Cedar-Apple Rust

Are these galls harmful to the tree?

Hi Steve! I have moved this to fungi for you as the gall is caused by a fungus.

Great spot! A gall firework, primed and ready to go off! Now you know what you're looking at when it gets REALLY strange. Makita, I love your blog. Sounds like your kids are getting a great education.

Here's a more extensive explanation: http://pods.dasnr.okstate.edu/docushare/dsweb/Get/Document-1036/EPP-7611web.pdf You should link this to the Symbiotic Relationships Mission: http://www.projectnoah.org/missions/7987627

I think I found your answer: http://teapotshappen.com/2009/09/29/cedar-apple-rust-galls-coincidence/ We recently studied galls ourselves and wrote a post about it here: http://academiacelestia.blogspot.com/2012/02/galls-nature-study.html

Looks like some kind of Gall maybe?? Galls are out growths on trees caused by some kind of infection or parasite http://en.wikipedia.org/wiki/Gall