Silviculture

In Britain, planting density has traditionally been around 2500 trees ha^-1, and the species can be established using both bareroot and containerised plants. Forking can be a problem, particularly when planted on open ground that is prone to late frosts. Lawson cypress is palatable to deer, so protection against browsing is important.

After the establishment phase, growth is moderate but consistent over time and on sheltered sites in western Britain yield classes of 18-20 m³ ha^-1 yr^-1 or more have been recorded after 50-60 years. Lawson cypress requires careful selective thinning to favour the best quality stems and to reduce the incidence of forking. However, a long interval between thinning’s is advisable because of slow crown regrowth and limited natural pruning.

Lawson cypress flowers from an early age with regular coning by 20-25 years and natural regeneration can be prolific. This potential for regeneration can be useful when desired but considered invasive when not. The species is very shade tolerant, and so can grow in the understorey of stands of faster growing conifers like Sitka spruce or Douglas fir. In its natural range it grows in mixture with a range of conifers and broadleaves. This combination of shade tolerance and ability to grow in mixture makes it well suited for use in irregular silvicultural systems. Growing in mixture may also reduce the risk from Phytophthora lateralis (see below).

Other species that could be alternatives to Lawson cypress include western red cedar and Japanese red cedar, both of which tend to be more productive on comparable sites. One attraction of Lawson cypress is the valuable timber obtained from larger older trees which is naturally durable.