bagworm

Common bagworms (family Psychidae) are so-named because the native moth caterpillars live in silk bags festooned with plant debris. It’s the perfect camouflage allowing them to remain undetected until their damage is revealed by their voracious appetites. The “bagworm season” is ending with the caterpillars transitioning from life in a tote bag to life in a sleeping bag.

Common bagworms have been with us for a while. Overwintered bagworm eggs began hatching in southwest Ohio at the end of May (see “Bagworm Eggs are Hatching: The Game’s Afoot!,” June 1, 2022). However, it’s amazing how long these general defoliators can continue to crawl below our radar as they chomp on evergreens and deciduous trees and shrubs before their cumulative damage and size finally make them apparent.

Look closely at trees and shrubs festooned with last season’s Common Bagworm (Thyridopteryx ephemeraeformis) bag-abodes. Overwintered bagworm eggs are hatching in southwest Ohio meaning the “bagworm season” is now underway.

Common bagworms (Thyridopteryx ephemeraeformis, family Psychidae) are native moth caterpillars that live in silk bags festooned with plant debris. It’s the perfect camouflage allowing them to remain undetected until revealed by their voracious appetites.

Overwintered common bagworm (Thyridopteryx ephemeraeformis) eggs are hatching in southwest Ohio. The 1st instar caterpillars are very small with their bags measuring around 1/8" in length.

This "bagworm season" which began in early June was marked by damaging localized infestations throughout Ohio. Images showing heavy defoliation from bagworms (Thyridopteryx ephemeraeformis) were commonly shared during our weekly BYGL Zoom Inservices. Populations appeared to be higher than has been seen for several years.

Overwintered common bagworm (Thyridopteryx ephemeraeformis) eggs are hatching in southwest Ohio. The 1st instar caterpillars are very small with their bags measuring around 1/8" in length.

Secrest Arboretum in late April and early May is a glorious sight to behold, from buckeyes to Crablandia, from sweetgum flowers to cedar rusts. Enjoy!

The vast majority of Common Bagworm caterpillars in southwest Ohio have initiated their annual "tie-off" in preparation for pupation. Bags are tightly closed and tied with silk to a twig or other anchorage point. Likewise, male bagworms in the northwest part of the state have tied-off; however, some female caterpillars are continuing to feed.

This is the time of the year when Common Bagworms come into clear focus owing to their size and noticeable damage. Overwintered eggs hatched in southwest Ohio in early June (see "Be Alert to Bagworms!" posted on June 6). However, it's amazing how well these native moth caterpillars crawl below our radar until their burgeoning appetites finally gives them away.