The theory and application of a variable quadrat technique which may be used to assess the adequacy of stocking in stands of young growth are described.

The most significant development in Canadian forestry during the past ten years is that we are now making a conscious effort to grow forests. Economic, social, and legislative forces are gradually changing a policy of forest liquidation to one of sustained yield forest management. With sustained yield forest management rapidly changing from theory to practice, we must deal with factsfacts about the actual state of our forestsnot with unfounded assumptions and wishful thinking.In particular we must consider those factors which principally influence the technical implementation of long-term forest management policiesespecially the productivity, age structure, species composition, and quality of the forest, as well as some general consideration of cutting methods.

Small-scale tests are being undertaken at the Petawawa Forest Experiment Station to determine the feasibility of using Keltex FF, an industrial grade of an Algin derivative, as a mulch to improve the micro-environment of seed spots on exposed sites where high surface temperatures and drought often limit germination and establishment.Algin products which are derived from seaweed have many industrial uses in the form of colloidal suspensions and gels. Keltex F F has received considerable attention as an aid in fire control (I), ( 2) and ( 3), and is available in quantity at a cost of about $120.00 per 100 pounds. Keltex-thickened water combines readily with very small quantities of calcium chloride to produce an instantaneous gel that clings easily to all surfaces, builds up a thick layer of water which absorbs more heat energy, and leaves a plastic-like film when the water finally evaporates. A mulch of this nature may be useful in conserving soil moisture and reducing surface temperatures during the critical period of germination and early establishment of tree seedlings.Tests in 1961 indicated that Keltex-thickened water alone, without the calcium chloride additive, was not a satisfactory mulch; for the solution was absorbed into the surface soil and formed an almost impervious, cemented surface. The addition of a 0.5 per cent calcium chloride solution to Keltexthickened water produced a satisfactory clear gel which had a consistency of thick pancake batter that could be applied readily to seed spots (Figures 1 and 2). Field tests with red pine (Piizus resinosa Ait.

Forests occupy two-thirds of the total land area of Canada's 10 provinces, but less than half of this huge area of 1.4 million square miles of forested land produces timber that can be economically utilized at the present time. Within the accessible and productive forest area of 690 thousand square miles, there are extremely wide variations in the capability of the land to grow timber. For eutample, on a regional basis, the best growth rate in the coastal forests of British Columbia may be up to ten times that of the poorest areas being operated commercially in the northern and northeastern parts of Canada. Even within a given climatic region, production on different sites may vary by a factor of five. When considering the possible land-use of forest areas in Canada on a national basis, it is convenient to visualize three broad zones that differ greatly in forest characteristics and land-use problems. They are: (i) The northern zone lying between the commercial forests and the barren lands to the north. It is characterized by relatively small pockets of productive forest land, mostly along rivers, and extensive areas of scrub forest or other non-productive land. (ii) The central forest zone extending in an irregular east-west belt of continuous and largely productive forest. The land-use in this area lying mostly to the north of the agricultural fringe is predominantly for forestry. (iii) The southern zone between the agricultural land and commercial forest. Here, the land-use is a variable pattern of agriculture and forestry. This discussion deals briefly with the northern zone, in more detail with the central zone which is of prime importance to forestry, and will pay particular attention to the southern zone where the problems of alternative land-uses are most acute. The northern zone is largely undeveloped for any purpose at present, and the primary problem is to find some use for it. Its future potential for forestry and other forms of land management is low because of its inaccessibility and the limited areas of productive land. Unless the demand for forest products increases enormously a sustained forest industry in this northern zone is unlikely. While it is technically possible to bring some of the forested land to a more productive state, it would be better, from an

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