20 



(5) The edges of the grove which border upon open land should not 

 be thinned enough to leave the stand unprotected from strong winds 

 and sunlight. If other species are crowding the dominant maples, 

 they should be removed; but, as a rule, the borders should remain 

 dense and the trees should be covered to the ground with foliage. 



(6) In cool situations, or in elevated regions, the thinning may be 

 heavier than farther south or in lower lands, where more care is neces- 

 sary to preserve a proper ground cover. Firewood and other timber 

 secured by thinning should pay for the cost of the operation. The 

 necessity for well-located roadways to take out the sap should not be 

 forgotten. 



Figure 2 shows in diagrammatic form a grove of this type before ana 

 after thinning. 



THE MANAGEMENT OF A SAPLING THICKET. 



Throughout the maple region dense thickets of young saplings are 

 common in abandoned fields and pastures. Where a sugar grove is 

 desired, it will pay to take such young growth in hand if no old trees 

 are available in sufficient numbers. Left to themselves, the young 

 trees usually become so densely crowded that even when 20 feet high 

 they number from 2,000 to 3,000 to the acre. Under such conditions 

 growth almost ceases even in the dominant trees, and at a time which, 

 in normal stands, is the period of most vigorous growth. 



The first thinning should be made when the saplings are about 6 or 

 8 feet high, if the owner feels justified in helping them at this time. 

 The largest and healthiest trees, on an average about 12 feet apart, 

 should be selected, and the tops of the others cut back with a hatchet 

 or a corn knife in such a way that they can not overtake the favored 

 individuals. 



Figure 3 gives a conventionalized view of the treatment recom- 

 mended. Cutting back trees in this manner can be done very rapidly. 

 Three men should cut over an acre a day. Although there is no 

 return in firewood or other material from such early thinnings, the 

 young trees will be given a favorable start in their development at the 

 most critical period of growth. The ground cover at the same time 

 will be kept intact by the sprouts, until the selected trees fill out and 

 close up the space with their crowns. When they are about 25 years 

 old the dominant trees, which are about 12 feet apart, will begin to 

 crowd each other, and another thinning must be made to give the best 

 ones room. Experiments are under way to show how much time will 

 be gained by this method in obtaining a stand fit for tapping. All 

 general forest practice shows that the gain over the unthinned thicket 

 should be at least 25 per cent. 



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