Is American Arborvitae (Thuja, Emerald Green) deer resistant?

Browsed to a distinct line as high as a deer can reach, and a leading cause of ruined privacy screens.

This is the damage that does not recover. Arborvitae will not resprout from bare wood, so once the lower three or four feet have been stripped the plant stays bare there permanently. A hedge planted for screening ends up screening nothing below head height, which is exactly where it was needed.

Do not plant it unprotected in deer country. If it is already in and being browsed, netting or fencing through the winter is the only thing that stops it, because winter is when the damage happens.

Green Giant is often sold as the deer-resistant alternative. It is browsed noticeably less than American arborvitae but it is not immune, and under real pressure it will still take a browse line.

Do deer eat arborvitae?

Yes, and it is the worst-rated conifer on the Rutgers list. American arborvitae is Frequently Severely Damaged, the bottom tier, "American Arborvitae, Thuja occidentalis, Trees, D," in the company of hostas and yews. NC State: "Damage from deer browsing can be a serious problem," and the same entry records that white-tailed deer "both feed on the branches and use them for shelter from the cold," which is the whole problem in a sentence. The hedge planted for winter screening is where deer spend the winter. The damage is done from November to March, at the height a deer can reach, and it is a browse line rather than a nibble.

Which arborvitae is deer resistant?

None of them, on the evidence, but they are not equal. Rutgers rates Western arborvitae, Thuja plicata, one tier better, Occasionally Severely Damaged, and Green Giant is a hybrid of T. plicata and T. standishii. Nothing consulted here rates the hybrid on its own, so the claim that Green Giant is deer-resistant rests on one parent's C rather than on a trial of Green Giant. One tier better than the worst is still a plant that gets browsed.

Protecting arborvitae

A screen that matters gets a fence or a wrap for the winter, every winter, and over the years the arithmetic favors the fence: in the VerCauteren trials a 1.5 meter fence stopped none of the deer, 2.1 meters stopped 85 percent and 2.4 meters, about 8 feet, all of them. Burlap or netting on a frame from November to April does the same for a young hedge one season at a time. Repellent works on a small planting: Colorado State's 20 percent egg spray is rated High, reapplied at about thirty days, which through a winter means five applications in weather that does not encourage it.

If it is browsed

This is the plant where recovery depends on something hard to see. Iowa State's answer to whether stripped arborvitae green back up: "If buds are present, the lower branches will produce new growth in spring. The new growth should be apparent by early summer." And the other case: "The lower portions of the arborvitae will remain bare and likely never develop new growth if no buds are present." A hedge that has reached the second case is replaced, or underplanted with an evergreen deer leave alone, Japanese plum yew being one that gives the same mass in shade.