Trees and How to Know Them [ 341 



In the spring you can see the buds open when the scales are 

 cast off and the new twigs lengthen and form new side branches. 

 On most trees the new twigs are only a few inches long, but on 

 some the growth is more noticeable. 



How to Grow Tree Buds Indoors: Children can observe this un- 

 folding at close range by putting a few twigs of different kinds of 

 trees into vases partly filled with water. Collect the twigs in the 

 fall after the leaves have been shed, and cut them carefully with a 

 sharp knife. Through the winter, change the water each week and 

 rinse the twigs in cool water to keep the bud scales fresh and 

 clean a task performed out-of-doors by winter rains and snow. 



If you keep the twigs in a warm, fairly dark place, the buds 

 will enlarge ahead of those on the trees outdoors. When the buds 

 seem almost ready to burst, they should be moved to a sunny 

 window. 



Trees Have Their Own Birthday Candles: Trunks are not the 

 only parts of trees that have growth marks. Branches and twigs 

 have them too, and you don't have to cut down a tree to see them. 

 Every year a bud leaves a little circle of scars as it casts off its 

 scales. Consequently the distance between every two circles of 

 scars on the branch shows the growth achieved in a year's time. 

 An imaginative child will enjoy likening the bud scars to birth- 

 day candles by counting them he finds the age of any twig. 



Bursting at the Seams: The child who makes a habit of observing 

 some of the details of tree structure will soon notice that while 

 young trees have smooth bark, that of older trees is furrowed and 

 frequently sheds untidily. This also is caused by growth; as the 

 girth of the trunk increases, the constant pressure causes the bark 

 to split. A special layer of cells in the bark forms new corky layers 

 that patch the damaged parts but do not smooth the "wrinkles" 

 that have formed. Trees, like people, often look their age. 



How Trees Are Nourished 



Though we cannot see a tree obtain its food the way we can 

 watch an animal feed, we can observe to some extent how the leaf 



