On the stem there are other scars, which are different from the ordinary leaf scars, and which are like bands of fine lines round the stem. What are these? Now if the single big leaf stalk leaves its scar so clearly on the stem, what kind of scar would a number of thin scales lying close together be likely to leave? Will it not be a number of narrow scars in a band, just such a scar as we have here (fig. 66, ~a~, ~a~^1, and ~a~^2). If you mark a bud on a tree or one of the branches in your room and watch it unfold, and keep a note of it till the autumn, you will find at its base where the bud scales were, that there is then a scar just like this. Whenever you see such a scar you will know that it has been left by a bud. Now you know that, as a rule, trees have buds only once a year, so that each of the bud scars along the stem must represent a past year’s bud, and if you count these scars along the length of the stem it will tell you the number of years the stem has been growing. For example, in fig. 66 the twig shows us five years’ growth if you count the last bud which will grow out to form a shoot. [Illustration: Fig. 66. Branch of Sycamore, showing leaf stalk (~l~) with bud (~b~) in its axil. Scars of leaf stalks (~s~) and large terminal bud (~t~) with scars (~a~), (~a~^1), and (~a~^2) left by the terminal buds of past years.] The buds which come in the axils of the leaves along the stem may form new leaves, or may develop into side shoots with new stems and leaves. There is another bud, generally bigger than these, which grows at the end of the shoot (~t~, fig. 66). This has just the same structure as the others, but it will certainly grow out to form a stem and carry on the line of growth of the main shoot, unless it is injured. The amount that the shoot grows in one year depends on very many things, on the light and warmth it gets, on its food and the growth of its neighbours. Hence, in the growth of different shoots in the same year, or the same shoot in different years, we find very great differences. Sometimes a number of bud scars lie very close together, showing that for several years it had only grown a small amount, while in the years following it may have added very much to its length. In some plants there are little side shoots which never grow much, and always remain quite short; for example, in the larch each tuft of leaves grows on a little stunted stem which represents several years’ growth, and which never reaches any length (~see~ fig. 67). [Illustration: Fig. 67. Larch, with tufts of leaves growing from short side shoots.] Not only do we get leaves and stems packed away in buds, but the flowers for next year are there also. For example, examine several of the big horse chestnut buds from the outer branches of the tree, and you will be sure to find tiny sprays of young flowers packed away in the hearts of some of them.