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Trees/Identify substance found below Oak Trees


I have sever places in my yard where there are piles of golden colored granules, that appear to be hopping around.  At first I thought it was fleas but I sprayed it with bug spray and they still continued to hop around.  I keep finding new piles of this and when I walk around the neighborhood I see more of it.  I started noticing that above all the piles there is an oak tree branch hanging.  I live in a condominium complex and we have lots of oak trees and they are not very well maintained.  Do you have any idea what this is.  I took a picture but am unable to scan it to my computer to attach.  This stuff looks a little like birdseed with color ranging from dark gold to very light gold.  I would appreciate an expert opinion as to what this is.

Sounds like minute wasps called Jumping gall wasps. Here is a web link to information about these unusual insects. Like most gall insects they eggs on the leaf and the cells of the leaf expend over the egg forming a gal. They do not really effect the health of the tree.

The galls are actually malformations of plant growth. The tiny gall-forming wasp lays an egg in an oak leaf at a precise moment in the tree’s growth cycle, causing normal plant cells to multiply at an unusually high rate. As a result, the tiny egg becomes encased in the gall composed of oak leaf tissue.

When the egg hatches, the gall provides both food and a living chamber for the larvae. In summer, the oak gall drops to the ground with the tiny wasp larvae inside. The insect moves in jerks, causing the entire gall to jump around on the ground. It’s believed that the larvae hop around in an attempt to find a crack in the soil to hide up in. At maturity it transforms into a pupae, and later into an adult which chews its way out of the gall. The wasps themselves are dark colored, so tiny that you’ll probably never see them, and harmless to people.

Jumping oak galls almost never cause tree death. Natural enemies drastically reduce the population of this pest after a year or two, so control measures are unnecessary.

At times, these galls can become so numerous that they cause discoloration of the oak leaves and even premature loss of leaves. Yet, they do not affect the health or vigor of infested trees. Only expect jumping oak galls to be found for a year or two in any location, so be sure to enjoy these marvels when you find them.

Here is a web link to more information on this insect.  


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Jim Hyland


I am an expert in Forestry, Forest Entomology, Forest Pest Control, and Forest Health. Extensive knowledge in Identification of insects and diseases of trees. Expert on Bark beetles and other insects that attack forests. Also a Registrated Forester with extensive knowledge in the management and care of forests.


34 years as State Pest Management Chief in a Southern state. Extensive knowledge in Forestry.

BS with major in Forest Management and Entomology
Registered Forester
Certified Pesticide Appicator

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