The vast majority of exclosures aren't experimental.They're done in areas with mainly poor habitat and they can't get desired regeneration until deer numbers are extremely low.That's a fact.I've walked through literally hundreds of exclosures and the vast majority of them get deer inside them on a regular basis.In fact,the older exclosures with electric fences had deer inside them pretty much all of the time.I've hunted hear these fences and have seen deer actually run between the wires.There's a hundred acre exclosure on Moshannon state forest not far from where I used to live.It was an old electric fence that was taken down about 5 years ago after being up for about 15 years.I consider it a failure because it's almost 100% red maple even though most of the overstory is oak.I used to bust my buddy's chops about it's failure because he's the district forester.He told me that the oak was doing well when they first cut it but enough deer got in,couple with a dry summer or two wiped out all the oak and gave the maple a chance to take over.I thought he was crazy until I looked at a differnt exclosure this past year that was a 70 acre shelterwood cut.It was cut a few years ago and two years ago the oak was regenerating beautifully.Three deer got in and literally wiped out ever small oak seedling and there was a visible browse line on every single stump sprout and every single sapling that was almost making it past the deer.The maple was slightly browsed but no where near the extent the oak was.Deer are picky and they eat the most prefered species first,altering the compostion of the forest.The problem gets magnified when the surrounding habitat is already poor because the deer key in on any new growth that's prefered.I had to see it to believe it but it's a fact.