THE PRODUCTION OF MAPLE SIRUP AND SUGAR. 7 



the stand keeps its extreme density for a long period, and each tree 

 >TO\VS long and spindling. The i'o rest -grown tree develops slowly 

 on this account, and has a long clean stem and a small crown, while 

 the roadside maple has a short trunk and a great egg-shaped crown 

 of dense foliage. The root system tends to be shallow, with many 

 laterals and an undeveloped taproot. In the forest this character is 

 more marked than in field or roadside specimens, and any sudden 

 opening up of the stand may result in loss by windfall or by a drying 

 out of the roots. 



There is no doubt that the quantity of sap that a tree yields stands 

 in direct relation to the size of its crown, but many sugar makers 

 believe that trees in a forest produce more sap than those in a grove. 

 The explanation is found in the fact that the forest floor with its cov- 

 ering of litter and humus contributes to the vitality of the trees more 

 than the grass carpet of a grove. To obtain a heavy sap production 

 a complete crown cover and a rich deposit of humus are of vital im- 

 portance. 



Within its wide range the sugar maple appears as a predominant 

 tree only in the New England States, New York, southern Canada, 

 northern and western Pennsylvania, and in parts of Ohio, Indiana, 

 Illinois, Michigan, \Visconsin, and Minnesota. In the southern Ap- 

 palachians it occurs in scattered bodies where climatic conditions are 

 similar to those of the North, confining itself chiefly to north slopes 

 or to the coves, on moist, well-drained, rich soils where the heat of 

 the sun is tempered. As a rule it associates with the beech, birches, 

 and basswood, but also mixes with the yellow poplar, hickories, 

 and other hardwoods, and with hemlock and some of the eastern 

 spruces. At the heads of the coves and in the bottoms it often forms 

 pure stands fit for commercial tapping, and its reproduction is every- 

 where excellent. 



In its northern home it is a principal forest tree and often forms 

 from 25 to 75 per cent of the total stand. It prefers a moist but 

 well-drained soil, and seems to do its best on glacial drift or on rocky 

 hillsides and benches. In the cool atmosphere of this region all 

 aspects are equally acceptable, but it avoids or grows sparsely on 

 ridge crests, generallj r leaving the ground in such situations to spruce 

 or to beech. In the extreme northern part of New York State and 

 the adjacent district of Quebec the forest growth is often almost pure 

 maple, and even considerably farther south, where beech and birch 

 become associate trees, the sugar maple holds its own as the dominant 

 species. In northern Pennsylvania, at an altitude of over 1,000 feet, 

 the mixture is much the same as it is in New York. In Ohio, Indiana, 

 and Illinois a similar condition is found; but as the hilly country 

 disappears the maple retreats to the richer and damper soils, leaving 

 great areas to the oaks, chestnuts, etc. This is particularly true of 

 the southern parts of these States. By the time the western and 

 southwestern limits of its range have been reached it has only a scat- 

 tered occurrence, even in the most favorable positions. In southern 

 Michigan the forests are similar to those in New York, but as one 

 approaches the pine region of the North the maple confines itself to 

 the more fertile places. The same is true in Wisconsin and Minne- 

 sota, where the sugar maple reaches its northwestern limit in the 

 I'nited States. 



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