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Got a question for Ask MDC? Send it to AskMDC@mdc.mo.gov or call 573-522-4115, ext. 3848.

Q: I saw a barred owl on the edge of our woods. We have about 12 acres of forest behind our house. Would an owl house be a good idea?

Barred owls reside along forested streams, lakes, rivers, and swamps, particularly in deep woods with big timber. They forage at night, and often even during the day. But when large trees are removed or downed, these cavity nesters miss out on opportunities for quality habitat.

Erecting a nesting box can help attract a breeding pair to your neighborhood. Make sure you put it up well before breeding season, which begins in earnest in March. Attach a guard to keep predators from raiding eggs and young. It’s best for the box to be about 12–15 feet high, attached to either a live tree or a post. And barred owls are more likely to use the box if it is within 200 feet of water.

Once a breeding pair has identified and occupied the space, expect to see two or three round, white eggs. The incubation period will last 28 days, and the owlets are reared for 42 days.

Although this owl is not often seen, its classic series of hoots is commonly heard and easily identifiable as sounding like the phrase, Who cooks for you, who cooks for you all?

To find out more about how to correctly build and place a box, visit short.mdc.mo.gov/4Zm.

Q: I found these on the sunny side of a juniper. What insect makes these?

These were made by evergreen bagworm moth caterpillars. These caterpillars create their cases, or “bags,” using silk and bits of plant foliage. The caterpillars drag these cases around as they feed and eventually will secure the bag to a branch or other solid structure to pupate.

Although named the evergreen bagworm, these caterpillars feed on a variety of trees and shrubs, including deciduous trees. Normally bagworms are covered in juniper clippings, but they’ll attach clippings of whatever plant they’re feeding on. You might look around in your flower beds or on nearby plants for more bagworms. To see what bagworms look like when they’ve fed on deciduous plants, visit short.mdc.mo.gov/4Zs.

Eggs hatch in late spring and tiny caterpillars can move to new plants by throwing out a silk thread into the wind, which is called “ballooning.” Once whisked to a new plant — sometimes far away — they start to build their new bags almost immediately. They remain mobile while they are feeding, carrying their bags like hermit crabs carry their shells. Female moths are wingless and don’t leave their bags; male moths can fly and do leave their bags to mate with females. Eggs are laid in the bags.

Bagworms can be a pest of both native and ornamental evergreens. Not only can they strip native eastern red cedars in natural locations to the point the cedars die, but they also can harm the ornamental junipers in your yard. If you have shrubs or trees with large numbers of bagworm cases, you may want to remove these cases to help reduce the number of caterpillars present this summer.

They are overwintering in the egg part of their lifecycle now. Since they are not feeding, insecticidal treatments are ineffective. But bagworms can be hand-picked off plants and disposed of in a garbage bag or thrown in a bucket of soapy water. For more information on bagworms, visit short.mdc.mo.gov/4Ze.