Ground is hard no matter how you look at it. Trees are harder. Which one do you wanna smack?

If you ride, you WILL crash. The best advice I can give is to get quality gear, and try to not ride out of your level. Try both MX and trails to see what you like. Both are a blast. The main thing is NOT to ride above your level. When you get passed by a faster person, its good to try to follow them and learn their lines, but don't get the adrenaline rush and try to pass them back. It will come, just don't force it cuz probability of crashing will go up quite a bit.

Anyway, I'd rather land on the downside of a groomed jump than smack a tree. Trees can take out Cadillacs, think what they can do to 230 lb. bikes. And as someone mentioned above, the DO move. The jump out in front of me all the time.