Deer can jump an 8 foot fence if they want to, I have seen them jum 6 ft fences standing flat footed next to the fence. No white strand of anything on top of a fence will keep deer from jumping a fence. Lots of myths out there that are nonsense and a waste of time. One thing that does work is what is called the Penn State deer deterrent fence, it is a 5 strand electrified fence. While it is not 8 or ten or even 6 feet high, deer will dry to crawl under or through a strand fence and they will get a good shock and not try it again, they are used successfully in PA and the PGC provides them to farmers to protect certain crops. you can call this number and ask the PGC to send you the plans to erect the fence, 717-787-4250. Ask for the Bureau of wildlife protection and ask whoever you are connected to for the fence plans to be sent to you.