Eew! what is this Dahlia tubber doing?!!!!!!!

What IS this?!!!!!

it looks like the eye is going berserk. i tried to grow these in pots some of them rotted these are the survivors.

What is the consistency of the "warty" thing? Is it soft, hard, do the warts crumble off? Looks like the rest of the tuber is healthy, no? Weeeeiiiirrrrrrddd....Just in time for Halloween-Frankentuber? Tuber of Terror? Were-tuber?

I think it's called "gall". Annie - come to the rescue!

While they're not quite like that, I did note some strange growth at the base of some tubers when digging. These had a mass of growth just above soil level, a mass of tiny stems and leaves in a tight wad. I have a feeling they would have looked like that before they sprouted above the soil surface.

Indeed I think it's either crown gall or fasciation of the eye/crown, not sure. Looks impressive for Halloween!

I've only seen the multiple lobed mass-like growth on one plant. I grew it in a pot with success but did not save the tubers off it.
Can't find a photo easily, but look around and you may have some luck.
http://www.bioimages.org.uk/html/t149583.htm
http://www.ipm.ucdavis.edu/PMG/GARDEN/FLOWERS/DISEASE/crowngall.html

It is pretty firm. I wonder if dahlias grown in wet conditions get this disease. it looks like a mass a leaves and stems before they sprout like too many little stems trying to grow all at once. I'm trying to figure out it this is a disease that will spread to other tubers or if i can try to save this one by breaking of this overgrowth - i guess would best describe it.

crown gall or fasciation of the eye! Both sound like they could be it. what does that mean? What do I do now?

Wonderearth, If you save healthy looking tubers off that clump, I'd plant it/them in a pot in 2010 just to keep it/them isolated from any other dahlias. Grow them next year and see how the tuber clump looks at that time.

I spoke to a grower about this a couple years ago and they can't risk any disease in their fields so they would toss it in the trash, not compost. That would be the safest bet by far.

I tossed it and the plant that was growing with it. It was just tooo extreme. Pretty sure its the fasciation of the eye thing.