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tionable only because of the difficulty of working the soil and of 

 keeping the roots protected against frost. All things considered, 

 spring planting, before activity in the tree has begun, is the best, 

 although it is not impossible to plant at other times. 



Progress of Development. Like the wheat or corn plant, the 

 tree seed require as conditions for sprouting sufficient moisture, 

 warmth, and air. Tree seeds, however, differ from grain in that 

 most of the kinds lose their power of germination easily; with few 

 exceptions (locust, pine, spruce), they can not be kept for any 

 length of time. The first leaves formed often differ essentially in 

 shape from those of the mature tree, which may cause their being 

 confounded with other plants, weeds, etc. 



The little seedlings of many, especially the conifers, are quite- 

 delicate, and remain very small the first season; they need, there- 

 fore, the protecting shade of mother trees, or artificial shading, and 

 also protection against weeds. The amount of light or shade given 

 requires careful regulation for some of them; too much light and 

 heat will kill them, and so will too much shade. This accounts for 

 the failure of many seedlings that spring up in the virgin forest. 

 The planter, then, is required to know the nature and the needs 

 of the various kinds of seeds and seedlings, so as to provide favor- 

 able conditions, when he will avoid sowing in the open field such as 

 require the care which it is impracticable to give outside of the 

 nursery. 



Growth in Length and Ramification. While the stalk of wheat 

 or corn grows for one season, exhausts itself in seed production, and 

 then dies, the tree continues to grow from season to season, in 

 length as well as in thickness. The growth in length of shaft and 

 branches proceeds from buds, made up of cell tissues, which can 

 subdivide and lengthen into shoots, as well as make leaves. These 

 buds are formed during summer, and when winter begins contain 

 embryo leaves, more or less developed, under the protecting cover of 

 scales. When spring stimulates the young plant to new activity, the 

 buds swell, shed their scales, distend their cells, increasing their 

 number by subdivision, and thus the leaves expand, and the bud 

 lengthens into a shoot and twig. During the season new buds are 

 formed, and the whole process repeats itself from year to year, 

 giving rise to the ramification and height growth of the tree. The 

 end buds being mostly stronger and better developed, the main axis 

 of tree or branch increases more rapidly than the rest. All these 

 buds originate from the youngest, central part of the shoot, the pith, 

 and hence when the tree grows in thickness, enveloping the base 

 of the limbs, their connection with the pith can always be traced. 

 This is the usual manner of bud formation; in addition, so-called 

 "adventitious" buds may be formed from the young living wood in 

 later life, which are not connected with the pith. Such buds are 

 those which develop into sprouts from the stump when the tree is 

 cut; also those which give rise to what are known as "water sprouts." 

 Many buds, although formed, are, however, not developed at once, 

 and perhaps not at all, especially as the tree grows older; these 



