European Crane Fly Control and Lawn Care Alaska Region Did you know? + Using some pesticides, such as diazinon and chlorpyrifos (Dursban), to control crane fly larvae may cause bird kills. + Use of such pesticides has caused bird kills in Sitka, AK, Seattle, WA, and other parts of the western U.S. and Canada. + More than 100 species of birds are known to feed on crane fly larvae. + Pesticides are not necessary to reduce crane fly populations. Pesticide use to control European following spring. Cold winters with little crane fly larvae in lawns has resulted snow cover can result in heavy larvae in migratory bird deaths in Southeast mortality. Besides the damage done to Alaska and other coastal communities lawns by crane fly larvae, birds, such in the western U.S. and Canada. In as ravens, may feed on the larvae, and an attempt to prevent additional bird through digging and pecking, the birds deaths, we are providing the following also may cause significant damage to information to homeowners who lawns. maintain lawns. In May-June, leatherjackets stop European Crane Fly feeding, make a cocoon and become The European crane fly, Tipula pupae. In July-August, the pupae paludosa, is a species not native to emerge as adults, and within 24 hours the United States. It is an introduced the adults swarm, breed and die after Adult European crane flies look like species that feeds on grass roots and laying between 200 to 500 eggs in grass. mosquitoes, but neither feed nor sting can be a pest in turf. Other crane fly (total length can be over 4 inches). Ken species are native to the U.S., and these Gray, courtesy of Oregon State University insects are not considered threats to lawns. In fact, they serve a beneficial Lawns with less than 15 larvae per role by speeding the decomposition of square foot need no control. When organic matter. greater than 25 larvae per square foot are present, control is recommended The crane fly life cycle spans because turf damage is likely to occur. approximately one year with the At 55 crane fly larvae per square foot, following life stages: egg - larva - pupa - control is essential to maintain a healthy adult. The larval stage is the longest in lawn. Several options exist for control the life cycle and lasts approximately 10 of crane fly larvae, including biological months. European crane fly larva - leatherjacket control organisms, organic pesticides and synthetic pesticides. However, the European crane fly larvae often are (can be over 1 inch long). Ken Gray, courtesy best strategy for controlling European called leatherjackets because of their of Oregon State University crane flies is to maintain healthy turf. thick, greyish colored skin. They hatch How to Determine Larvae Numbers in late summer and cause damage to Crane fly outbreaks are not consistent Maintain Healthy Turf grass by feeding on grass roots and from year to year. If European crane fly Generally, European crane flies are stems through the winter and into the larvae are suspected to be present in a found in greater numbers in poorly lawn, the homeowner can monitor the established, unhealthy turf. The best insect population in the turf starting in strategy for controlling European crane early April. flies is to maintain healthy turf. Soil and water management, as well as selecting Select 4 to 5 locations scattered grass varieties such as fescue and throughout the lawn and cut 6-inch by bluegrass that are adapted to the local 6-inch squares about 1 to 2 inches deep. environment, are critical elements for Remove the cut pieces and soak each healthy lawns. piece in mild soapy water. This will cause the larvae to float to the surface. Manage Soil pH Count the number of larvae present Test the soil pH in the fall, and at that in the piece of turf and multiply the time, add agricultural or dolomite lime European crane fly eggs (approximately number by 4 to give the number of as needed to achieve a soil pH between 1 mm long). Ken Gray, courtesy of Oregon State larvae per square foot. University 6.0 and 6.5. Never apply quick lime to surface to incorporate back into the be registered for home lawn care after lawns or gardens. lawn. December 2001, and diazinon no longer will be registered for home lawn use after 2004. Soil Fertility Management Alternative Landscaping These insecticides are very toxic to birds, Manage soil fertility by applying a There are alternatives to lawns and documented bird kills from these balanced nutrient source consisting of including ground covers that use products have been reported in Sitka, AK, nitrogen, phosphorus and potassium either native plants or other Seattle, WA, and other parts of the U.S. (N-P-K). These nutrients are most easily landscaping species, low-growing and Canada. Additionally, both of these obtained in the form of a slow-release shrubs and ferns. pesticides are known to be toxic to fish and fertilizer that is applied in May and other aquatic organisms. again in late August. Do not apply Biological Control Organisms when soil temperatures are below 55ºF. Biological control uses living Pesticide alternatives to Dursban and Organic nutrient sources should be microorganisms, such as nematodes, diazinon to control crane flies are limited. applied in the fall to slowly decompose to attack the crane flies. Nematodes Alternatives include restricted use over the winter. are microscopic worm-like creatures. pesticides, which only can be applied While some nematodes are considered by a certified applicator, or general use While the amount of fertilizer applied to be pests, many nematode species insecticides known to kill bees and other will vary according to the source and attack and feed on soil-dwelling beneficial and non-target organisms, such ratio of the nutrients, approximately organisms, such as crane fly larvae. as fish. Always be sure the crane fly larvae 3 pounds of actual N-P-K should be For the most effective control of population exceeds 45 per square foot of applied per 1,000 square feet per year. crane flies in cool spring soils, look turf before considering pesticide use, and Always read and follow the fertilizer for a product containing either do not use pesticides in late summer. manufacturer’s instructions. Improperly Heterorhabditis (sp.) or the cold- applied fertilizer can pollute streams hardy strains of Steinernema (sp.) If Using Pesticides: and actually damage the grass. nematode. These species usually + require soil temperatures above 55˚F Always read and follow the pesticide Mulching lawn mowers are and moist conditions. Nematodes are label for proper mixture and application recommended. These mowers chop the living organisms which must be procedures. The label must specifically clippings into small pieces, which will handled carefully and applied at the allow the use of the pesticide on slowly decompose and add nutrients right environmental conditions or residential lawns. back into the lawn. Keep in mind that they will die. + Southeast Alaska’s cool, wet summers Never exceed the pesticide application will greatly slow the decomposition of Pesticides rate, as listed on the pesticide label. such clippings. Pesticides are products used to kill, + If a granular form of the pesticide is control or mitigate pests and are used, it should be watered immediately to Thatch is the buildup of clippings, dead registered by the U.S. Environmental surface roots and other organic debris. prevent birds from ingesting the Protection Agency (EPA). In the granules. This will impede soil drainage and past, pesticide application was reduce adequate soil fertility. Thatch often the first recommended control + Never use micro-encapsulated pesticides can be removed by using a hand or strategy for pest management. on lawns. mechanical thatcher in the spring or We now know that pesticides may early fall. Thatching also increases soil contaminate the environment, kill aeration. beneficial organisms that attack Water Management the pest and even kill non-target Grass roots need oxygen to enable organisms, such as birds. It is against uptake of water and nutrients. In federal law, as enforced by the EPA, Southeast Alaska, excessive soil water and state law, as enforced by the in lawns can be managed by subsurface Alaska Department of Environmental drainage. Applying a top-dressing of Conservation, to allow a pesticide to sand and improving drainage around injure or kill non-target organisms, the perimeter of the lawn will also assist including birds and fish. in soil drainage. Mechanical aeration Two pesticides previously registered of lawns by plugging the turf assists European crane fly adult (not to scale). for use to control European crane fly Courtesy of Oregon State University in both soil aeration and soil nutrient larvae are diazinon and chlorpyrifos movement. Turf plugs can be left on the (Dursban). Dursban no longer will U.S. Fish & Wildlife Service For more information please contact: Visit the Contaminant Program home page at: 1 800/344 WILD Deborah Rudis http://alaska.fws.gov/fisheries/contaminants/ http://www.fws.gov U.S. Fish & Wildlife Service index.htm 3000 Vintage Boulvard #201 Juneau, Alaska 99801 July 2001 907/586 7648 [email protected] or Bob Gorman Alaska Cooperative Extension University of Alaska Fairbanks 907/786 6323 or toll free 1 877/482 3223 .