Insect identiification question - Ask Extension
Hi,
There are many of these very large flying insects on a young willow tree. They are probably about an inch long. It looks like they may be feedi...
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Insect identiification question #879034
Asked July 27, 2024, 4:23 PM EDT
Hi,
There are many of these very large flying insects on a young willow tree. They are probably about an inch long. It looks like they may be feeding on the willow tree because there are different wasps that i am guessing are eating sap or something like it based on this insect activity. I have tried to reseach what they are with no luck and trying to understand if they are harming the willow tree. Thank you.
Arapahoe County Colorado
Expert Response
Hi Steven,
The beetles in your photos appear to be Bumble Flower Beetles! The are harmless beetles. As adults, Bumble Flower Beetles prefer to feed on sweet things such as bacterial ooze from trees, overripe fruits, and/or pollen and nectar in flowers.
Since you are also seeing wasps visit the willows, it's possible that you have bacterial ooze (also called bacterial wetwood) or aphids on your willows. Aphids secrete a sweet substance called honey dew that attracts a wide variety of insects. Many beneficial insects also prey on aphids.
The insects in your photo are the adult beetles. It's possible you may come across the larvae or grubs in your landscape. Bumble Flower Beetle grubs are sometimes confused with Japanese beetles grubs, but they are two very distinct species. Both are C-shaped grubs, but you can determine which species of grub by the location. If you find grubs in a compost pile, garden bed, or any other location with high organic matter, you likely have Bumble Flower Beetle grubs. If you find grubs in your turf grass, you likely have Japanese beetles or other turf-feeding grub.
You likely don't need to take any action. If it is bacterial wetwood, symptoms can be exacerbated by drought. Keeping your willow and trees well-watered can help.
Aphids feed on plant fluids and can occasionally cause significant plant damage. If you start to notice a steep decline the health of the willows, you could consider using a hose or strong jet of water to hose down the plant. The impact will kill a lot aphids. If you aren't noticing anything significant, I would recommend leaving the aphids. They feed a lot of beneficial insects.
More information:
Thanks,
Lisa
Lisa Mason
Horticulture Specialist, Entomologist
Colorado State University Extension, Arapahoe County
The beetles in your photos appear to be Bumble Flower Beetles! The are harmless beetles. As adults, Bumble Flower Beetles prefer to feed on sweet things such as bacterial ooze from trees, overripe fruits, and/or pollen and nectar in flowers.
Since you are also seeing wasps visit the willows, it's possible that you have bacterial ooze (also called bacterial wetwood) or aphids on your willows. Aphids secrete a sweet substance called honey dew that attracts a wide variety of insects. Many beneficial insects also prey on aphids.
The insects in your photo are the adult beetles. It's possible you may come across the larvae or grubs in your landscape. Bumble Flower Beetle grubs are sometimes confused with Japanese beetles grubs, but they are two very distinct species. Both are C-shaped grubs, but you can determine which species of grub by the location. If you find grubs in a compost pile, garden bed, or any other location with high organic matter, you likely have Bumble Flower Beetle grubs. If you find grubs in your turf grass, you likely have Japanese beetles or other turf-feeding grub.
You likely don't need to take any action. If it is bacterial wetwood, symptoms can be exacerbated by drought. Keeping your willow and trees well-watered can help.
Aphids feed on plant fluids and can occasionally cause significant plant damage. If you start to notice a steep decline the health of the willows, you could consider using a hose or strong jet of water to hose down the plant. The impact will kill a lot aphids. If you aren't noticing anything significant, I would recommend leaving the aphids. They feed a lot of beneficial insects.
More information:
- Bumble Flower Beetles: https://webdoc.agsci.colostate.edu/bspm/arthropodsofcolorado/Bumble-Flower-Beetle1.pdf
- Bacterial wetwood: https://extension.colostate.edu/topic-areas/yard-garden/bacterial-wetwood-2-910/
- Aphids: https://extension.colostate.edu/topic-areas/insects/aphids-on-shade-trees-and-ornamentals-5-511/
Thanks,
Lisa
Lisa Mason
Horticulture Specialist, Entomologist
Colorado State University Extension, Arapahoe County
Thank you, Lisa!!!
