The Forestry Forum
General Forestry => Tree, Plant and Wood I.D. => Topic started by: sprucebunny on December 13, 2004, 07:37:15 PM
I think this is called an oak gall but don't remember what causes them.
(https://forestryforum.com/images/03_21_04/oakgall.jpg)
not sure, but I think it is caused by insects? LeeB
You're right!
A wasp stings the plant and causes it to create wild growing cells. Eggs are layed in the gall and the insect larvae eats the inside until mature enough to emerge and do his thing on the outside.
Sprucebunney it is caused by insect ,cut it in two an explore you will find tiny worm dead center of the star.Have fun Mtn Jack
Here's an earlier thread Tom started last spring (https://forestryforum.com/cgi-bin/board/YaBB.pl?board=tree_id;action=display;num=1084142265)
Here in California where there are lots of different oaks, there are about ~60 different gall wasps. Some of the galls are big and round like the photo, others look like star fish, muffins, brown cotton balls, etc. Quite amazing the first time you see them.
Ray