Cold storage of conifer seedlings: An update from the British Columbia perspective

In both the temperate and boreal regions of North America and Scandinavia, conifer seedlings are routinely cold stored for several months in order to accommodate the schedules of nurseries and tree planters alike. It is critical to the success of the practice to understand the biology of the seedlings, in particular the influence of environmental factors such as temperature and light on their yearly cycle. Since Hocking and Nyland's important 1971 review, research has characterized the effects of different methodoligical parameters of the cold storage process (lift date, storage temperature, moisture, etc.) on a number of physiological aspects of the trees (root growth potential, photosynthesis, stress resistance). This has led to better guidelines and awareness on the manipulation of seedlings for cold storage. This article will review some of that research, concentrating on the Western experience. Key words: conifer seedlings, nurseries, cold storage, physiology, stress resistance