What Are the Pros and Cons of Using Larch Fencing?

Larch wood is one of the most durable materials for outdoor use. The wood consists of durable fibers and weather-resistant sticky resins, eliminating the need for expensive and toxic preservatives necessary for other types of wooden fencing. Larch fencing, however, can be expensive during times of peak demand. In some regions where larch does not grow extensively or where competing softwoods dominate the forests, larch fencing may be therefore unavailable or prohibitively expensive to transport. As a softwood, larch fencing is difficult to cut and may twist or warp with changes in humidity.

The larch tree is an unusual type of deciduous conifer tree. As a gymnosperm, the larch reproduces by seeds within cones, but drops its needles in the autumn season along with other deciduous trees. While larch trees are among the fastest growing conifers, there are only 10 to 15 different species of larch in the world. The larch is also afflicted by various pests, diseases and forest animals, reducing its availability and its lifespan. For this reason, lumber companies in the United States and Canada tend to harvest and mill the more common Douglas fir, western hemlock and western white pine at more affordable prices.

In Europe, larch trees grow more abundantly, particularly the hybrid Dunkeld Larch in northern Scotland and Switzerland. Larch was once a very common wood for boat planking and decking, outdoor larch furniture and framing and cladding for homes. Similar to other coniferous softwood trees, such as pines and spruces, larch contains resin canals that ooze arabinogalactan, a water soluble resin. The resin acts as a waterproof sealant, covering wounds and openings in the pores of the wood. Larch fencing is therefore highly resistant to rot and warping.

Eurasia is home to most species of larch, with the strong and durable Dunkeld Larch as the most common timber product for larch fencing and other exterior lumber needs. The honey-colored wood needs no treatment with preservatives. With sun-exposure, larch fencing fades to a light honey-colored hue that some gardeners find attractive. Larch can be difficult to mill, however, as the sticky resins that work so well waterproofing also tend to bind saws and fasteners. This type of fencing may also drastically shrink, causing the larch fencing to twist or warp with fluctuations in humidity and temperature.