Deer and Wildlife Fencing

Why this matters

Deer-exclusion fencing is the single most-requested specialty fence in rural and suburban-edge markets. Customers spend thousands on landscaping that a herd of whitetail will clear in three nights. Get the height wrong by 6 inches and the deer still jump. Get the bottom gap wrong by an inch and deer push under. Get the corner posts under-spec and the entire fence sags in two seasons. Wildlife-exclusion fencing is one of the few fence types where the wrong specification is functionally a complete failure, not a partial one. A 7-foot fence that lets one deer in is the same as no fence at all because that one deer ate the hostas. The fence has to be right.

What you are excluding

Whitetail deer: Adult bucks can jump 8 feet from a standstill. From a running approach, recorded jumps clear 10 feet. The species standard for exclusion is a fence high enough to discourage the attempt, not high enough to physically stop the jump. 7 to 8 feet vertical is the standard recommendation; 6 feet works in some terrain but fails in others.

Mule deer: Comparable to whitetail. 8 foot fences recommended.

Elk: Larger, stronger, and able to break through wire fences that would stop deer. Elk-rated fence is 8 foot woven wire with heavy posts at close spacing. The Rocky Mountain Elk Foundation publishes specifications.

Moose: Largest cervid; specialty problem in moose country (Maine, Minnesota, Alaska, Wyoming). Moose will simply walk through or over most fences. Moose exclusion is rare in residential work; usually a property-fencing issue handled with wide buffer zones rather than a perimeter fence.

Black bear: Bears do not jump fences; they climb or push through. Exclusion requires electrified strands at bear chest height. Many "wildlife fences" in bear country are layered: deer fence plus electric strand.

Coyote, raccoon, fox: Smaller predators that dig under fences or climb over chain link. Exclusion adds buried wire mesh (12 to 18 inch dig deterrent) and either an over-hang at the top or a roller-bar (Coyote Roller brand).

Establish the target species with the homeowner. The fence design changes substantially per species.

Mesh, height, and post systems

For deer-only residential exclusion, three system categories cover almost every job:

Polypropylene mesh deer fence (Benner's, Tenax, Deerbusters): 6 to 8 foot tall black polypropylene mesh with 1.5 to 2 inch openings, tensioned between fiberglass or steel rod posts at 15 to 20 foot spacing. Visually disappears at 30 feet (the black mesh against woods reads as shadow). Cheapest deer-exclusion solution. Lifespan 10 to 15 years before UV degrades the mesh. Easy to repair (cable-tie a patch).

Woven wire deer fence (Red Brand, Stay-Tuff): 8 foot tall woven wire (typically 1949-12.5 or similar pattern, 12-1/2 gauge wire, graduated openings tightest at the bottom), tensioned between treated wood posts or steel T-posts at 16 to 20 foot spacing with corner H-braces. Lifespan 20 to 30 years. More visible than polypropylene; more durable. Standard for orchards and high-value horticulture.

Welded wire deer fence: 8 foot tall welded wire panels (typically 2 inch x 4 inch openings, 14 gauge wire), set between wood or steel posts. Mid-tier in cost and durability. Common in vegetable garden enclosures where the rigid panel is desirable.

Electrified high-tensile (Gallagher, Premier): Multi-strand 12.5 gauge high-tensile smooth wire on insulated posts, charged by a fence energizer. 5 to 8 strands at varying heights. Used in agricultural deer exclusion where extreme deer pressure overwhelms passive fencing. Requires energizer, ground rods, periodic vegetation clearance from the wire. Not common in residential.

The bottom gap problem

Deer push UNDER fences as readily as they jump over. A 4 inch gap at the bottom of a deer fence on uneven terrain is a deer-sized opening over time as the deer enlarges it nightly.

Three solutions:

Stake the bottom tight to grade with 8 to 12 inch landscape staples (galvanized rebar bent into U-shapes) every 4 to 6 feet. Standard for polypropylene mesh fences.

Run a tension wire at grade through the bottom mesh openings, tightened to wood corner posts. The wire holds the mesh tight to grade across small dips.

Bury the bottom 6 to 12 inches in a trench. Most durable, most labor. The right answer where the customer is excluding raccoons, foxes, or coyotes as well as deer.

In any case, walk the entire bottom line on day 30 and again on day 90 after install. The first sign of deer pushing through shows up as a depressed mesh and tracks; address before the dog-sized hole becomes a deer-sized hole.

Corner and end posts

The deer fence load is dominated by perimeter tension. Line posts (along the run) see lateral wind load only. Corner posts and end posts (where the fence terminates or changes direction) carry the tension of every wire and mesh stretched between corners.

Standard residential corner: 5 inch nominal pressure-treated wood post (UC4B per AWPA U1) set 4 feet deep in concrete, with an H-brace assembly to a second post 8 feet inside the corner line. The H-brace transfers the tension to a second-post compression load, holding the corner against pull.

H-brace assembly: two posts, a horizontal compression brace (typically a 2x4 or a 4 inch top rail) notched into the posts at top, and a diagonal tension wire (12 gauge galvanized) running from the bottom of the corner post to the top of the brace post, twisted to tension with a stick.

Skipping the H-brace on a long-run deer fence is a guarantee of a leaning corner within 18 months. The brace is not optional.

Visibility and ribbon tape

Deer are crepuscular and have poor visual acuity at the fence's low contrast. A clean black mesh fence in dim light is essentially invisible to a deer running through woods at dusk. The first deer to hit the fence dies of broken neck OR breaks the fence; both are bad outcomes.

Mitigation: tie white 1 inch polypropylene ribbon (sold as "fence flag tape" or just farm flagging) at intervals along the top wire of the fence. Every 10 to 20 feet along the upper edge gives the deer a visual cue they can avoid.

Standard for the first 90 days after install; thereafter the deer have learned the fence is there and the ribbon can be removed if the homeowner objects to the look.

Gates

References

• AWPA U1 Use Category Standard (UC4A and UC4B treated wood for ground-contact posts)
• ASTM A641 Standard Specification for Zinc-Coated (Galvanized) Carbon Steel Wire
• USDA APHIS Wildlife Damage Management Technical Series: Deer (deer behavior, exclusion strategies)
• Cornell Cooperative Extension Deer Damage Control Guide (regional adaptation of exclusion practices)
• Tenax Deer Fence Installation Guide current edition
• Red Brand Fence Installation Guide for High Tensile Woven Wire current edition