s. The obovate and
almost stalked buds of the Alders are also very conspicuous and
peculiar. In the Balsam Poplar the buds are large, sharp-pointed, and
gummy; in the Ailanthus they cannot be seen.
[Illustration: Fig. 15.]
All the things that might be learned from a small winter twig cannot be
shown in an engraving, but the figures here given illustrate some of the
facts easily determined from such specimens. The first twig (Ash) had
opposite leaves and is 3 years old (the end of each year's growth is
marked by dotted lines on all the figures); the year before last it had
6 leaves on the middle portion; last year it had 8 leaves on the end
portion and 12 on the side shoots of the middle portion. The buds near
the end of the annual growth are strongest and are most apt to grow.
The specimen illustrated was probably taken from the end of a branch of
a rather young and luxuriantly growing tree. Thus the Ash must have
quite a regular growth and form a regularly outlined tree.
The second twig (Sweet Gum) shows 7 years' growth and is probably a side
shoot from more or less within the tree-top. It is stunted in its growth
by the want of light and room. The leaves were alternate.
The third twig (Sycamore) also had alternate leaves; the pointed buds
must have been under the leafstalks, as the leaf-scars show as rings
around the buds. The larger branch grew three years ago. From the
specimen one judges that the Sycamore is quite an irregularly formed
tree. The twig had 11 leaves last year.
The fourth twig (Silver Maple) shows that the plant had opposite leaves,
and supernumerary buds at the sides of the true axillary ones; the true
axillary buds are smaller than those at the sides. It would, in such
cases, be reasonable to suppose that the supernumerary buds were floral
ones, and that the plant blooms before the leaves expand. The annual
growths are quite extended; two years and a part of the third make up
the entire twig. If it was cut during the winter of 1891-92, it must
have had leaves on the lower part in 1889 and 12 leaves on the middle
portion in 1890, as well as probably 4 on the lower portion on the side
shoots. Last year it had 14 leaves on the end portion, two at least on
each side shoot below, making 24 in all.
_Folding of Leaves in the Bud._
There are some peculiarities in the arrangement of leaves in the bud
which can be investigated only in the early spring. The common plans
among trees are--_Infle
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