Live oak galls from Terry , Louisiana

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This plant was found in the woodlands about 30 miles north of Baton Rouge , La. I am sorry for having just this one picture…..I did not visit your site prior to discovering the plant and had no knowledge of the requirements. Any information will be deeply appreciated.


your plant is a branch from a live oak tree, Quercus virginiana, with wasp insect galls on it.  I found the following on the Internet at  :

“The “ball shaped growths” on your Live Oak are called galls.  The most common Live Oak gall in North Central Texas is a brown sphere about the size of a quarter.  You are correct in that these woody growths are caused by a wasp.  However, this wasp is no larger than a fruit fly.  It “stings” plant tissue and injects a hormone that coaxes the tree to grow a chamber for one or more wasp eggs.  Within months, the egg hatches into a small grub that soon matures into a wasp.  Eventually the wasp leaves the gall structure through the exit hole that is apparent on most older galls.

This brown woody gall is commonly found on Live Oak trees in North Central Texas.

While this gall is woody and persistent, anchoring to the specific stem for years, it presents no significant health issue for the tree.   Why some trees can be heavily infested and others virtually untouched is a mystery to plant pathologists.  However, the wide diversity in oak species genetics is believed to play into the phenomenon.  Gall infestations do tend to run in cycles, just as other insect populations do.


There may be other factors causing the two trees to not grow the same.  Water and fertilize both trees regularly and have a certified arborist inspect the tree if it fails to respond positively.”


Steve Hill, Botanist, SCNPS


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