Tree Lines and Fence Placement — Tips for Shaded Runs

Trees and fences have a complicated relationship. Shade is great for stock, tree lines make natural property boundaries, and mature eucalypts look brilliant along a well-built fence line. But trees also drop branches, grow roots that push pickets out, and create ongoing maintenance headaches if you don't plan your fence placement carefully.

THE BENEFITS OF FENCING NEAR TREES

Before we get into the challenges, there are genuine reasons to run fences along tree lines:

Stock welfare: Fences along tree lines create shaded paddock boundaries. Stock gravitate toward shade in summer, and having the fence in the shade zone means they're loitering along the fence rather than in the middle of the paddock. This reduces fence pressure because they're resting, not trying to get through.

Natural boundaries: Property boundaries often follow tree lines, creek vegetation, or remnant bush corridors. You may not have a choice — the fence goes where the boundary is.

Environmental compliance: Many properties have vegetation management obligations that require fencing off remnant vegetation or riparian zones. These fences by definition run through or alongside trees.

THE CHALLENGES

Falling branches: This is the big one. Eucalypts drop branches — it's what they do. A fallen branch on a mesh fence can push pickets over, tear mesh loose from clips, break wires, and even pull strainer assemblies if the branch is big enough. In windy country around Orange and Bathurst, branch drop after storms is a constant maintenance item.

Root heave: Tree roots grow. As they expand, they can push star pickets sideways or lift them out of the ground. This is particularly common with large eucalypts and established poplars. A picket that was solidly driven three years ago can be loose and leaning from root pressure.

Shade and moisture: Fences in permanent shade dry slower after rain, which accelerates corrosion on non-galvanised components. Moss and lichen growth on mesh can hide damage. Galvanised pickets and fittings cope better in shaded, damp conditions than black bitumen.

Soil conditions: Soil near trees is full of roots, which makes driving pickets harder. You'll hit roots at various depths and the pickets won't always go to full depth.

Regrowth: Young trees and suckers growing through mesh will eventually push the mesh out of shape and break wires. Left unchecked, a sapling growing through a mesh fence will destroy that section within a few years.

PLACEMENT STRATEGIES

Option 1: Run alongside, not through. Where possible, run your fence 3-5 metres away from the tree line rather than through it. This avoids root zones, puts the fence out of direct branch-drop range for most trees, and makes maintenance easier because you can access both sides of the fence without navigating through scrub.

The downside is that stock on the tree side of the fence can shelter under the trees but you lose that 3-5m strip of paddock along the tree line.

Option 2: Run through with wider spacing. If the fence must go through a tree line, increase your picket spacing slightly (6-7m) and accept that you'll need to repair more often. The wider spacing means fewer pickets to be affected by roots and fewer to replace when branches fall.

Use a top wire (not barbed in tree zones — barbed wire catches on fallen branches and makes cleanup harder) and potentially a bottom wire to add structural support between pickets.

Option 3: Use timber posts in heavy tree sections. Where root systems are dense and the ground is full of woody debris, treated timber posts in pre-drilled holes sometimes work better than star pickets. They're less affected by root heave and they're stronger if a branch lands on the fence.

MAINTENANCE FOR TREE-LINE FENCES

Regular patrol: Walk tree-line fences at least quarterly and after every major wind event. Branch damage left unrepaired gets worse quickly — one broken wire leads to mesh sagging, which leads to stock pushing through.

Prune overhanging deadwood: If you can safely prune dead branches that are hanging directly over the fence, do it before they fall. This isn't always practical with tall eucalypts, but for lower branches it's worthwhile prevention.

Control regrowth: Remove any saplings or suckers growing within 1m of the fence line while they're small. A sapling that's 20mm thick is easy to cut. Wait until it's 100mm and it's already damaged the mesh.

Use galvanised in shaded runs: For fence sections that will be in permanent shade, consider galvanised star pickets ($10-$13 depending on height) instead of black bitumen. The galvanising handles constant moisture better and lasts longer in damp conditions.

Check for root heave annually: Walk the tree-line sections and push each picket — if it rocks, roots have loosened it. Redrive or relocate loose pickets before they lean enough to slacken the mesh.

SPECIFIC TREE TYPES TO WATCH

Eucalypts: Branch drop is the primary issue. Red gums and yellow box around Orange are notorious for dropping limbs without warning, especially in hot weather.

Poplars and willows: Aggressive root systems that will push pickets out within a few years. Keep fences well clear of poplar roots.

Pines (Radiata): If you're fencing near pine plantations, the acidic needle drop can accelerate corrosion on non-galvanised components.

Need advice on fencing a tricky tree-line section? We've seen it all across the Central West. Drop into 76 Astill Drive, Orange, or call 0434 093 077.