The Tulip Tree 



81 



shaped like tulips, al- 

 though not so bright. 

 Persons who are not 

 very observing may pass 

 under a tulip tree in blos- 

 som in May or June and 

 fail to notice the flowers 

 among the leaves, but no 

 one fails to admire them 

 when his attention is 

 once called to them. 



The " clean" trunk 

 of the tulip tree. The 

 tulip tree is a favorite 

 with lumbermen, not 

 only because the trunks 

 are long and straight 

 but also because they 



FIG. 48. Leaves and flowers of the tulip 

 tree. 



are " clean " to a great 



height. By a clean trunk is meant one that is free 

 from limbs, so that the lumber made from it will be 

 free from knots ; for knots appear in the wood where 

 limbs grow out from the trunk of a tree. 



Trees standing close together in the woods grow tall 

 because each receives light mainly from above, and they 

 produce clean trunks because the lower branches, being 

 shaded, die and fall while they are still small. Trees 

 growing in open places do not grow so tall as those in 

 the forest, but they have a wider spread. Their lower 

 limbs persist and attain a large size. Such trees do not 

 make lumber of high grade. Few other trees found in 



