Tuesday, March 06, 2007

Eastern Gall Rust



I took this picture in April 2005 but only recently figured out what it was. When looking up something else I ran across a photo of Eastern Gall Rust (Cronartium quercuum). It's similar to the Cedar Apple Rust that I wrote about last year. They are both heteroecious, which means that they require two unrelated hosts to complete the life cycle.

I learned that $10 word from the Rust page on James Worrall's excellent Forest Pathology site, where you can also learn about cankers and wilts and so many other problems that you'll be amazed that trees can survive at all.

According to one site, the portion of the tree beyond the gall normally dies, which I suppose explains why I haven't noticed this gall since the spring I took this picture.

11 comments:

James Cooper said...

Interesting, it's sort of like a fungally-induced tree tumor. Mostly a problem in nurseries though, so it seems the fungal spores don't spread very well in the wild.

The heteroecious nature is definitely the most fascinating aspect of the infection though. Really amazing how these things evolve.

Cathy said...

Those pictures from last April are terrific. I've never seen anything like this and I'm a bit of a fungus aficionado (check out my latest post). The rotten world around us is fascinating and I love learning new 10 dollar words. Thanks!

Rachel said...

Eeeeweee!!! Looks kind of gross, like little gold worms are on it or something. Fungi is fascinating and there are so many different kinds. Truly amazing!

Floridacracker said...

Is that solid like a burl?

Ontario Wanderer said...

Thanks for sharing both your photo and the Forest Pathology site. I look forward to even more interesting information!

thingfish23 said...

And welcome back.

KFarmer said...

You find the most interesting things! Thanks for sharing :)

Hope all is well with you and yours!

PS- I found my copy of The Bad Back book and the offer still stands if you want me to send it to you -just let me know :)

Laurie said...

Very interesting post. I hope your back is better. I've missed you.

KFarmer said...

Yes, his name is Jerry Wayne and its a small book but very informative. I wish you as much luck and success as I've had with his exercises :)

Rurality said...

Thanks everybody.

FC, I think it was solid, but I didn't, umm, probe it a lot.

KF, it's ordered now!

KFarmer said...

Wonderful!! :)