Bug FAQCreosote Bush Bagworm
Thyridopteryx meadii · Order: Lepidoptera · Family: Psychidae
Source: Wikipedia
The creosote bush bagworm builds a 30-40 mm bag from leaf or twig pieces of its host plant and lives inside it for most of its life. Males leave the bag as winged moths with translucent white wings and a long black furry body, while females stay larval inside the bag. It occurs throughout the Mojave Desert wherever creosote bushes grow, recorded in California, Texas, Arizona and Utah.
Source: Wikipedia
How to recognize it
Females keep a larval appearance and remain inside their bag after pupation.
Source: Wikipedia
Size
The bag they construct measures about 30 to 40 mm in length.
Source: Wikipedia
Is it a pest in the house?
By defoliating creosote bushes, they can reduce the health and appearance of these desert shrubs.
Source: Wikipedia
Where it lives
It lives throughout the Mojave Desert wherever creosote bushes are found.
Source: Wikipedia
What it eats
The larvae feed on creosote bushes and are the main cause of flower death on these plants.
Source: Wikipedia
Life cycle
The whole life cycle can finish in a few weeks under good conditions, but larvae may stay dormant for a year. They survive long droughts and cold winters as larvae or eggs sealed inside the bag.
Source: Wikipedia
When you see it
They are most active during the late-summer monsoon period. Activity is triggered by rainfall that produces soft new growth on the host plant.
Source: Wikipedia
Where it comes from
It is a North American species that specializes on the creosote bush. Its range includes California, Texas, Arizona and Utah.
Source: Wikipedia
Where it is found in the US
Recorded in 6 of 51 states and DC. Most records: Nevada, California, Texas, Arizona, New Mexico, Utah.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
Status: native in North America; native in United States. Source: iNaturalist
Months it is reported in the US
Source: GBIF
More photos
Questions people ask
What plants does the creosote bush bagworm damage?
It feeds on creosote bushes and causes the flowers to die.
Source: Wikipedia
When are creosote bush bagworms most active?
They are most active in the late summer monsoon and after rain that softens new growth.
Source: Wikipedia
How can I tell male and female bagworms apart?
Males leave the bag as moths with white wings and a black furry body, while females stay inside the bag looking like larvae.
Source: Wikipedia
Same family (Psychidae)
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Thyridopteryx_meadii
Look it up elsewhere: GBIF · iNaturalist · BugGuide · Wikipedia
Text written 2026-10-27 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-27.