SIXTY-FOUR MILLIONS OF DOLLARS— II. 



PRACTICAL MANAGEMENT OF THE FOREST GROWTH. 



By tile Chief vf tlie Forestry Division of the 



N OUR FORESTS, the young 

 growtli consists usually of a 

 mixture o f seedlings and 

 sprouts from the stump. The 

 latter grow more rapidly than 

 the seedlings, and are shorter- 

 lived. If they come from old 

 stumps, especially high 

 stumps, they rarely grow into desirable trees. So 

 it is preferable to reduce this kind of growth to a 

 minimum and favor the trees that come from seed. 

 Seedlings that have vegetated under the old growth 

 many years have sometimes lost the capacity of 

 vigorous development when set free, and so are to 

 be taken out in the first thinning. 



The shade-enduring kinds, like maples, beech, and on 

 good soils, oak and ash, may recuperate after having 

 been shaded for a time, while the light-needing kinds 

 that have not been killed out by the shading are rarely 

 serviceable for the new growth. 



In thinning out sprouts, the interior shoots should 

 preferably be removed, for they do the least for the 

 shading of the ground and draw most upon the roots of 

 the mother stock ; while the outside shoots form new 

 roots if the cutting has been done properly, i. e. close 

 to the ground. There are next to be cut such as are 

 bushy, and others, like aspen, willows, soft maples, etc. , 

 which in the full sunlight shoot up and grow too thickly 

 in view of their inferior value. 



Any which are to be specially favored must be freed 

 from too close neighbors, even if some of good quality 

 have to fall. Especially is it necessary to know which 

 are the quicker-growing and which the shade-enduring, 

 in order to determine which need assistance and which 

 must be kept back. 



The cuttings of poor kinds are made gradually during 

 the first ten to fifteen years of the growth, and late 

 summer or early fall. August and September are the 

 best months for this trimming, as then the year's growth 

 is completed and the foliage allows one to form judgment 

 as to the conditions of each individual. These cuttings 

 must be done carefully, however, so that the crown- 

 cover be not broken for a longer time than two or three 

 years ; that is to say, the remaining growth must be 

 able to close up and shade the ground fully within that 

 time. There is danger of cutting too much by the 

 amateur forester who wants to have something to do 

 with his wood-lot, when simply waiting would be better. 



When the crop has been brought into desirable com- 



United States Dehartnient of Agi icultui e. 



position, there comes another series of thinnings to 

 hasten the formation of valuable wood. Do this by 

 cutting certain trees in order to give the remaining room 

 to develop more quickly and favorably. Life, as well 

 as rapid growth, depends upon the amount of foliage to 

 assimilate food. 



It is the number of trees that yield the best result, 

 not the greatest number, that we try to keep growing. 

 What this best number is, depends naturally on the kind 

 and age of the trees. In the average, in the 20th year 

 10 square feet, in the 40th year 40, in the 60th year 100, in 

 the 80th year 125, and in the looth year 160 square feet 

 growing space. Or 4,300, 1,100, 435, 350 and 270 trees 

 per acre respectively at the ages noted, would represent 

 about the proper average. There are from 50 per cent, 

 to 75 per cent, more shade-enduring trees possible on 

 an acre than light-needing, and more trees on poorer 

 soils, sometimes two to four times as many, than on good 

 soils, and more in the valley than on the higher eleva- 

 tions ; so that while a pine growth at, say 60 years, may 

 show 400 trees to the acre, a beech growth, under the 

 same conditions, may contain from 600 to 700 trees. 



Left to itself, as the forest grows up, and as the indi- 

 vidual trees develop, each trying to hold its ground and 

 struggling for light, there is a natural thinning taking 

 place, some trees lagging behind in growth and being 

 shaded out, until, in old age, only as many trees remain 

 as can occupy the ground without incommoding each 

 other. We are to give direction and assist in this 

 struggle, to hasten its results and obviate useless expend- 

 iture of energy. 



As a rule, it is best to begin thinning when the struggle 

 for light begins to show unmistakably, that is, when a 

 decided difference in individual development can be 

 seen, and the dominant growth be discerned from the 

 laggards. Generally they are begun in light-foliaged, 

 rapid growing trees with the 15th to 25th year; with 

 shade-enduring species one may wait until the 25th to 

 30th year ; that is the time when the greatest annual 

 height growth is attained and diameter development is 

 desirable. 



In small wood-lots, where the owner uses perhaps the 

 thinned-out material himself, a continuous gradual 

 thinning is perhaps best ; while on large areas it may be 

 more practicable to cut over a larger area at once and 

 repeat it in a few years. 



The oftener the thinnings are repeated, the better for 

 the remaining growth. The recurrence may be every 

 two or three years in pines and rapid growing soft 

 woods, while with slow growers every five years may be 

 sufficient. Conditions of growth and the judgment 



