Horned oak galls are a relatively common sight on oak trees, but what are they and what do they do? Here's what you need to know about horned oak galls and how to deal with them.
What is a gall?
A gall is a small, round growth that can form on trees much like a tumor in humans. Galls are caused by a reaction to a chemical or physical injury. They are unsightly and may cause the tree to produce fewer leaves or fruit.
What is a horned oak gall?
A horned oak gall is a type of gall caused specifically by a horned oak gall wasp. The tiny wasp lays its eggs developing leaf buds. The interaction causes a gall to develop on the tree branch that soon envelopes the eggs, protecting the developing larvae from the elements and predators. When the larvae reach maturity, the wasp emerges from the gall and the process starts again.
What is the difference between a horned oak gall and a gouty oak gall?
While both the horned oak gall and the gouty oak gall are both abnormal growths caused by the same tiny wasp, they are different in appearance. The horned oak gall has actual horned growths that emerge from the gall as the larvae reach maturity. The gouty oak gall, on the other hand, has a smooth surface texture.
How do you treat horned oak gall?
There is no real treatment for horned oak gall as it does not really harm the tree. However, if the growth is unsightly, you can prune the branch that it is on to get rid of it. Furthermore, you can try to prevent the wasp from laying its eggs on the tree in the first place by spraying the tree with an insecticide or you can remove the galls as soon as you see them.
Do galls harm oak trees?
While a gall does not harm the tree itself, it can cut off nutrients to the infected branch. This may cause the branch to die. In addition, if a gall is large enough, it can weigh down and break the branch it is on.
Do squirrels eat oak galls?
Yes, squirrels are known to eat oak galls. In fact, they are one of the main predators of the wasp that causes the galls in the first place. By eating the gall, the squirrel gets rid of the wasp larvae before it has a chance to mature and emerge from the gall.
While horned oak galls may not cause any long-term damage to trees, they can be unsightly and lead to leaf loss. It is important to take care of the trees in your yard. When you notice horned oak galls or gouty oak galls on your trees, call an arborist for a closer look.
For more information about gouty or horned oak gall, contact a local tree service.