Can a Power co. that has a ROW thru the property from one side to the other cut accross land not in the ROW

The last time they maintained their ROW by cutting trees and brush they drove equipment thru my woods because it was easier than staying within their ROW at either end. The result was damaging trees and creating another access point into my property.

It depends on if the power company has easement or a right of way. If it's a right of way, then probably not unless you gave them permission to do so (and with everything, it should be in WRITING). If it's an easement, there's probably something in that contract or deed that says they have the right to reasonable use of property. However, they should be responsible for damage if they're doing so. Contact the power company and find a copy of the ROW agreement.