and in flower beds. As the temperatures become warmer in the spring (mid- to late May), the adults move into the lawn and begin depositing eggs.

The first young nymphs can be found in late May to early June; these individuals be-come adults by mid-July in the Guelph area. Damage is usually ap-parent by the middle to end of July. In most of Ontario, severe damage is not noticed until August, after several weeks of hot, dry weather.

Detection

Use one of the following methods to confirm a suspected chinch bug infestation:

Method I (Figure 4)

• Make a cylinder by cutting out the bottom and the top of a large can (approx. 200 cm in diameter).
• Force the cylinder into the turf.
• Fill the cylinder with water. Any chinch bugs present will soon float to the surface of the water.

Figure 4. Method I for detecting chinch bugs.

Method II (Figure 5)

• Fill a bucket with water.
• Place a 4 cm x 4 cm square of lawn or a golf course cup changer plug (10 cm diameter) into the bucket.
• Wait several minutes for the chinch bugs to float to the top.
  

On a lawn that has little or no damage, take ten of these samples throughout the entire lawn. On lawns where damage is visible, take samples in the healthy grass near the dead patches. If the lawn has more than 20 chinch bugs per cylin-der or if roughly 10 chinch bugs are found with the bucket method, damage is likely to occur.

Figure 5. Method II for detecting chinch bugs.

Timing

The best time to check for chinch bug infestations is the second week of July in the Guelph area or when the bird's foot trefoil is in full bloom (Figure 6). (This will vary from year to year and from one lo-cality to another.) At this time, most eggs have hatched, and the initial stages of damage are mini-mal.

Figure 6. Bird's foot trefoil in full bloom.

Cultural Control

Irrigated lawns are more able to tolerate chinch bug feeding without damage occurring.

Research has shown that turf cultivars containing high levels of endophytic fungi may show some resistance to chinch bug feeding.

Resources

OMAFRA Publication 384, Turfgrass Production Recommendations.

This Factsheet was written by Pam Charbonneau, Turfgrass Specialist, Economic Development Division, OMAFRA, Guelph, and M.K. Sears, Department of Environmental Biology, University of Guelph.