I just noticed today that my little cactus seems to be sick. I'm not sure what kind of cactus it is. I've had it for two years and it's been fine so far. There's one big spot with what looks like a split in the skin of the cactus. There's a large area of sickly looking skin around that and up the side of the plant. On the other side the skin looks better except at the very bottom where there are some brown spots. Could this be over-watering? I recently moved to Pennsylvania (from Colorado) for the summer, so maybe it's something with humidity? Is there any way to save it? Should I repot it and let it dry? Someone please help!
I don't know how to help you. I think (not sure), but I think it's a Gymnocalycium. I had one that looked a lot like the one you have. Try taking it to a garden center that also deals with cacti. I found one in my area and that's who helped me. I wish I could do more. Good luck and best wishes.
Hope I'm not violating any rules of this site, but here is a site that may be able to help you. LOTS of cacti experts and enthusiasts. http://tech.groups.yahoo.com/group/Cacti_and_Succulents/
If the pot is damp and the air in your area is humid you want to repot is as soon as possible because it looks like you either have a fungus/mold problem or a bug problem. But the most common way to kill cactus is by giving it too much moisture. Even cutting them in half does not typically kill them. So whatever you do...do NOT water in the summer unless you absolutely must. Also if it is outside at the moment and you have been getting a lot of rain you might consider moving it inside.
The rule of thumb is to help people find the information they need (e.g., the list of links to other forums).
