MINNESOTA CONSERVATION VOLUNTEER March-April 1960 Inventories, management and future plans for forest resources- The Business of Counting Trees By , JAMES T. MORGAN , chief of the division of forest economics research, Lake States Forest Experiment Station, Paul 1, Minn. The Station is maintained by the Forest Service, U.S. Department of Agriculture, in cooperation with the University of Minnesota . "What kind of work do you do, daddy?" is a question many a city-based forester hears from his 5- year old. The answer I give my youngsters is "I count the trees." This seems like a practical occupation to one who is just learning to count and it gets me off the hook. It is also a valid description in its very simplest terms of the complex business of making timber inventories. A forest is in many ways similar to a manufacturer s factory and warehouse. The factory is the land and the trees. The merchandise consists of pulpwood, sawlogs, Christmas trees, and many other products growing to useful size or stored for future use. Good planning by the management depends on continuing or frequent inventories, not only of the stock on the shelves but of the efficiency and capacity of the producing units. Knowing the rate of production (timber growth) and the trend of sales (timber cut), and estimating capacity in terms of future yields are as important as knowing how many board feet or cords of timber are now on the ground. Before 1930 few timber inventories were made except as a preliminary to purchase. Only very general forest resource statistics were available on a state or national basis. Then, during the 1920's, the Scandinavian countries began making forest surveys at the national level. During this same period interest rose in the United States and, as a result, Congress authorized a nationwide field inventory of timber resources. Later it provided for continuing the survey to keep the figures up to date. The first forest survey of the Lake States was begun in Minnesota in 1933 by the Lake States Forest Experiment Station of the U. S. Forest Service, and was finished in Wisconsin early in 1937. THE FIRST BIG JOB Experience in the Scandinavian countries had demonstrated the success of the 'line-plot" method for large-scale surveys. This was adopted in the Lake States. It involved surveying lines in an east- west direction across states with crews stopping at regular intervals along the lines to measure the timber on one-fifth acre plots. The first survey catches the imagination, not only for its contribution to knowledge of our forests, but for the physical effort spent in gathering the information. The Business of Counting Trees 38
MINNESOTA CONSERVATION VOLUNTEER March-April 1960 A straight line extended in any direction in the northern Lake States will soon cross a lake or bog. Since the survey lines had to be straight many of these watery obstacles had to be crossed by crewmen. Much of the logged and burned-over forest land had reverted to brush which added to the natural obstacles in the more northern counties, roads and villages were few. Consequently, the men camped on the line, sometimes for days. This, of course, necessitated back-packing supplies for eating and sleeping, winter and summer. Nearly 15,000 miles of line were surveyed, and 120,000 "plots" were measured in the three states of Minnesota, Wisconsin, and Michigan. E. L. Lawson., present Director of the Division of Forestry, Minnesota Department of Conservation, who was then the field chief for the Lake States survey, summed it up when he remarked at the end of the line in 1937 forest survey-"It's been a big job and a long walk." Information from this survey was compiled for each of the Lake States and along with data from other states, was incorporated into a nationa1 report on the forest resource. After decades of heavy cutting and widespread fires, Uncle Sam and each of the Lake States could take stock of what was left and start planning to rebuild. Reactions to the forest statistics for Minnesota, compiled in 1936, were both encouraging and discouraging. Two-thirds of the original 30 million acres of forest land was left in trees but much of it had degenerated to brush and unusable tree species, Standing sawtimber originally estimated, at 125 billion board feet had shrunk to 11 billion. There was room for optimism, however. The timber volume was 50 per cent higher than pre-inventory estimates. Foresters pointed out that even simple improvements in protection and forest management could bring large increases in timber production. Twenty years later, at the completion of the second Minnesota survey, these predictions were proved correct. A stake marking the last plot on the first survey was set by Joseph O. Grove in March, 1937. Lawson, center, was field chief of the survey. He is now the Director, Division of Forestry. The Business of Counting Trees 39
MINNESOTA CONSERVATION VOLUNTEER March-April 1960 A SECOND LOOK NEEDED In 1946, results of the first survey were 10 years old and becoming obsolete, made so by changing forest conditions. During this year a new inventory was begun, but with a difference. Survey lines were no longer run straight across hundreds of miles of wild country. Instead, forest areas were mapped on aerial photographs and only selected plots were measured on the ground. More plots were measured in heavily forested areas, fewer in poorly stocked and brush areas. The new techniques cut the number of plots required to one-third of the original total, while adding even more accuracy to permit publishing statistics for individual counties. The second job of counting trees was the work of many hands. In Minnesota the public land managers -Federal and State- provided figures for their areas, and the Office of Iron Range Resources and Rehabilitation took on the big task of covering privately owned forest lands. The Lake States Station acted as coordinator and made special surveys timber quality, logging, and natural depletion. As the work progressed reports were published by the IRR&R and the Station, and the job was largely completed by 1953. The new forest resource figures focused public attention on timber volumes, growth, and allowable cut. This last term, allowable cut, means the amount of timber of different stands that can be harvested in the State each year under good forestry practices without damaging our forests or future timber stands. In 1958 the stake was removed by Joseph Grove who set it in 1937 and R.N. Cunningham, formerly in charge of forest surveys, Lake States Forest Experiment Station, now retired. The Business of Counting Trees 40
MINNESOTA CONSERVATION VOLUNTEER March-April 1960 Comparing the "allowable" or “desirable” cut with the amount that actually was cut, district-by- district and species by species, indicates places where cutting may safely be increased. These estimates help public and private agencies to plan their programs for timber sales. They also help industries to plan for timber purchases, plant expansions, and new products. Comparing the 1953 results with those of 1936 showed some encouraging trends. Poorly stocked stands of seedlings and saplings, which covered over 4 million acres in 1936, decreased to about l ½ million acres in 1953. Stands formerly in this class now supported much more tree growth. More growth, along with more roads and better logging methods, had increased the amount of timber that could be cut each year. According to allowable cut estimates, the actual rate of cutting could be stepped up about 50 per cent if it were properly done. The increased cut would have to come primarily from areas where losses from disease and other causes are high, or where much of the timber was mature or decadent. This means the increased cut would be mainly in aspen and other hardwoods, but it should include softwoods in hard-to-reach locations. On the other hand, pine and other softwood stands were being overcut in highly accessible places. The average forest acre still had too few trees to provide one-half the harvest that the land is capable of producing. This was, and is, particularly evident on small private holdings. The failure of many small private owners to practice good forestry is not confined to Minnesota, but is characteristic throughout most of the eastern United States. Each forest inventory establishes a point on the curve of increasing or decreasing forest resources. Trends can be projected into the future, but there comes a time when new data are needed. Because forests are living, changing plant communities and because men and other influences are continually at work in them, forest inventory must be a continuing job. Estimates 10 years old are not good enough for today's decisions so a third inventory of Minnesota's forests is in the making. The general trends shown in the charts can then be extended. The major benefit, however, will come from the detailed examination of all aspects of forest resources in the different areas of the State. How is pine growth holding up in north-central Minnesota? Is balsam fir volume increasing as rapidly as it appears to be? Are softwood areas yielding to less desirable species in the northeastern counties? These are some of the questions the next survey will answer. The Business of Counting Trees 41
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