The Best Kind of Tree to Cut to Make a Post
Determining the best type of tree make the best fence posts is largely determined by your local area. There is a variety of oak called “post oak”, so named because posts split from it last fairly well in the ground. Old timers sharpened the ends of the posts and drove them with sledge hammers. Pratt Logging, in Blackfoot, Idaho now point and cap posts for this exact purpose.
Black Locust is actually fairly prevalent in Idaho, and it makes good posts if you cut trees that have much heartwood or split the white wood off. When you put a post in the ground the white wood quickly rots off, but the black heartwood may last 50 years in the ground.
Juniper is also a good wood. Again, the white wood rots off; it is the heartwood that lasts. If you have cedar, check the heartwood.
The best trees to cut for posts are…
Fir
Locust Locust posts last over 60 years
Locust lasting over 60 years
Eastern White Cedar posts last 80 years and longer
Eastern Red Cedar
Red Oak
White Oak
The Dept of Agriculture or your local extension office should have a brochure on posts made from trees, including the ranking for longevity in the ground. Call your local agent.
However, cutting down a tree to make fence posts will probably not save you any money. Consider the difficulty of hauling a cut tree from its fell location to chopping it into the right size with non-professional equipment. And then, consider the weight and effort will take to place a tree in a truck to haul it to the desired destination. Honestly none of this is worth the trouble just to save a few dollars on a post.
Pratt Logging specializes in cutting and preparing fence posts. The advantage is that they have the equipment to peel the posts, drill the posts (if you need dowel fencing), point and cap the posts, and even cross-cut the posts if you are preparing a Jack Fence or Buck Fence.
And, of course, a treated post will extend the life of the post many years.