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Problem Identification

Who's who in your garden? It is essential to identify pests correctly in order to make decisions on control measures. Use a 10X handheld magnifying glass to examine symptoms of damage possibly caused by disease or insects.

Pests & Beneficial Organisms

Beneficial insects and related small creatures inhabit turf and function as defenders of plants. Some, such as springtail and millipedes, feed on plant debris or fungi and are quite harmless. Pill bugs and spiders are also friends not foes. They defend gardens and lawns from harmful insects and diseases, so resist the temptation to squash these creatures.

Earthworms may seem like a nuisance when their burrows disrupt smoothness and uniformity, however, they play an important role by aerating and enriching soil, improving water filtration and breaking down thatch.

Other pests are voracious predators or parasites which can cause damage either as eggs or in their various stages of development.

Some lawn problems are not related to insects or small animals. Dehydration, cutting the grass too short, over-watering and abuse from foot traffic can all cause lawns to become unsightly. Consider adding stones or mulch over heavy traffic areas of your lawn and be sure to mow the grass with a sharp lawnmower blade, leaving the blades of grass about 6 - 8 cm tall.


Once an infestation has occurred which causes an immediate or potential risk of substantial loss or damage, methods of dealing with the pest can be put into practice. Options include manual removal of the pest, removal of the plant, biological & alternative products. See Factsheets & Links for information on the different types of infestation in your lawn or garden and how to control them.

  • Manual (mechanical) removal of pest

This could include such things as flyswatters, hot water, picking bugs off plants, cutting off diseased branches, manual weeding, etc. While it is time-consuming, manual removal of pests is by far the most “environmentally friendly” solution.

  • Removal of plant

If leaving the plant risks spreading disease, unsuitable for the climate or invasive, you may decide to simply remove it, preventing pesticide use and the costs associated with it. Faced with the need to replace the plant, try to pick a cultivar (type of a plant bred for specific qualities) based on use, growth environment (for example, soil type, light availability, moisture availability), the desired appearance, the maintenance it requires and its resistance to pests. Native plants are often good for this, as they have evolved along with the pests commonly found in the area. Some cultivars of perennial ryegrass and tall fescue have been found to be associated with fungi known as Endophytes. Insects such as sod webworms, chinch bugs and billbugs find these fungi undesirable and may feed less on these cultivars.

  • Biological & alternative product solutions

Some biological solutions include the release of predatory bugs or nematodes, or Bt (Bacillus thuringiensis, a bacterium which produces a protein toxic to certain insect species). The availability of these biological solutions is currently limited in Canada. Alternative product solutions having relatively low toxicity include mineral oils, DT (diatomaceous earth, which is essentially ground up fossils), insecticidal soap and borax.  


Monitoring determines the presence and activity of a pest before turf loss occurs. This is usually accomplished by visual inspection and may include some of the insect monitoring techniques described below. The frequency of monitoring is determined by the homeowner; however, once per week is usually sufficient.

It is difficult to know precisely when to begin and finish monitoring turf. On average, if regular monitoring is conducted between May and September, it will be adequate. This is not intended to be a hard and fast rule - dates will change depending on how early or late spring and fall begin. Other important factors include the life cycles of turf insects, diseases and weather conditions which favour disease and insect development.

Here are two simple insect monitoring techniques using everyday household items such as a coffee can or dishwashing soap.

  • Coffee can

This technique is useful with Hairy Chinch Bugs. Take a 20 cm to 25 cm (8 to 9 inch) diameter coffee can. Remove the top and bottom. Insert the can into the soil to a depth of 3 to 5 cm (1 to 2 inches). Fill with water. Count the number of chinch bugs that float to the surface in 5 to 15 minutes. You may have to refill the can with water more than once during this period. If 20 or more chinch bugs are present, then some form of treatment may be needed.

  • Soap solution technique

This technique is effective for caterpillars such as the sod webworm and black cutworm. Make a soap solution using 30 ml (2 tablespoons) of liquid dishwashing soap in 8 litres (2 gallons) of water. Pour over a 1 m2 (10 square foot) area of turf.  This forces caterpillars to the surface within 5 minutes.


Following treatment, it is important to evaluate the success of the treatment. Take notes to remind yourself in the future of exactly what worked and what didn’t.  You can find additional information on preventing and controlling all types of pests under Factsheets & Links.

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