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There is nothing more natural than a beautifully built rail fence. Since most rail fences are made of cedar, locust, redwood, Osage orange, red mulberry, or tamarack, they will gracefully skirt your property blending in to their surroundings. As with any fence you are building the most important thing to remember is that like any wood that comes into contact with the soil, the posts are prone to decay. Because of this you should always start with fence posts that are made of decay resistant wood. If you cannot find a good quality decay resistant wood or it is too expensive, you can use pressure treated lumber or apply your own non-toxic preservative to the post yourself.

With the exception of redwood and cedar, which are both rot resistant, all raw wood that is exposed to moisture or soil should be treated with a good preservative. It is wise to avoid highly toxic creosote and penta or pentachlorophenol preservatives. You can select a safer preparation such as copper or zinc naphthenate, copper-8- quinolinolate, tributyltin oxide, or polyphase. Since most preservatives are hazardous as liquids, be sure you wear a respirator mask, goggles, gloves, and long sleeves when applying them. Since the wood will need a liberal coat of preservative, small pieces can be brushed on with a natural bristle brush or pad applicator. If at all possible, larger pieces of wood should be dipped in the preservative. Lumber can be soaked in a box or trench lined with plastic, and a bulb operated hand pump can be used to suck the leftover liquid back into the can. If you are applying your preservatives yourself, remember that any low toxity preservatives will need to be reapplied every 3 to 5 years. Copper naphthenate is the only preservative that can withstand contact with the soil.

Fences, such as a rail fence, work well when using pressure treated lumber that is treated at the mill with a long lasting inorganic arsenical preservative, such as chromated copper arsenate. All the post or parts that will be touching the soil should be stamped LP-22. The cross rails and other such pieces should be stamped LP-2. Be sure when choosing your wood that you buy only dry pieces with no surface residue. It is also wise when cutting pressure treated lumber to wear a mask while you are making any necessary cuts to avoid inhaling or swallowing the sawdust. Remember that cutting will expose untreated areas, but arsenical preservatives can be purchased for the sole purpose of treating cut ends.

To begin building your rail fence you will need to drive a stake at each end of the fence line. Stretch a string from one stake to the other to use as a guide in aligning the post. Next you should level the string to see how high each post needs to be, then position the post by dropping a plumb line from the string. When you dig your post holes you will need to dig them deep enough to insure that at least 1\3 of the post is underground and to allow for a large stone beneath each post. Using a post hole digger, dig your holes twice the diameter of the post with its sides angled out at the bottom. Then you should set each post on the stone, packing 6 to 8 inches of gravel around it. Align the post with the guide string and then plumb and brace it with cross beams that run from the top of the post to the top of two stakes. If you have a problem with heavy frost in your area but little or no flooding, fill the hole with a heavy subsoil up to 6 inches from the top. Use a 2 X 4 to tamp the soil around the post down and force several large stones around the post to hold it into place. Fill the rest of the hole with heavy topsoil, heaping it up around the post. If you live in a warm area where the water is high you should use concrete in place of the soil and rocks.

The simplest way to make the rails for your rail fence is to nail the rails to the post. Be sure you use your guide string to ensure that each one is level and use galvanized nails to secure them. If you prefer not to use nails you can use split rails, which will slide into holes that you have drilled through the post. When you choose to use rails with tenons that fit into mortices, these must be assembled as the posts are being set.

If you already have a rail fence but just need to secure a wobbly post you can firm it by driving wooden wedges around the base. In most cases a wobbly or skewed post is a sign that the post has rotted beneath the surface. If you wish to avoid replacing a rotted post you can sink a new but shorter post next to it and bolt both posts together. When the two posts do not touch, insert a spacer block between them and wrap both posts with a perforated metal strapping before you saw the old post off at the soil line. If you need to replace a mortised rail, simply splice a new rail onto the mortised or notched end then glue or screw the joint in place.

Although rail fences are built mostly for decorative purposes and property separation, it is good to note that they will also work well to keep in some forms of livestock. If you plan to use your rail fence to contain animals you might want to place your rails closer together. You should be able to decide this by the size animal you will be trying to contain. Horses will require a higher rail fence that is tall enough to discourage them jumping the fence. Goats and sheep will need a rail fence that has the rails close together and is high enough to discourage jumping.