I have a development right behind our house kids run through my yard they mess with my stuff look in my shed people let there dog poop and there lanscAper ate apples off our apple tree are they required to have a fence around there proptery

No.
Looks like you will have to put up a fence, sorry. You can put up a big sign saying
NO TRESPASSING - VIOLATORS WILL BE PROSECUTED
but actually identifying people and taking them to court isn't easy, and it won't be easy to prove anything, unless you have video cameras going all day. And if that's not enough, you have to show actual monetary value of damages.

Nope, but you put up a fence or boundary markers with no trespassing signs. If you catch anyone entering your property, you call the police. If you can prove an employee of their's (landscaper?) ate your apples, you can sue for reimbursement.