However, you might guess that nature has figured out untold numbers of interesting ways to do this. The drawing here shows twigs from three common street-trees. From left to right we see the Sweetgum, the White Ash, and the Sycamore. The conical items are buds , in which reside the next growing season's new leaves and stems.
Similar buds can hold flowers.
Notice how different the three kinds of bud are. The dots inside the leaf scars are bundle scars , and they are scars resulting when the tiny tubes carrying water, nutrients and other things from the main stem to the leaf broke when the leaf fell off. Notice how these three items differ so drastically from twig to twig. In fact, once you begin looking at them, tree twigs are as different from one another as tree leaves. No one is sure why some twigs have wings such as these, but several species do.