I HOME  |   II BIOLOGY  |  III MONITORING  |  IV FACTORS  |  V PERMITTED MATERIALS
VI CONTROL: Overview  Acute  Cultural  Redesign
VII GUIDELINES  |  VIII PHOTOS  |  IX REFERENCES
QG CHINCH NOW

www.versicolor.ca/lawns

Control of Chinch Bug Without Pesticides
and Other Ecological Lawncare Practices

   III. MONITORING
    CHINCH BUG
  1. When to Look
  2. Where to Look
  3. Exposing Chinch
  4. Close Examination
  5. How Many Chinch Bugs
    Are Too Many?
  6. In a Nutshell
  7. Links

  • Use FRAMES  for easy navigation
  • SITE MAP
  • SEARCH this site
  • Telltale eggs and nymphs in thatch

    A resident or property manager may want to look for chinch bugs in order to anticipate possible damage later in the season, or to confirm that patches of dying grass observed in July and August are due to chinch bug. Monitoring is an essential part of a progam for control of chinch at sites where it has caused damage in previous years. The monitoring process is largely a matter of keeping an eye out for early signs of possible damage by chinch and confirming that chinch bugs are present in large numbers at the margins of the affected area.

    1. When to Look

    In HRM, be on the lookout by July 1. Being watchful at least one to two weeks earlier than July 1 may be advisable if spring and early summer are exceptionally warm, or in warmer, inland regions.

    Development time of chinch bug is temperature dependent. Growing degree-days, which can be calculated from commonly available climatic data, are commonly used as a predictor of development times. Chinch bug/growing degree-day relationships have been reported for Ontario, Quebec and, recently, by Wellwood et al.[C4] for several municipalities in New Brunswick. In the that study, numbers of second and third instar nymphs peaked between mid-July and mid-August. Based on growing degree-days for normal years, they recommended monitoring for chinch bugs from July 1 to mid-August for Rothesay, Bathurst and Moncton, and slightly earlier for Fredericton. Growing degree days for HRM are close to those for Rothesay.

    The first dates are approximately two weeks before the first pesticide control decisions are advised by Wellwood et al.[C4] under an IPM system. The control times (mid July to mid-August for Rothesay and inferred for HRM) correspond to peak 2nd and 3rd instar populations. Applying control treatments at this stage is considered to be optimal because all eggs have hatched and the early stage nymphs are more susceptible to treatment and less mobile than later stages.[C1]

    The monitoring and control dates advised by Wellwood et al.[C4] related to use of pesticides under an IPM system*. However, they are also relevant to use of alternative treatments (Section V) under a pesticide-free system as in HRM. The message: start looking by July 1, or earlier if spring and early summer are exceptionally warm, or in warmer, inland regions.


    IPM refers to 'Integrated Pest Management'. It is often promoted as an alternative to pesticide bans. However, while it is in principle it sought to reduce pesticide use, under IPM practiced by most of the lawncare industry, it is not attempted to eliminate their use and it is acknowledged that in some instances, use might even be increased. This sort of IPM cannot be regarded as a step in a transiton to complete elimination of pesticides, as sometimes seems to be implied. The term 'Biointensive IPM' is used to describe IPM that makes use of only soft pesticides, and emphasizes cultural control of pests first and foremost. (See www.attra.org/attra-pub/ipm.html for more on Biointensive IPM.)

    2. Where to Look

    In scientific studies, and in some monitoring programs in which counts of chinch are made before there are any visible signs of damage, random sampling may be necessary or advised. (Random sampling means not prejudging where to look).

    Otherwise, on large properties one should look preferentially or give priority to looking in areas that are prone to drying out (drier, full sun areas, especially on south facing slopes, mounds, edges of turfs and the sides of buildings where heat is radiated)[C1, L3] especially if they had chinch in previous years. (On smaller properties, it's pretty easy to survey the whole lawn.)


    Possible early chinch bug damage on an exposed slope near the curb. Click on image for larger version.
    Look for early signs of damage, i.e. patches of yellowing grass or patches of yellowing grass with brown grass in the centre (See II: BIOLOGY 4. Appearance of Damaged Grass). Then look within those patches for chinch bugs. The best place to look is at the junction between the dying grass and green grass, which is where they will be concentrated (if the damage is due to chinch). Chinch bugs are most active in the mornings, especially on hot days.

    3. Exposing Chinch

    There are two general approaches: observation of chinch bugs in place, and observation after physical removal of chinch bugs. [C1-C5; C10-15]

    A. Direct Observation


    Looking for chinch bugs
    Get on your hands and knees, part the grass and look for chinch bugs near the base of plants and on the soil and on or in thatch. A magnifying glass may be helpful.[C17] Look quickly as the chinch bugs will hide when the ground is moved or the grass is parted. Earlier chinch stages are less mobile than later stages; Although they are very small - not much more than a millimeter - they are bright red and easily observed.

    A variant on the direct observation technique is to add soapy water first:[C11]
    Chinch bugs can also be detected by sprinkling 1/4 cup of lemon-scented household detergent mixed in two gallons of water over one square yard of turf and counting the insects as they crawl to the surface.
    Here's another version:[C16]
    Use 4 to 6 ounces of liquid soap in 5 gallons of water and pour on a 4 square foot area to check for soil insects [such] as mole crickets. Slowly slide your foot through the sod and water; chinch bugs crawl across your shoe if they are present.

    B. Physical Removal

    Two techniques — flotation and the soap and flannel sheet trap — are commonly cited. Congdon and Buss[C9] suggest use of a vacuum cleaner.
    Using the flotation technique to look for chinch in a chronically stressed area of The Oaks Experiments.[C6]

    Flotation. Flotation techniques are used in formal, quantitative surveys of chinch populations.[C1] Many documents describe a coffee can procedure for home use. The following version incorporates suggestions and comments from many sources.[C1-C5; C10-15]

    Cut out both ends of a large can, such as a large coffee can.

    Place the can over the junction between dying and green grass and work it into the soil. If there is heavy thatch, it may be necessary to cut into the soil around the edges of the can with a sharp knife. Use heavy gloves to press it in, turning it as you do so. Placing a short board over the top of the can and pressing on the board will help distribute the pressure evenly. Insert it to at least 5 cm (2 inches), and compact the soil around the edges for better sealing.

    Fill the can with water, carefully, so as not to dislodge a lot of clippings and debris. Chinch bugs begin to float to the surface within a few minutes. Five to ten minutes are required for most of the bugs to come to the surface; refilling may be necessary.

    The chinch bugs can be collected with a small brush and some conserved in alcohol (rum, vodka, gin will do) for later examination, or the numbers counted or estimated without removal (once you know what you are looking for). Mole crickets are also brought up by this procedure, and big-eyed bugs which superficially resemble chinch.

    A variant on this procedure is to take out a sample of turf and submerge it:[C10]

    ....using a hole cutter, remove a sample of turf and soil, place it into a bucket, and slowly add warm water to the top of the grass blades. Let the soil and turf core soak for several minutes, and then count the number of insects that emerge.

    Soap and flannel sheet trap

    Health Canada[C13] describes this technique as follows.

    A small area of lawn (approx. 50 x 50 cm) is drenched with a soapy solution (30 mL of dishwater soap in 7 liters of water) and covered with a flannel sheet for 15 minutes; chinch crawl onto the sheet, where they can be inspected (and vacuumed or rinsed off).

    Vacuuming

    As a less labor-intensive option, Congdon and Buss [C9] suggest the following:
    Use a Dust Buster or hand-held vacuum cleaner to suck up any chinch bugs near damaged areas. Remove the filter, dump the contents on the sidewalk, and look for nymphs and adults. Repeat in several damaged areas.

    4. Close Examination to Confirm Chinch


    Young nymphs, bright red with a white band across the middle, are tiny but not difficult to see.
    A hand lens or magnifying glass may be needed initially to see the characteristic features on chinch bugs (See II BIOLOGY 3. Appearance of Chinch Bug for further description and photos of chinch bug.) The earlier stage nymphs are reddish with a white band in the middle; the adults have whitish or silvery wings and a characteristic cross hatched appearance. Don't expect many adults until early August or later.[C4] Don't confuse chinch bugs with big-eyed bugs, which prey on chinch bugs. Big-eyed bugs are of similar size, but have big eyes and different patterns on their backs. Both types of bugs, but not most other types of insects, stink when mashed between fingers.

    5. How Many Chinch Bugs Are Too Many?

    It depends on grass health and broadleaf cover.

    First it depends on how the chinch bugs are being observed. Flotation techniques are used in scientific studies to determine the total numbers of chinch. However, they are not practical for routine monitoring. Wellwood et al.[C4] calibrated a direct observation technique against numbers determined by flotation.[C4] They observed chinch bugs in quadrats of 0.1 m2 area (slightly more than 30 cm x 30 cm or 1 foot by 1 foot), which took an average of only 3 minutes versus 17 for the flotation technique. The numbers revealed by the flotation technique were approximately 10 fold those revealed by the quadrat technique.

    Secondly, it depends on the health of the turf and the broadleaf cover. The surveys in New Brunswick[C4] indicated that below a count of 10 chinch bugs per 0.1 m2 in a 60 second search (by experienced observers) no damage was likely. Above 10 chinch bugs per 0.1 m2, damage was possible, but depended on the general health of the turf or on broadleaf cover.

    Neighborhood Watch

    Here's a thought. Students might take an interest in monitoring chinch bugs to develop their biology skills or to earn some money as neighborhood 'chinch bug patrol officers'. For a full science fair project, one might look at the abundance of chinch bugs and natural enemies in different situations or under different experimental treatments.

    Presence of broadleaf cover is especially significant. Wellwood et al.[C4] noted that "lawns with higher populations of broadleaf plants (weeds) ~10% showed less visible damage from chinch bug feeding than lawns with fewer weeds despite above threshold HCB populations." (HCB refers to hairy chinch bug.) Weeds in their definition would include white clover, which if allowed to proliferate can amount to over 40% of the cover in July.[L25]

    Wellwood et al.[C4]describe undamaged turf with 10 chinch bugs per 0.1 m2 or more (by direct observation) as 'hotspots' of chinch activity. With experience, they say that it takes less than one minute to determine whether the numbers of chinch in a quadrat are above ten.

    Because of the importance of turf health and broadleaf cover in determining whether hot spots of activity actually damage the turf, they advise NOT to treat such areas immediately. Instead, they advise re-examining the hotspots at weekly intervals, and treating them only if damage is actually observed.

    In practice, this procedure is very similar to keeping an eye out for early signs of possible damage by chinch bugs, and confirming (or not) by direct observation that chinch bugs are present in high numbers at the junction of damaged and undamaged areas.

    6. In a Nutshell

    It's not really very complicated.

    Start looking out for early signs of damage - small patches of dying grass - by early July, paying special attention to areas prone to dying out. This could be done before mowing each week, or by just generally keeping an eye out for damage when using the lawn. Get on your hands and knees and, part the grass in the region of the junction of dying and healthy grass, and look for high concentrations of chinch bugs. In the early stages of damage, these will consist mostly of bright red nymphs; later there will be many winged adults which scatter quickly. Pouring some dilute soap solution over the patch will slow them down. Compare abundance at the junction with numbers in adjacent healthy grass. Examine more patches if chinch bugs aren't found in the first one. If the damage is due to chinch, you will find chinch bugs; if it isn't, you won't find them, or you will find only a few and not more than in healthy grass. Initially, you might take a little extra time to become familiar with chinch bugs, perhaps collecting some by flotation or other techniques, or using a magnifying glass.

    If you are dealing with an area that had been heavily damaged by chinch in previous years, it could be examined for chinch before there is obvious damage, e.g., to assess whether changes in cultural practices (Section VI) seem to be working.

    Links

    • UNL Entomology - Turfgrass Insects - Chinch Bugs (http://entomology.unl.edu/turfent/documnts/chinchbg.htm) University of Nebraska Department of Entomology. Spons, F. Baxendale. Project leader. (Viewed 18 Mar. 2005)
      Good photograph of chinch bugs at different stages, coffee can technique.

    • Hairy chinch bug survey, demonstration and monitoring in New Brunswick, 2002. (Abstract ) (http://www.gnb.ca/0389/2001-2002/038920020005-e.asp) New Brunswick Agriculture, Fisheries and Aquaculture and New Brunswick Horticultural Trades Association, Spons., A. Wellwood, G. Nickerson and J. Wetmore, Auths. (2003. Viewed 16 May 2007)
      The full document, which was accessible via the New Brunswick Horticultural Trades Association website until recently, provides many details about development and monitoring of chinch bugs in our region. Unfortunately, it is no longer available via that route. However, Chapter 7 in the NBTA's Sustainable Turf Manual provides some information about chinch bug drawn from that publication.

    Top of Page

    I HOME  |   II BIOLOGY  |  III MONITORING  |  IV FACTORS  |  V PERMITTED MATERIALS
    VI CONTROL: Overview  Acute  Cultural  Redesign
    VII GUIDELINES  |  VIII PHOTOS  |  IX REFERENCES
    QG CHINCH NOW


    Site posted 5 Apr. 2004
    This page posted 12 Apr. 2004
    Page modified 16 May 2007.