Answer: What's Wrong with this Plant? Oak Gall

I received only one answer for this plant mystery and yes, it is an oak gall.  Most galls do not harm plants.  They are usually caused by insects and the plant tries to defend itself from the pest.  To read more about Gambel Oak galls and how to treat them click here. I found this on the Utah Pest website.  It is a great resource for many pest problems along the Wasatch Front. 

Stay tuned and I will have many more plant problems for you to diagnose as the summer progresses.  Let's see if you know your stuff!