From tree to fence post: A do-it-yourself guide
As maturing exotic woodlots become more common on farms, the do-it-yourself option for turning the trees into fence posts and battens is increasingly popular.
Hew McKellar - farmer, forester, and double covenantor - submitted the following advice.
If you have pine trees over about eight years of age you can make your own posts. With trees over 15 years you can make battens.
Because the wood quickly gets sticky and difficult to work with, it is much better to process a tree from felling to peeled and stacked post in the same day rather than cut down several trees and process them over a longer period.
- Before taking out the chainsaw, plan what type of posts or battens to cut from which part of your trees. See the sketchbelow for a guide. The hardest piece to find is for stays: the ideal is a double trunked tree to have a piece small enough yet mature enough.
- Do not waste your time with round posts at the top of the tree, the wood is too young and the staples will fall out. The posts from a larger tree with three cut sides make good posts for stockyards or for railings. The wide slab posts are good for angle posts or in unstable ground.
- For battens, pruned butts (the length of timber above the tree stump) make the best option, but be ruthless in discarding poor pieces with knots etc. The cost doubles from milling a piece to having it treated.
- After felling a tree, mark it off into post lengths, taking care to avoid knots in the middle of the post lengths even if this means cutting out a block to waste. Don't be too fussy if a post butt is not straight (nobody is going to see it and it helps the post from twisting). If the tree is a comfortable cutting height above the ground you can rip* it at this stage, otherwise cut the post lengths and take them to a place where you can lift them clear of the ground for ripping. (* ripping means cutting along the grain of the wood.)
- When ripping, always cut with the chainsaw blade as perpendicular as possible to the wood (ripping with the saw at a low angle to the trunk will result in long slivers of wood quickly clogging up the saw). You may wish to nail a board along the cut line to get it straight but after a while you will not need this provided you always cut straight downwards and not at an angle.
- Stand the post up against something and peel the bark off with a good sharp axe.
- Stack the posts immediately, as within a few minutes they get sticky to handle.
- Dry the posts, either by air-drying on site or at a treatment plant. Carry out this test on a few posts to see if you can air-dry on site: if air-drying posts develop a white fungus on them they have failed the test, as this is the fruiting part of the fungus and by then it has passed through the wood. If you are in an area where you can air dry, spray them with anti sap stain (get it from a sawmill) but be sure to have an open stack and use dry wood over 50mm thick as fillets to separate the drying posts.
Cost savings are not major when labour is taken into account. However, making your own fence posts utilises timber that would otherwise be thinned to waste.
Open SpaceTM Magazine No.53, December 2001 © QEII National Trust