Looks like a gall on an oak tree....is that an oak?
Caused by an insect....does the tree no harm. Enjoy it aas an oddity.
Linda C

How intriguing! The first thing I thought was that it looked like an old man with a huge nose--and his head was surrounded by a wreath!

Hey, I think the heat is getting to me--and I'm not even going outside.

One of my apple trees, has several of those. We planted the tree about 35 years ago. One growth started about 15 years ago and now it has several.
Until this post I had no idea what they were and did not they had a name (gall). It is still growing apples.

That would be called a burl. These examples of hyper-growth can be caused by insect damage, disease, even physical injury. In most cases, burls don't cause the tree any problems and are certainly never a reason to cut the tree down. They are not 'contagious'.

You'll be interested in knowing that some skilled woodworkers covet burls! They go into woods looking for them and will even make contracts arborists and other tree workers to notify them when a nice burl comes their way. Hand-made burlwood bowls can be stunning.

Galls are also an example of hyper-growth, but are always insect or mite created and typically found on twigs, smaller woody stems, and leaves. Galls are typically much smaller and not located on the trunk.

Sometimes, these insect galls crop up in large numbers on trees, depending on the activity of the particular critter causing the galls.

Whilst not a problem the burl makes a very beautiful veneer and is great for turning bowls. That is, if it's a hardwood tree.

I took some picks of the many gall/burl on my appletree and posted one of them in the "gallery".
I'd be interested in knowing what it is?
Anyone?

I have seen many in the tree work I have done over the years and have some in my special wood pile out back. As noted in the wiki below they can be caused by insects, viruses, fungus or injury. Usually the burl does not affect the health of the tree unless it impairs the flow of nutrients in the cambium. The one on your apple tree looks like it could be due to insects or a virus.

For a year or so when I came home from the service I worked for a custom office furniture company. There was an old timer there that I learned some from. We did leather inlays and burled wood inlays with burled veneers that were very expensive pieces and very beautiful. I have given some to a neighbor that turns bowls nd his work is very nice also.

Here in So Cal we have California Pepper trees that get burls at the base on most of them and sprout suckers from the a lot. Removing the suckers on a regular basis creates burls of many sizes. You can see the bud bases that are cut off in the burls and cutting through shows the wood grain you see on the dash boards of expensive cars.

The Pepper wood is not a hard wood so they do not last as well as some others. Olive trees will do the same and get the suckers at the base with constant removal creating a burl. Olive is a very pretty oily wood and I have some pieces. So some are even man made in an off hand way.

Here is a link that might be useful: Wiki on burls with pictures