chewed leaf Western Tent Caterpillar Update



Are tent caterpillars poisonous? Generally no. The hairs on the tent caterpillar can be irritating. Animals (and children) may react adversely if caterpillars are eaten (eating tent caterpillars is not recommended). Back East in Kentucky, there is a phenomenon occurring right now known as Mare Reproductive Loss Syndrome. Kentucky has been experiencing an unusual amount of abortion by mares (female horses). It is related to an outbreak of eastern tent caterpillars. I do not believe we currently have to worry about this in Whatcom County. To learn more about this, click here.

Will tent caterpillars kill my trees? Established trees can handle at least 25% defoliation without experiencing any ill effects. Tent caterpillars may need to be managed if on very small, newly planted trees. Successive years of heavy infestation may harm small, susceptible trees. Visit the Tent Caterpillar Management section of this web site to learn more.

If I have a problem this year, can I expect a problem next year? Not necessarily. Tent caterpillar 'outbreaks' are cyclical. Year-to-year population sizes are dependant on weather, climate, food and natural enemies. Often tent caterpillar populations will dramatically decrease after an 'outbreak' year. To see the cyclical nature of tent caterpillars, visit British Columbia's forestry pages to see an animated map of western tent caterpillar populations since 1937!

Is a torch or flamer good to use to kill tent caterpillars? NEVER use fire to manage tent caterpillars or any other pest! Fire is dangerous, uncontrollable and unpredictable. More damage can be caused by fire than tent caterpillars could ever cause, so the risk in using fire is not worth it. Almost every year that tent caterpillars are common, someone damages property or themselves when using fire to burn the tents. Visit the Tent Caterpillar Management section to see safe, effective and easier forms of management.

Feel free to contact us with your questions and concerns.

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