Split Rail and Buck-and-Rail Fences

What is the difference between split rail and post and rail?

Post and rail is the broad family: upright posts set in the ground with horizontal rails attached. Split rail is one version of it, using split rails with rounded ends that slide into holes in the posts, as the University of Georgia's fencing bulletin describes. Others use poles or planks nailed or screwed on. The look differs, but the structure is the same: the fence depends on its posts.

Buck-and-rail is built on a different idea. Instead of being set in the ground, the rails hang on X-shaped wooden bucks that stand on the surface. FWP's guide calls these buck and rail or jackleg fences and groups them as three-dimensional fences. Worm fence is older again, with rails stacked and interlocked in a zigzag and no posts at all.

What are FWP's recommended dimensions for a post and rail fence?

FWP's wildlife-friendly post and rail design uses pressure-treated posts 6 to 8 feet long, spaced 10 to 14 feet apart, with a top rail no more than 40 inches above the ground. Lower wires go at 18 and 28 inches, with the second wire at least 12 inches below the top rail, or you can use lower rails with at least 18 inches of clearance from the ground. It says a half-round top rail attaches more snugly and needs shorter bolts, and that a 2-rail fence is preferable to a 3-rail for wildlife.

It also says that unless the fence is quite low, rounded poles work better for the top rail than square or split rails, which hold more snow in winter and can deter elk and deer. That is a real trade-off for anyone who wants the split rail look on an open property. Boards and planks are not recommended unless the fence is low with ample clearance, because they create a visual barrier.

Should you build a buck-and-rail fence?

FWP's advice is cautious. It says buck and rail or buck and wire designs should be avoided, because they make a formidable barrier and hazard to wildlife, and that the fence requires high maintenance: wooden bucks and rails rot and collapse under snow loads and winds. It concedes that some landowners like the look for its tradition and history, but says buck fence should only be used for very short reaches and specific situations, such as wet or very rocky soils, with frequent crossings for wildlife.

That last point is why it still has a place in western Montana. Where you cannot dig or drive a post, in very rocky ground or wet soil, a fence that sits on the surface may be the sensible option. If you build one, FWP's dimensions are specific: top rail no higher than 40 inches, at least 18 inches between the bottom rail and the ground, at least 18 inches between rails, and leave out the horizontal rub rail in several sections or completely, as the fence does not need it for stability.

Can you add wire to a rail fence?

On a post and rail fence, yes, and it is a common way to hold livestock or pets. Our Florence projects include post and rail with welded wire. FWP's design uses smooth lower wires rather than barbed, and our guide to wildlife-friendly fencing explains why smooth matters. Think about what you are holding in, since the University of Georgia bulletin says welded wire fabric is not recommended for horses because its joints do not hold up, and favors woven mesh; see horse fencing.

On a buck and rail fence, FWP is firm: never add woven wire or barbed wire. It says that combination, or placing the fence on steep terrain, makes it a complete barrier to wildlife, and that three-dimensional buck and barbed wire is a particular entanglement hazard. Long stretches of wire may also be pulled down by wildlife.

What is a worm fence and does it still make sense?

A worm fence, also called a zigzag rail fence, stacks rails alternately and interlocks them at the joints. FWP says it is useful where posts cannot be driven, most often where local timber is available and the terrain is rocky and uneven, and is easily hopped by most hooved animals when kept low. Its specs: three to four stacked rails per section, 8 to 11 feet long, stacked only 2 to 3 feet high, joints at a 30 degree angle, with bottom rail ends set on a rock or short log to slow decay.

For extra stability it suggests fastening rails with long spikes and driving rebar either side of the joint, and dropping rails to the ground every 400 feet and at swales and stream crossings for wildlife. It also lists the downsides: rot, the number of rails needed, how much ground the fence takes up, and maintenance. It is a decorative or boundary choice rather than a livestock fence at that height.

Does a rail fence count as a legal fence in Montana?

It can. MCA 81-4-101 lists fences of four boards, rails or poles, on standing or leaning posts not over 17 feet 6 inches apart, as legal fences, with a brace on the inside of each leaning post. A legal fence must generally be between 42 and 48 inches high. Notice that this does not line up with the 2 or 3 rail, 40 inch wildlife-friendly design. If you are relying on a fence to meet the legal standard against a neighbor's cattle, check the details with an attorney. See Montana fence law; this is general information, not legal advice.

Town rules can apply as well. In the City of Missoula, any new fence needs a permit, a front yard fence is limited to 4 feet, and a rear yard fence to 6 feet. A rail fence in a front yard usually fits comfortably. Our guide to fence height and permit rules covers the rest, and covenants may also address fence style; see HOA landscape and fence approval.

How long does a rail fence last?

It depends on the wood, the ground contact and the upkeep, and we would rather not quote a universal number. The Forest Products Laboratory says posts and other fence parts in ground contact should be pressure-treated or naturally durable, and that above ground the two last comparably, with weathering as much a factor as decay. Its chapter on finishing says water repellents work exceptionally well at slowing water absorption into end grain, the most absorptive surface.

Joints and cut ends are where water sits, so keep those clean and treated. See staining and sealing a wood fence. Treated posts must be rated for ground contact, as the University of Georgia bulletin warns. On frost, a rail fence is light but its posts can still heave; see frost depth and fence post footings.

How do you lay a rail fence on a slope?

Rail fences usually follow the ground, stepping or angling with it, and that can look natural on the rolling lots common in the valley. Our Florence post and rail project, for example, was built to follow the existing grade. Pay attention to post spacing: the University of Georgia bulletin suggests planning runs in even multiples of the rail length, so you do not end with one short odd section.

Slope also affects animals. FWP's guide shows how a fence becomes harder to cross as the ground steepens: a 42 inch fence is roughly equivalent to 62 inches on a 30 percent slope. So on a steep hillside you may want a lower top rail than you would use on the flat, or a gap for wildlife.

Which rail fence is right for your property?

Choose post and rail for most boundary and pasture lines where you can get posts in the ground. Add wire if you need to hold animals, and keep to two rails and a rounded top if wildlife move through. Choose split rail for looks on a low, decorative boundary. Consider buck-and-rail only for a short stretch of rocky or wet ground where posts are impractical, and keep FWP's dimensions in mind. Choose worm fence where it suits the setting and you have the rails and the room.

For a broader view of materials, compare wood, vinyl, metal or composite fencing. If elk and deer are the issue, a rail fence will not keep them out; see deer and elk fencing.

How HJ builds rail fences

We build custom post and rail fences across Missoula and Ravalli counties, with or without wire, and we repair older lines. We will walk the line with you, look at the soil and slope, and talk through what you need the fence to do. See our custom fencing and fence repair pages, and the rest of our Montana Landscaping, Lawn & Irrigation Guide.

Call HJ Property Care & Tree Service at (406) 215-7319 or request a free fence estimate and we will walk the line with you.

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