Farm fencing, specified by the animal

Specify to the animal, then to the terrain

Cattle push and lean. Horses run into fences and need something that will not cut or trap a leg. Sheep and goats go through and under rather than over, and goats will test everything. Predator exclusion is a different problem again.

Watch for: A quote written before anyone asked what you are running. If a contractor is pricing linear feet without asking about the species, the stock density and whether you rotate, they are selling wire rather than designing a fence.

Establish the boundary — and here it is harder

Rural parcels are frequently large, irregular, and last surveyed decades ago. Old fence lines drift, and on acreage a drift of a few feet compounds into a meaningful area over a long run.

Watch for: Rebuilding on the existing line without checking it. On agricultural land, long-standing fence lines carry legal weight in some states and can affect a boundary claim in ways a residential fence never would. If the line matters — and on acreage it usually does — get it surveyed before you rebuild in permanent materials.

Design the corners and the braces first

Every wire fence is held up by its end, corner and brace assemblies. Line posts only keep the wire at height; the tension is carried entirely by the assemblies at each end of a run.

Watch for: Skimped braces. This is the defining failure of amateur and cheap farm fencing — a beautifully strained fence pulling its corner posts out of the ground over the first two seasons. Ask how each corner is built and how many braces a long run gets, because it is where the money should go and the first place a low quote has taken it out.

Clear the line

The run has to be cleared, and on a long fence that is often a bigger job than the fencing. Brush, fallen timber, regrowth along an old line, and access for a post driver all have to be dealt with.

Watch for: Line clearing excluded from the quote and discovered later. It is the most common change order in agricultural fencing. Get it explicitly in or explicitly out, in writing.

Drive the posts and strain the wire

Line posts are usually driven rather than dug and concreted, which is faster and often holds better in undisturbed ground. Wire is then strained to tension and stapled or clipped so it can still move.

Watch for: Wire stapled tight to wood posts. High-tensile wire needs to slide as it expands and contracts with temperature and as an animal hits it; pinning it at every post concentrates the load and breaks it. Also watch for over-straining, which is as damaging as under-straining.

Gates, crossings and water

Gate placement decides how the property works day to day — where you move stock, where a truck and trailer can turn, how you reach water. Creek crossings, gullies and low spots need specific detailing so a flood does not take the fence out.

Watch for: A fence run straight through a watercourse or a wash. Water will take it. These crossings want a designed detail — a floodgate or a breakaway section — rather than a straight run and hope.

Electrification, if you are using it

Electric fence is a psychological barrier rather than a physical one and it depends entirely on the earth system and on the animal learning it. Energiser sizing, grounding and insulation are the whole of whether it works.

Watch for: Undersized grounding. It is the most common reason an electric fence tests fine at the energiser and does nothing at the far corner. Ask how the ground system is built and how you will test the line yourself.