that of other evergreens and also with that of the
broad-leafed trees. Have them describe in what particulars the shapes
differ in different trees. They will come to realize that the difference
in shape results from difference in length, direction, and arrangement
of branches. They may notice that other evergreen trees resemble the
pine in that the stems are all straight and extend as a gradually
tapering shaft from the bottom to the top, that all have a more or less
conical shape, and that the branches grow more or less straight out
from the main stem, not slanting off as in the case of the maples and
elms.

Coming close to the tree, the pupils may first examine the trunk. By
using a string or tape-line, find its diameter and how big it is around.
Tell them how big some evergreens are (the giant trees of the Pacific
Coast are sometimes over forty feet around). Have them notice where the
trunk is largest, and let them find out why a tree needs to be so strong
at the ground. Heavy wind puts a great strain on it just at this point.
Illustrate by taking a long slat or lath, drive it into the ground
firmly, and then, catching it by the top, push it over. It will break
off just at the ground. If a little pine tree could be taken up, the
pupils would be interested in seeing what long, strong, fibrous roots
the pine has.

Let them examine the bark of the trunk and describe its colour and
roughness. The fissures in the bark, which are caused by the enlarging
of the tree by the formation of new wood under the bark, are deeper at
the bottom of the tree than at the top, the tree being younger and the
bark thinner the nearer to the top we go.

Let the pupils look up into the tree from beneath and then go a little
distance away and look at it. They will notice how bare the branches are
on the inside, and the teacher will probably have to explain why this is
so. They will discover that the leaves are nearly all out toward the
ends of the branches as they get light there, while the centre of the
tree top is shaded, and the great question that every tree must try to
solve is how to get most light for its leaves. The pupils will now see
an additional reason why the lower limbs should be longer than the upper
ones. The greater length of the lower limbs brings the leaves out into
the sunlight.

The reason for calling this tree an "evergreen" may now be considered.
Why it retains its leaves all winter is a problem for more advanced
cl