Hairy Chinch Bugs in Lawns
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Table of Contents
- Introduction
- Damage
- Description
- Life History
- Detection
- Timing
- Cultural Control
- Resources
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
localized 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 species in Ontario
are susceptible to chinch bug feeding, but some varieties may be
more susceptible to chinch bug injury. However, research has shown
that turf cultivars containing high levels of endophytic fungi may
show some resistance 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 immature 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 become adults by mid-July in the Guelph area.
Damage is usually apparent 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:
- Make a cylinder by cutting out the bottom and the top of a large
can (approx. 20 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.
- 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 cylinder 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 locality to another.) At this time,
most eggs have hatched, and the initial stages of damage are minimal.
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
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.