A deer fence is a specialized exclusion barrier designed to protect cultivated areas, such as gardens, orchards, and agricultural fields, from the destructive impact of browsing ungulates. Unlike traditional property boundaries, this type of fencing must account for the unique athleticism and behavioral patterns of the animals it is intended to exclude. The efficacy of the system relies on creating a barrier that the deer perceive as an impassable obstacle, either physically or psychologically.
Defining Characteristics and Purpose
A deer fence differs from standard fencing by prioritizing deterrence over simple structural containment. Deer are highly wary animals that rely on a wide field of vision to assess threats, meaning a successful fence functions as a psychological impediment as much as a physical one. The fence presents an obstacle that deer are unwilling to risk attempting to cross, especially if their line of sight is disrupted. Deer are cautious of new objects placed in their familiar routes. The primary function of a deer fence is exclusion, which dictates its design specifications.
The Critical Role of Fence Height
The vertical dimension is the most important factor of an effective deer fence. White-tailed deer, the most common species in North America, possess remarkable jumping capabilities, clearing heights of 7 feet or more when highly motivated or startled. Standard 4-foot or 6-foot fences, while common for residential boundaries, are easily breached by a determined or pressured deer. To reliably prevent intrusion under routine deer pressure, the minimum effective height for a physical barrier is 7.5 to 8 feet.
This height is necessary because it disrupts the deer’s ability to safely judge their landing zone on the other side. Deer are hesitant to attempt a jump if they cannot clearly see where they will land, as a leg injury significantly reduces their chance of survival. Alternative height strategies can achieve the same deterrence without the full vertical structure. For instance, creating a three-dimensional barrier, such as a double fence line spaced a few feet apart, confuses the deer’s poor depth perception.
Similarly, a multi-strand electric fence angled outward at a 45-degree pitch exploits their reluctance to jump an unstable or complex barrier. These designs leverage the animal’s behavior to make the barrier seem far more complex.
Material Types and System Approaches
Deer exclusion systems utilize several material types, each offering a different balance of visibility, durability, and cost.
Woven Wire Fencing
Woven wire fencing, often constructed of high-tensile galvanized steel, offers the greatest strength and longevity, frequently lasting 20 years or more. This material provides a solid barrier that is resistant to charging or pressure from large animals. However, metal wire is generally more expensive and can be highly visible in the landscape unless coated in a dark, less reflective material.
Polypropylene Mesh
Polypropylene mesh, a lightweight plastic netting, is a cost-effective and low-visibility option that blends easily into the environment. While simpler and cheaper to install, it is less durable than metal and is vulnerable to tears, necessitating a product with a high breaking load, such as 800 pounds, to withstand deer contact. The plastic mesh often requires a “skirt” of metal hexagrid fencing along the bottom to prevent smaller animals from creating entry points that deer can later exploit.
Electric Fences
Electric fences operate primarily as a psychological deterrent through the delivery of a mild shock upon contact. These systems are less visually obtrusive and simpler to install than full physical barriers, often utilizing only a few strands of wire or polytape. The success of an electric barrier relies on maintaining a constant, adequate charge, as a deer that tests the fence and receives no negative stimulus will quickly learn to ignore it.
Installation Fundamentals and Longevity
The effectiveness of the entire system hinges on adherence to installation fundamentals. Gaps or weak spots in the perimeter render the full vertical height irrelevant, as deer will test the boundaries for the easiest path. It is important to secure the bottom edge of the fence tightly to the ground to prevent deer from crawling underneath. Adequate tensioning is necessary for the fence to maintain its intended height and structure across the span between posts. Rigid materials require posts to be spaced appropriately, such as a maximum of 8 feet apart, to prevent sagging that reduces the functional height.
Longevity requires routine maintenance, including checking the perimeter for tears or breaches and ensuring that the electrical charge in hot-wire systems remains consistent. Corner posts must be robustly anchored and sized, often requiring a 4-inch diameter or greater for high fences, to withstand the tension and environmental pressure that can compromise the barrier over time.