Site Protection: Fence Before You Plant

Why One Season of Grazing Undoes Years of Work

A young tree seedling is, from the perspective of a deer, rabbit, goat, or cow, an extremely attractive food item. It is soft, nutritious, accessible, and often the greenest thing on a degraded site. A single browsing event that removes the growing tip of a seedling can set it back by a full year of growth. Repeated browsing kills it outright or traps it in a stunted, shrubby form that never develops into a canopy tree. On sites with heavy browsing pressure, seedling mortality from herbivory routinely exceeds seventy percent, rendering even well-designed reforestation projects futile.

The arithmetic is brutal. A restoration project that spends thousands on site preparation, nursery-raised seedlings, planting labour, and post-planting care can have its entire investment erased in a single season by uncontrolled grazing. A flock of sheep on a hillside restoration site for one week during spring, when seedlings are flushing with soft new growth, can browse every planted tree on the site. Deer, which are selective browsers preferring broad-leaved species over grasses, disproportionately target the native hardwoods that are typically the most valuable components of a restoration planting.

This is not a theoretical risk. It is the single most common cause of restoration failure worldwide. Tony Rinaudo's farmer-managed natural regeneration technique in the Sahel succeeded precisely because it addressed browsing first: farmers agreed to protect regenerating tree stumps from livestock and fire, and the trees grew. Decades of tree-planting projects in the same region had failed because planted seedlings were browsed to death within their first dry season. The trees were never the problem. The browsing was.

Fencing Options

Permanent fencing is the most reliable method of excluding large herbivores from a restoration site. For deer, a fence needs to be at least 1.8 metres high, and on sites with high deer pressure, 2.0 metres or more is advisable. Standard stock fencing of 1.2 metres excludes cattle and sheep but not deer. The choice of fencing material depends on budget, site access, and expected lifespan. Steel post-and-wire fencing is durable, lasting twenty to thirty years, but expensive and labour-intensive to install on steep or rocky terrain. Wooden post-and-rail fencing is attractive and sturdy but even more expensive.

Electric fencing offers a cheaper, more flexible alternative. A well-maintained electric fence with adequate voltage deters deer, livestock, and in some configurations, rabbits. Electric fencing can be installed quickly, repositioned as the restoration site expands, and removed once trees have grown beyond the reach of browsers. The disadvantage is maintenance: electric fences require regular checking, vegetation must be cleared from the wire to prevent shorting, and a reliable power source (mains, battery, or solar) must be maintained. On remote sites, solar-powered energisers are increasingly affordable and practical.

Individual tree guards, plastic tubes or wire cages around each seedling, are an alternative to site-wide fencing on small sites or where fencing is impractical. Spiral guards protect against rabbit bark stripping. Tubular tree shelters, typically 1.2 to 1.8 metres tall, protect against deer and also create a microclimate that accelerates early growth. The cost per tree is significant, but on sites where only a few hundred trees are planted, individual protection may be cheaper than perimeter fencing. On larger sites, the cost of guarding every tree individually quickly exceeds the cost of fencing the entire area.

Managing Browsing Pressure

Fencing is only as effective as its maintenance. A fence with a single gap is no fence at all. Schedule regular fence inspections, particularly after storms that may have brought down trees onto the fence line, and repair damage immediately. Deer will find a gap within days and learn to return to it. On sites with very high deer populations, consider supplementary measures inside the fence: scent deterrents, sacrificial planting of species deer prefer (to draw pressure away from target trees), or night-time surveillance during peak browsing seasons.

Rabbit control requires different approaches. Rabbits dig under or squeeze through fences that would exclude larger animals. Rabbit-proof fencing requires a mesh of no more than thirty millimetres, buried at least 150 millimetres below ground and turned outward at the base to prevent burrowing. On sites where rabbit-proof fencing is impractical, individual spiral guards on every seedling are the minimum defence. Where rabbit populations are very high, population management through professional control may be necessary before planting can succeed.

In landscapes where livestock grazing is an integral part of the local economy and culture, simply fencing off land for restoration can generate conflict with farming communities. Negotiation and compromise are essential. Community engagement from the earliest planning stage, involving herders and livestock owners in the restoration design, creates the social licence without which fencing will be vandalised and gates left open. Offering alternative grazing, providing improved pasture on unfenced land, or incorporating controlled grazing into the restoration management plan as a tool for grass suppression are all strategies that align restoration goals with livelihood needs.

When to Reintroduce Controlled Grazing

Permanent exclusion of all herbivores is not the goal of most restoration projects. Grazing is a natural ecological process, and many ecosystems depend on it to maintain their structure and diversity. The question is not whether to graze but when and how much.

As a general rule, grazing can be reintroduced once planted trees have grown beyond the reach of the target herbivore. For cattle and sheep, this typically means a stem diameter of at least eight to ten centimetres and a height of two metres or more, which takes five to ten years depending on species and growing conditions. For deer, trees need to be taller and sturdier still. Reintroduce grazing gradually, at low stocking rates for short periods, and monitor the impact on tree survival and regeneration before increasing intensity.

Conservation grazing, the deliberate use of livestock to manage vegetation structure for ecological benefit, is a valuable tool in many restoration contexts. Cattle grazing at low density in a restored woodland creates a mosaic of grazed and ungrazed patches, maintains open glades that support pollinator habitat, and prevents grass from suppressing new tree regeneration. The key is control: stocking rate, timing, and duration must be precisely managed. Uncontrolled or year-round grazing will degrade the site you worked so hard to restore. Seasonal pulse grazing, short periods of moderate intensity followed by long rest periods, mimics the movement of wild herds and produces the best ecological outcomes.

Site Protection: Fence Before You Plant

Why One Season of Grazing Undoes Years of Work

Fencing Options

Managing Browsing Pressure

When to Reintroduce Controlled Grazing

See Also