1. Introduction — The Most Expensive Infrastructure Per Foot on Any Property

Fencing is the single largest infrastructure expense per linear foot on any agricultural property. A mile of four-strand barbed wire fence — the cheapest permanent livestock fence available — costs $8,000 to $14,000 installed in 2026 dollars, depending on terrain and post material. A mile of board fence for horses runs $25,000 to $50,000. A mile of pipe fence can exceed $60,000. Most working ranches carry ten to fifty miles of fence line. The total replacement value of fencing on a mid-size cattle operation routinely exceeds the value of the house, the barn, and every piece of equipment on the property combined.

That cost reality means two things. First, choosing the wrong fence type for your application wastes thousands of dollars per quarter mile. Board fence on a cattle pasture is money burned. Barbed wire around horses is a veterinary bill waiting to happen. Woven wire on a cattle-only operation is double the cost for no added function. Second, fence construction quality determines whether that investment lasts eight years or forty years. The difference between a properly built corner assembly and a poorly built one is not aesthetics — it is whether the entire fence line holds tension or sags into uselessness within five years.

Every fence fails at its weakest point. That point is almost always the corner post, the end post, or the gate post. The wire between posts is the easy part. The engineering that holds everything tight is where fences are won or lost.

What This Section Covers

Seven fence types compared by cost, lifespan, and appropriate application. Post materials and treatment chemistry. Corner assembly construction — the single most important structure in any fence line. Installation procedures for barbed wire, woven wire, board fence, and high-tensile. Gate construction and hanging. Long-term maintenance.

2. Fence Types Compared

Every fence type exists because a specific animal, terrain, or budget demanded it. No fence is universally best. The table below compares the seven most common agricultural fence types on cost, expected service life, and appropriate application.

Fence Type Installed Cost per Linear Foot (2026) Expected Service Life Best Application
Barbed wire (4-strand) $1.50–$2.75 20–30 years (treated wood posts), 15–20 years (T-posts) Cattle, large pasture divisions, perimeter fence on rangeland
Woven wire / field fence $3.00–$5.00 20–30 years Sheep, goats, hogs, mixed small stock, predator exclusion (with additions)
Board fence (3- or 4-rail) $6.00–$12.00 15–25 years (treated pine), 30+ years (hardwood/composite) Horses, high-visibility property lines, front-of-property aesthetics
Post and rail (split rail) $8.00–$15.00 25–40 years (cedar/locust) Decorative boundary, horse paddocks (with added mesh), historic properties
Pipe fence (2-3/8" or 2-7/8") $12.00–$20.00 40–60 years Cattle working pens, corrals, heavy-use areas, horse arenas
Cattle panel (16' welded) $4.00–$6.50 20–30 years Small paddocks, pens, temporary divisions, garden fence
High-tensile smooth wire $1.25–$2.50 25–40 years Large acreage cattle and horse operations, electric fence systems, deer exclusion (8+ strand)

Selection Principles

Cattle only, large acreage: Four-strand barbed wire remains the most cost-effective permanent cattle fence. High-tensile smooth wire with electrification is the modern alternative — lower material cost, longer life, but requires a reliable energizer and regular testing.

Sheep, goats, or hogs: Woven wire is mandatory. Barbed wire does not contain small stock. Goats will go through, over, or under any fence not specifically designed to stop them. Hogs will root under anything not buried or pinned.

Horses: Board fence or high-tensile smooth wire. Never barbed wire for horses. A panicked horse hitting barbed wire at speed will sustain lacerations that can be career-ending or fatal. Board fence is the traditional standard. High-tensile with electrification trains horses to respect the fence before they hit it, which is the entire point.

Working pens and corrals: Pipe fence. Nothing else survives the sustained impact of cattle being worked through chutes, alleys, and sorting pens. Board fence will be broken. Cattle panels will be bent. Pipe holds.

Budget-limited small acreage: Cattle panels (also called stock panels or combo panels) are the fastest, most forgiving fence to install. They come in 16-foot welded sections, require minimal tools, and tolerate imperfect post spacing. They are not economical for large acreage but are hard to beat for pens, garden fencing, and small paddocks.

3. Post Selection

The post determines the lifespan of the fence. Wire and boards can be replaced relatively cheaply. Replacing posts means rebuilding the fence from scratch. Every dollar spent on post quality is a dollar that pays back over decades.

Treated Wood Posts

Pressure-treated wood is the most common fence post material in the United States. The treatment chemical determines both longevity and safety.

CCA (Chromated Copper Arsenate): The gold standard for longevity. CCA-treated posts last 40+ years in ground contact. CCA was restricted from residential use by the EPA in 2003 due to arsenic content, but remains legal and available for agricultural and industrial use. CCA posts are identifiable by their green tint. Do not burn CCA wood — the ash contains concentrated arsenic. Acceptable for all livestock fencing where the wood will not be chewed (cattle, sheep). Not recommended where horses will crib on posts.

ACQ (Alkaline Copper Quaternary): The most common residential and general-purpose treatment since the CCA restriction. ACQ-treated posts last 20–30 years in ground contact. ACQ is significantly more corrosive to metal fasteners than CCA — use only hot-dipped galvanized or stainless steel hardware. Standard electrogalvanized staples and nails will corrode and fail within 5–10 years in ACQ-treated wood. This is the single most common new-fence failure mode in the last twenty years: ACQ posts with the wrong fasteners.

Copper Naphthenate: An oil-based treatment that is the only preservative approved for organic farming applications by some certification bodies. Posts treated with copper naphthenate last 20–25 years in ground contact. The treatment gives wood a dark brown-green color and a noticeable petroleum odor when fresh. It is paintable and does not corrode standard fasteners. More expensive per post than ACQ but avoids the fastener compatibility problem entirely.

Naturally Rot-Resistant Wood

Eastern Red Cedar: The traditional fence post of the American Midwest and South. Heartwood cedar posts last 15–25 years in ground contact without any chemical treatment. Sapwood rots quickly — use only heartwood posts. Cedar is lightweight, easy to handle, and does not require special fasteners. Availability and cost vary enormously by region. In Texas and Oklahoma, cedar posts are often the cheapest option because cedar is an invasive species being cleared from rangeland. In the Northeast, cedar post prices are three to four times higher.

Osage Orange (Bois d'Arc / Hedge Apple): The hardest, most durable fence post available in North America. Osage orange heartwood posts last 50+ years in ground contact — some documented at 80 years. The wood is extremely dense (specific gravity 0.85), extremely hard, and extremely difficult to drive staples into. Pre-drill for all fasteners. Osage orange was the original living fence of the Great Plains before barbed wire existed; miles of Osage hedge were planted in the 1850s–1870s specifically as livestock barriers. Posts cut from mature Osage are still the most durable natural option available.

Black Locust: Second only to Osage orange in ground-contact durability. Black locust heartwood posts last 25–40 years. The wood is somewhat easier to work than Osage but still very hard. Common in the Appalachian region and parts of the Midwest. Like Osage, it is considered invasive in some areas and may be available cheaply from clearing operations.

Steel Posts

T-Posts (studded steel): The workhorse of wire fence construction. T-posts are driven with a post driver — no digging required. Standard lengths are 5.5 feet and 6.0 feet. T-posts do not rot, but they rust. Longevity depends on the galvanizing quality and soil chemistry. In neutral or alkaline soils, a good T-post lasts 20–30 years. In acidic soils (pH below 5.5), rust can compromise a T-post in 10–15 years. T-posts cannot serve as corner posts, end posts, or gate posts — they have no lateral strength. They are line posts only.

Pipe Posts (used oil field pipe / new schedule 40): The most durable post available. Used 2-3/8" or 2-7/8" drill pipe is widely available in oil-producing regions at $1.00–$3.00 per foot. New schedule 40 pipe costs more but provides a consistent product. Pipe posts last 40–60 years with minimal maintenance. They require welding or bolt-on brackets for rail attachment and are primarily used for corrals, working pens, and heavy-use areas.

Post Lifespan Comparison

Post Material Ground Contact Life (years) Cost per Post (2026) Notes
CCA-treated pine (4–5" dia.) 40+ $8–$14 Agricultural/industrial use only
ACQ-treated pine (4–5" dia.) 20–30 $7–$12 Requires HDG or stainless fasteners
Copper naphthenate pine 20–25 $10–$16 Organic-compatible
Eastern red cedar (heartwood) 15–25 $5–$15 (regional) No treatment needed
Osage orange (heartwood) 50–80 $8–$20 (regional) Pre-drill for all fasteners
Black locust (heartwood) 25–40 $6–$15 (regional) Regional availability
Steel T-post (5.5') 15–30 $4–$8 Line posts only, no corners
Steel pipe (2-3/8" used) 40–60 $6–$18 Requires welding or brackets

4. Corner and End Assemblies — The Most Important Structure in the Fence Line

A fence is only as strong as its corner posts. Every foot of tensioned wire in the fence line is pulling against the corner and end assemblies. If the corner fails, the entire fence goes slack. Most fence failures are corner failures. Most corner failures are construction failures — undersized posts, insufficient depth, missing or improperly installed diagonal braces, or inadequate tamping.

H-Brace Construction

The H-brace is the standard corner and end assembly for all tensioned wire fencing. It consists of two vertical posts connected by a horizontal brace rail, with a diagonal wire providing the inward pull that keeps the assembly rigid under tension.

Post sizing for H-brace corners:

  • Minimum post diameter: 6 inches for corners, 5 inches for end posts (line-end H-braces)
  • Minimum post length: 8 feet (allows 3.5 feet in the ground, 4.5 feet above ground for a standard 4-foot fence)
  • Post depth: 3.5 feet minimum. In sandy or loose soil, 4 feet. The failure mode for corner posts is almost always that they were not set deep enough. Depth is not negotiable.

Brace rail:

  • Length: 8 feet between posts (center to center). This is the standard. Shorter braces reduce the mechanical advantage of the assembly. Longer than 10 feet and the brace itself becomes a weak point.
  • Diameter: 4–5 inches minimum. Use the straightest post available for the brace rail.
  • Connection: The brace rail sits in a notch or pocket cut into the vertical posts, approximately 6 inches below the top of the post. The bottom of the notch must be flat so the brace bears on solid wood, not just friction. Some builders pin the brace with a 3/8" drift pin through the vertical post and brace; others rely on the notch and diagonal wire to hold everything in compression. Pinning is better.

Diagonal brace wire:

  • The diagonal wire runs from the top of the far vertical post (the one away from the fence line) down to the base of the near vertical post (the one the fence line attaches to). This is the direction that matters — top-far to bottom-near. Reversing the diagonal does nothing useful.
  • Use smooth 9-gauge wire or 12.5-gauge high-tensile wire, doubled. Wrap each end around the post at least three times and twist tight.
  • Tension the diagonal by inserting a stick or short pipe between the two strands of the doubled wire and twisting until the wire is taut. This is called a Spanish windlass. Twist until the wire hums when flicked. Do not over-twist — the wire should be taut, not at its breaking point.
  • The diagonal wire is what makes the H-brace work. Without it, the horizontal brace rail is just a spacer. With it, every pound of pull on the fence wire is converted into downward force on the near corner post, which resists by being buried 3.5 feet in the earth. The deeper and tighter the post, the more pull the assembly can resist.

Double H-brace: For corners that carry tension from two directions (any 90-degree corner), build a double H-brace — one H-brace assembly facing each direction of the fence line. The corner post is shared between both assemblies. For line-end posts (dead ends), a single H-brace is sufficient. For pull-through points where the fence changes direction at an angle less than 90 degrees, a single H-brace on the inside of the angle is usually adequate if the angle is gentle (150 degrees or more). Sharper angles need a double brace.

Setting posts in the H-brace:

  1. Dig all post holes before setting any posts. Hole diameter should be twice the post diameter.
  2. Set the corner post first. Plumb it in both directions. Tamp in 6-inch lifts with a tamping bar, using a mix of the original soil and gravel. Do not use concrete for corner posts in clay soils — concrete creates a smooth surface that clay cannot grip, and the post will eventually work loose. In sandy soils, concrete is acceptable and sometimes necessary.
  3. Set the second post at exactly 8 feet center-to-center. Plumb and tamp.
  4. Cut the brace rail notches. Install the brace rail.
  5. Run and tension the diagonal wire.
  6. Allow the assembly to sit for at least 48 hours before tensioning fence wire against it. This lets the tamped earth consolidate around the posts.

5. Barbed Wire Installation — Four-Strand Cattle Fence

Four-strand barbed wire is the default cattle fence in North America. It has been the default since the 1870s, and no cheaper effective alternative has replaced it. The design is simple: four horizontal strands of barbed wire attached to posts, with the spacing designed to discourage cattle from reaching through, stepping over, or crawling under.

Wire Spacing (from ground up)

Strand Height from Ground Purpose
Bottom wire 12 inches Prevents calves from crawling under
Second wire 22 inches Fills the gap
Third wire 32 inches Main body deterrent
Top wire 42–48 inches Prevents reaching over

Total fence height is 42 to 48 inches depending on cattle type. For standard commercial cattle, 42 inches is adequate. For Brahman-cross cattle or any breed with a reputation for fence-testing, 48 inches.

Post Spacing

  • T-posts: 12–16 feet apart. Closer spacing on hilly terrain, wider on flat ground. In rolling terrain, posts should be placed at every grade change so the wire follows the contour of the ground rather than bridging over low spots (which creates gaps cattle can crawl under).
  • Wood posts: 16–20 feet apart, with T-posts between them as needed. Every fourth or fifth post should be a wood post to provide stapling surface and lateral stability.

Tensioning Barbed Wire

Barbed wire is tensioned using a fence stretcher — either a ratchet-type stretcher that grips the wire with jaws, or a chain-type stretcher that wraps around a post and pulls the wire with a come-along. The wire should be pulled tight enough to eliminate visible sag between posts but not so tight that it hums like a guitar string. Over-tensioned barbed wire breaks in cold weather when the metal contracts. The wire should deflect 3–4 inches when pushed firmly at the midpoint between posts.

Procedure:

  1. Unroll the wire along the fence line on the ground. Use a wire spinner or unroller — do not try to unroll barbed wire by kicking the spool. That is how people get wrapped up.
  2. Attach the wire to the first corner or end post by wrapping it around the post and back on itself at least four times, then securing with two wire clips or a crimped sleeve.
  3. Walk the wire to the far end. Attach the fence stretcher.
  4. Pull to tension. Check the sag at several points.
  5. Secure the wire to the far corner post the same way as the near end.
  6. Staple or clip to each intermediate post, working from one end to the other.

Attaching Wire to Posts

Wood posts — stapling: Use 1.5-inch or 1.75-inch galvanized fence staples. Drive the staple at a slight angle to the grain — never straight with the grain, which splits the post. The staple should hold the wire firmly against the post but allow the wire to slide through the staple slightly. Do not pound the staple flush — leave 1/16 inch of play. This allows the wire to equalize tension across multiple spans when an animal hits the fence. If every staple is pounded dead tight, a hit on one span cannot borrow slack from adjacent spans, and the wire breaks at the impact point.

T-posts — clips: Use the wire clips that come with the T-posts, or buy aftermarket clips sized for your T-post brand. The clip wraps around the T-post's studded face and captures the wire. Attach clips with the hook facing upward on the top wire and downward on the bottom wire to prevent the wire from lifting off in wind or animal contact. Middle wires can face either direction.

6. Woven Wire (Field Fence) for Sheep, Goats, and Hogs

Woven wire — also called field fence, stock fence, or by brand names like Red Brand or Bekaert — is a mesh of horizontal and vertical wires welded or knotted at each intersection. It is the only wire fence that reliably contains small livestock. Barbed wire does not stop sheep, goats, or hogs. Smooth wire does not stop them either unless electrified. Woven wire physically blocks them.

Sizing Notation

Woven wire is described by a three- or four-number code: for example, 1047-6-12.5. The first two digits are the number of horizontal wires (10). The next two digits are the fence height in inches (47). The first number after the dash is the spacing of vertical (stay) wires in inches (6). The last number is the wire gauge (12.5). For small stock, the critical numbers are:

  • Goats and sheep: 1047-6-12.5 minimum. The 6-inch stay spacing prevents animals from pushing through between vertical wires. Twelve-inch stay spacing (1047-12-12.5) is cheaper but goats will push through it. Use 6-inch stays or add a strand of barbed wire or electric wire at nose height.
  • Hogs: 1047-6-11 or heavier. Hogs are strong and persistent. Use the heaviest gauge available and add a strand of barbed wire or hot wire 4–6 inches off the ground to discourage rooting under the fence.

Stretching Woven Wire

Woven wire is stretched differently than barbed wire. Because the mesh can deform, you cannot simply pull it from one end — the bottom wires will stretch more than the top, creating a wavy, uneven fence.

Proper technique:

  1. Unroll the wire along the fence line. Stand it up against the posts and prop it with temporary ties.
  2. Attach a stretcher bar (a flat steel bar the height of the fence with evenly spaced holes or notches that capture each horizontal wire) to the free end.
  3. Attach the fence stretcher or come-along to the stretcher bar, not to a single wire.
  4. Pull evenly. The stretcher bar distributes the pull across all horizontal wires simultaneously, keeping the mesh square and the stays vertical.
  5. Tension until the horizontal wires are taut but the vertical stays still have slight flex. Over-tensioning woven wire distorts the knots and weakens the fence.

Bottom Wire

The bottom of woven wire fence is the weak point against burrowing and rooting animals. Three options:

  1. Bury the bottom 4–6 inches by trenching along the fence line before stretching. Effective but labor-intensive.
  2. Pin the bottom wire to the ground every 2–3 feet with ground stakes (J-hooks or rebar pins). Faster than trenching, nearly as effective.
  3. Add a strand of barbed wire or electric wire 4 inches below the bottom of the woven wire. This deters digging without requiring burial.

Post Spacing for Woven Wire

T-posts every 10–14 feet. Woven wire is stiffer than barbed wire and spans well, but the mesh catches wind load, especially in open country. In high-wind areas, reduce spacing to 10 feet. Wood posts every 50–60 feet for stapling surface. All corners and ends get full H-brace assemblies — woven wire carries more tension than barbed wire because of the larger surface area.

7. Board Fence — The Horse Fence Standard

Board fence exists for one reason: horses. Horses are the only common livestock species that combine high value, thin skin, panic-driven flight response, and the size and speed to destroy themselves on wire fence. A twelve-hundred-pound horse hitting barbed wire at 30 mph sustains injuries that can cost thousands in veterinary care or end the animal's working life. Board fence is visible — horses see it and stop before hitting it. It is smooth — no barbs to lacerate skin. And it is solid enough to absorb impact without wrapping around a leg.

Rail Configuration

Three-rail: Adequate for mature, well-trained horses in small paddocks. Bottom rail at 18 inches, middle rail at 36 inches, top rail at 54 inches. The 18-inch gap at the bottom is large enough for a foal to roll under in some configurations — if foals are present, add a bottom board or switch to four-rail.

Four-rail: The standard for breeding farms, large paddocks, and any situation where foals are present. Bottom rail at 12 inches, second rail at 24 inches, third rail at 36 inches, top rail at 48–54 inches. Four-rail eliminates the gaps that three-rail leaves.

Board on Inside vs. Outside

This is one of the most frequently debated points in horse fence construction.

Boards on the inside (livestock side): The boards face the animals. When a horse pushes against the fence, the force pushes the boards against the posts. The posts carry the load in compression. This is structurally stronger. It also presents a smooth post face to the outside, which looks cleaner from the road. The downside: a horse rubbing on the fence can push boards off the nails or screws from the inside.

Boards on the outside (road side): The boards face outward. When a horse pushes against the fence, the force pulls the boards away from the posts. The nails or screws carry the load in tension (pullout force). This is structurally weaker. However, it prevents horses from pushing boards off the posts. Most horse farms put boards on the inside for structural reasons and accept the occasional board replacement from rubbing.

Best practice: Boards on the inside, fastened with ring-shank nails or structural screws (not smooth-shank nails, which pull out easily). If rubbing is a problem, add a hot wire on insulators 6 inches inside the top rail. One shock trains most horses to stop leaning on the fence permanently.

Post Spacing

8 feet for 1x6 pine boards. 10 feet maximum. Standard dimension lumber (1x6 or 2x6) does not span much beyond 10 feet without visible sag between posts. If using 2x6 hardwood or composite boards, 10-foot spacing is solid. Some builders stretch to 12-foot spacing with heavy boards, but sag develops over time and looks poor.

Fasteners

Use hot-dipped galvanized ring-shank nails (3 inches for 1x6, 3.5 inches for 2x6) or #10 structural screws. Three fasteners per board at each post — two near the edges, one in the center. Do not use smooth nails. Do not use deck screws (they are brittle and snap under impact load). Ring-shank nails in ACQ-treated wood must be HDG or stainless — standard galvanized ring-shank nails will corrode.

8. High-Tensile Smooth Wire — The Modern Alternative

High-tensile fence uses 12.5-gauge wire with a breaking strength of approximately 1,800 pounds — roughly three times the breaking strength of standard soft fence wire. This strength allows the wire to be tensioned to 200–250 pounds per strand, which keeps it taut across longer spans with fewer posts. The result is a fence that uses less material, lasts longer, requires less maintenance, and can be optionally electrified.

Components

Spring assemblies: Coiled springs installed inline on each wire strand, one per span between corner assemblies. The spring absorbs impact when an animal hits the wire and allows the wire to return to tension rather than stretching permanently. Without springs, high-tensile wire either breaks on impact or stretches and goes slack. Springs are not optional — they are what makes the system work.

In-line strainers: Ratchet devices installed on each wire strand that allow tension adjustment after installation. As the wire stretches slightly over its first year, or as temperature changes cause the wire to expand and contract, the in-line strainer lets you retension without detaching the wire. Install one strainer per wire per span. Place strainers where they are accessible — not at the top of a hill or in the middle of a creek crossing.

Insulators: If the fence will be electrified, each wire must be isolated from the posts with insulators. For T-posts, snap-on insulators are standard. For wood posts, tube insulators or nail-on porcelain insulators work. For a permanently non-electric fence, insulators are unnecessary and the wire can be stapled directly to wood posts (with the same stapling rules as barbed wire — slight play, angled to the grain).

Wire Spacing

High-tensile fence can run from 4 strands (cattle minimum) to 12+ strands (deer exclusion). Common configurations:

  • 5-strand cattle fence: 10", 20", 30", 40", 50" from ground. Alternate hot and ground wires if electrified (strands 1, 3, 5 hot; strands 2, 4 ground).
  • 7-strand sheep/goat fence: 6", 12", 18", 24", 32", 40", 48" from ground. Closer spacing at the bottom deters crawling under.
  • 8–12 strand deer exclusion: Fence height to 8 feet. Effective as a physical barrier even without electrification — deer can jump a 4-foot fence easily but hesitate at 7+ feet. Adding electrification to the top and bottom strands increases effectiveness significantly.

Electrification

The main advantage of high-tensile over barbed wire for cattle is the option to electrify. An energizer (also called a charger or fencer) delivers a high-voltage, low-amperage pulse to the hot wires. The pulse is painful but not dangerous to livestock (or humans). The shock trains animals to respect the fence, which means fewer impacts, less maintenance, and longer fence life.

Energizer sizing: One joule of output energy per mile of single-wire fence. A 5-strand fence running one mile needs a 5-joule energizer. Oversize the energizer — vegetation touching the wire drains energy, and an undersized energizer will not deliver an adequate shock through weed load. A 10-joule energizer on 5 miles of 5-strand fence provides a comfortable margin.

Grounding: The energizer ground rod system is the most neglected component of electric fence. Without adequate grounding, the circuit does not complete and the animal feels no shock. Minimum: three galvanized ground rods, 6 feet long, driven full depth, spaced 10 feet apart, connected with continuous galvanized wire. In dry or sandy soils, use more rods — six or eight. Poor grounding is the number one cause of electric fence failure.

9. Gates — Livestock Gate Hanging and Construction

A gate is a moving part in a structure designed to be rigid. Every gate sags over time. Every gate gets harder to close over time. Every gate eventually drags on the ground if it was not built with sag prevention from the start. Gate construction is gate-sag prevention. Everything else is secondary.

Gate Types

Tubular steel gates: The standard commercial livestock gate. Available in 4-foot to 16-foot widths. Powder-coated or galvanized. Buy commercial gates — they are manufactured with proper diagonal bracing and hinge alignment. Building a steel gate from scratch that works as well as a $150 commercial gate is not economical unless you have a welding shop and idle time.

Wire gates: A section of wire fence that can be unhooked and laid down to create a gap. The cheapest possible gate. Functional for infrequently used crossings in remote pasture. Not suitable for daily use — opening and closing a wire gate daily wears out the operator and the wire.

Wood gates: Custom-built from lumber. Common for horse properties and aesthetic applications. Wood gates require a diagonal brace running from the bottom of the hinge side to the top of the latch side. This diagonal carries the weight of the gate in compression and prevents sag. Without it, the gate will sag within one season. The diagonal must run bottom-hinge to top-latch — the other direction does not resist sag.

Sag Prevention

  1. Diagonal bracing: Every gate wider than 4 feet needs a diagonal brace. Metal gates have this welded in. Wood gates need it built in. The diagonal runs from the bottom of the hinge side to the top of the latch side.
  2. Gate post bracing: The gate post carries more leverage than any other post in the fence line because the gate hangs from it as a cantilever. Gate posts must be a minimum of 6 inches in diameter, set at least 3.5 feet deep, and braced with a full H-brace assembly. A gate hung on an unbraced post will pull that post out of plumb within one year.
  3. Hinge selection: Use heavy-duty strap hinges or bolt-through hinges rated for the gate weight. Standard screw-in lag hinges are adequate for gates up to 8 feet. For 12-foot and 16-foot gates, use bolt-through hinges with backing plates to distribute the load across more of the post's cross-section.
  4. Wheel kits: For gates wider than 12 feet, a wheel on the latch end that rolls on the ground prevents sag entirely by supporting the gate weight at both ends instead of cantilevering from the hinge post alone. Wheel kits are inexpensive and dramatically extend the service life of wide gates.

Cattle Guards

A cattle guard is a set of parallel steel rails or pipes set over a pit at a fence-line crossing, allowing vehicles to pass without opening a gate. Cattle will not walk on the rails because their hooves slip between them. Cattle guards are expensive to install ($2,000–$8,000 depending on width and load rating) but eliminate the daily labor of opening and closing gates on frequently used crossings.

Construction basics:

  • Pit depth: 18–24 inches below the bottom of the rails.
  • Rail spacing: 4–6 inches between rails. Wider spacing risks catching small hooves (calves, foals) and causing leg injuries.
  • Load rating: Size for the heaviest vehicle that will cross. A standard ranch cattle guard must handle loaded grain trucks and equipment trailers — 40,000 to 80,000 pounds.
  • Wings: Fence wings extending 10–15 feet from each side of the cattle guard prevent animals from walking around it. The wings must tie into the main fence line with no gaps.
  • Drainage: The pit must drain. Standing water breeds mosquitoes and accelerates rust. Slope the pit floor to one side and install a drain pipe.

10. Fence Line Maintenance

A fence built right needs minimal maintenance. A fence built wrong needs constant maintenance, which it usually does not get, which is why it falls apart. The maintenance schedule below assumes the fence was built correctly.

Annual Inspection

Walk the entire fence line once per year, minimum. Twice per year is better — once after winter (freeze/thaw heaves posts, ice loads break wire, fallen trees damage spans) and once after the growing season (vegetation load on wire, post damage from livestock rubbing).

What to check:

  • Post condition: Lean, rot at the ground line, broken posts. Push on each post. A solid post does not move. A rotting post gives.
  • Wire tension: Sag between posts. High-tensile fence can be retensioned with in-line strainers. Barbed wire requires re-stretching the affected span.
  • Staple and clip integrity: Loose staples, missing clips, wire that has pulled free.
  • Corner and end assemblies: Diagonal wire tension, brace rail condition, post plumb. Corner assemblies under-tension are the first sign of future fence failure.
  • Ground clearance: Soil erosion under the bottom wire creating gaps large enough for livestock to crawl under. Fill eroded areas or add a strand of wire.

Post Replacement

When a post rots at the ground line — and eventually, every wood post does — you have three options:

  1. Pull and replace: Pull the old post, set a new one in the same hole. This is the correct repair but requires detaching all wire from the old post and reattaching to the new one. For T-posts, this is a 20-minute job. For wood posts in a multiple-wire fence, it can take an hour or more.
  2. Sister a new post: Drive a T-post or set a new wood post immediately adjacent to the broken post and attach the wire to the new post. Leave the old post in place. This is the fast field repair and is perfectly acceptable for line posts. Do not sister corner posts — replace them properly.
  3. Steel post sleeve: Drive a length of steel pipe over the broken post stub and attach wire to the pipe. A compromise repair that is faster than full replacement but less durable.

Wire Repair

Barbed wire break: Splice using a wire splice tool or by hand. Overlap the broken ends by 12 inches, wrap each end around the other wire at least six times, and bend the cut ends inward so they do not snag livestock or clothing. A properly wrapped splice holds 80–90% of the wire's original breaking strength.

Woven wire damage: Small tears (one or two wires broken) can be patched by wiring a piece of matching woven wire over the damaged area, tying at each intersection. Large tears (multiple wires across several stays) require cutting out the damaged section and splicing in a new piece using stretcher bars on both sides.

Vegetation Management

Vegetation touching electric fence wire drains the charge and eventually shorts the fence to ground. On non-electric fence, heavy vegetation loads sag wire and accelerate rust at contact points.

Mechanical control: Mow or brush-hog the fence line once or twice per year. Keep a 3-foot clear zone on both sides of the fence.

Chemical control: Selective herbicide applied to the fence-line strip. Effective but requires care to avoid drift onto pasture forage or nearby crops.

Grazing control: Running goats along the fence line is remarkably effective at keeping vegetation down. Goats prefer browse (woody stems, brush, vines) over grass, which is exactly what grows up into fence wire.

11. Sources

  1. USDA Natural Resources Conservation Service. Conservation Practice Standard: Fence (Code 382). National Handbook of Conservation Practices. Revised 2020.
  2. Grandin, Temple. Livestock Handling and Transport. 5th ed. CABI Publishing, 2019.
  3. Midwest Plan Service. Fences for the Farm and Rural Home. MWPS-11. Iowa State University, 2000.
  4. American Wood Protection Association. Use Category System for Treated Wood. AWPA Standard U1-21. 2021.
  5. Forest Products Laboratory, USDA Forest Service. Wood Handbook: Wood as an Engineering Material. General Technical Report FPL-GTR-282. Madison, WI. 2021.
  6. Engler, Mark, and Joe Paschal. Fencing Materials and Construction. Texas A&M AgriLife Extension Service, Publication E-246. 2018.
  7. Lehmkuhler, Jeff. High-Tensile Electric Fence Construction. University of Kentucky Cooperative Extension Service, Publication ASC-225. 2017.
  8. McCall, Chester. The Fence Bible: How to Plan, Install, and Build Fences and Gates to Meet Every Home Style and Property Need. Storey Publishing, 2005.
  9. Gerrish, Jim. Management-Intensive Grazing: The Grassroots of Grass Farming. Green Park Press, 2004.
  10. Shelton, M. Predator Management for Sheep and Goat Operations. Texas A&M AgriLife Extension, B-6145. 2004.

Tags: [practical-skills] [facility-design] [beginner]