Gall Wasps: What Homeowners Need to Know

Posted by Matthew Rathbone on February 14, 2023 · 2 mins read

Are you seeing small bumps on the leaves of your plants? These bumps could be caused by gall wasps. Here’s what you need to know about these tiny insects.

DIY Wasp removal recommendations

For non aggressive wasps I've had great luck spraying the nests with this Spectracide wasp remover in the evening. For more aggressive wasps I also use this rediculous looking upper torso Beekeeping suit. It seems silly, but trust me, it's amazing.

What are Gall Wasps?

Gall wasps are small insects that typically measure less than 1/8 inch in length. They’re often found on oak trees, but they can also affect other types of plants. Female gall wasps lay their eggs on the leaves or stems of trees or plants. When the eggs hatch, the larvae burrow into the plant tissue, causing a growth called a gall.

Are Gall Wasps Harmful?

In most cases, gall wasps are not harmful to the overall health of the plant. The galls may look unsightly, but they don’t usually cause significant harm. However, if your plant is already stressed or weakened, the presence of gall wasps could further damage it.

How Can You Control Gall Wasps?

If you’re concerned about the appearance of galls on your plants, there are a few things you can do to control gall wasps:

  • Prune affected branches: If the infestation is limited to a specific branch, you can prune it off and dispose of it.
  • Use beneficial insects: Some beneficial insects, such as parasitic wasps, will attack and kill gall wasps.
  • Apply insecticides: Insecticides can be effective in controlling gall wasps, but be sure to read the label carefully and follow all instructions.


If you see small bumps on the leaves or stems of your plants, they may be caused by gall wasps. While these insects aren’t harmful in most cases, they can be unsightly. By pruning affected branches, using beneficial insects, or applying insecticides, you can keep these pests under control and ensure the health of your plants.