Trees, like people, become friends only when we have become well
acquainted with them and have a knowledge of the characteristics that
make them something special to us. This bulletin about the trees of
Texas may be used as a handy reference for identifying trees you do not
know, or it may be used as the basis for developing tree friends. The
following is a guide or lesson plan that will help make a friend of each
tree studied.
I. Object of Study
Each kind of tree has certain identifying characteristics which
mark it as being different from other kinds of species of trees.
By careful observation and examination these identifying points
may be learned and you can feel that you know the tree.
II. Source of Study Material
1. The locality in which you live probably has some trees you know.
Why do you know them? Start by studying these trees and make
them fast friends.
2. You also will find some trees you are not sure about or do not
know; next, study these one by one until you are sure you will
always know them.
3. Wherever you may be or whenever you see a tree you do not know,
observe it carefully, collect enough facts and sample material
to study until you learn to know it.
4. Books, articles, pictures and references will help to learn some
trees you cannot actually see but which are of interest to
you.
III. Approach to Tree Study
1. One tree should be studied at a time as a general rule although
it may be an advantage to select somewhat similar trees and
study them by comparisons.
2. Field study of the growing tree is the most satisfactory. Observe
a number of the same kind of trees as there are individual
variations in some characteristics.
3. If possible collect for reference and further study samples of
leaves, twigs, bark, wood, flowers and fruit. BE CAREFUL in
collecting samples. It is better not to have samples than to
deface or injure the tree. No one will object to your studying
their trees if you do no damage.
IV. Procedure
1. General
(a) First observe the tree as a whole taking into consideration
all the points that attract your attention. Very often there
will be some one thing that either alone or in relation to
other points attracts your attention. That feature when
studied may be the key to your really learning to know the
tree.
(b) The suggestions that follow as to observations of various
parts of the tree do not limit the study of those points for
perhaps you will learn to know the tree from some feature not
listed.
2. Form of tree
Note the size, shape and branching habit; observe its location
in relation to other trees that might affect its form.
3. Bark
Observe thickness, roughness, type of fissures and color of
bark. Studying the bark as a means of winter identification is
particularly worthwhile.
4. Leaves
Study type, size, shape and variations on the same tree; note
arrangement on twigs; describe by the blade, stalk, margin,
venation, base and tip; know their texture and color.
5. Twigs
Note lateral arrangement on branches; observe whether flexible
or stocky and whether rough or smooth; study differences
between new growth and old; learn any distinctive color,
smell, or taste; cut a cross-section and note size, shape,
color and size of pith; note presence or absence of lenticels.
6. Buds
Like bark, the buds are helpful in winter identification. Note
size, scale coverings, and shape. Observe arrangement and
position on twigs; compare terminal and lateral buds.
7. Leaf-scars
Study scars left by falling leaves as to size, form, position
and occurrence; note bundle-scars (appear as marks in scar) as
to number, shape, size, and arrangement.
8. Flowers
Study promptly at proper season; trees vary widely in
flowering habits; observe as to size, form, shape of parts,
color and arrangement; and learn whether the tree has one or
two kinds of flowers—if two, whether male and female flowers
are on same tree.
9. Fruit
Study of fruit also is seasonal. When it is available, observe
type, form, structure and method of distribution.
10. Wood
Identification of trees by wood forms a separate study but
often field identification of trees can be aided by
observation of distinctive points about the wood such as
color, taste and general structure.
11. Habitat
An interesting and often useful help in tree identification is
to note the growing habits of trees, whether in dry or moist
places, what other species same type sites, whether it grows
better in open places or in more sheltered locations and the
like.
V. Summary
If you have followed through on your study of a tree, covering the
eleven points listed, you will really know the tree for all time.
However, even if you cannot or do not make your study as
thoroughly as is suggested, you should at least select enough
distinctive characteristics about the tree to study that you will
be able to identify it both in the summer and the winter seasons.
VI. References
Your school and public library should have one or more books on
trees. You will find books on southern trees most helpful. While
it is impractical to provide a complete list of books on trees,
the partial list below is furnished for your information, with the
understanding that no discrimination is intended:
Fernald, M. L. _Gray’s Manual of Botany._ Eighth edition. American
Book Company, 1950.
Green, C. H. _Trees of the South._ The University of North
Carolina Press, 1939.
Harrar, E. S., Harrar, J. G. _Guide to Southern Trees._ Whittlesey
House, 1946.
Kearney, T. H., Peebles, R. H. _Arizona Flora._ University of
California Press, 1951.
Sargent, C. S. _Manual of the Trees of North America._ Second
Edition. Houghton Mifflin Co., 1922 (_at Project Gutenberg_).
Vines, R. A. _Native East Texas Trees._ Houston Museum of Natural
History, 1953.
Vines, R. A. Trees, _Shrubs and Woody Vines of the Southwest._ The
University of Texas Press, 1960.
[Illustration: Cross Section of the Trunk of an Oak Tree.]
A. Cambium
B. Inner bark
C. Outer bark
D. Sapwood
E. Heartwood
F. Pith
G. Ray
[Illustration: TWIG FEATURES]
Terminal Bud
False Terminal Bud
Twig Scar
Bud Scales
Superposed Bud
Lateral Leaf Buds
Bundle Scar
Flower Bud
Leaf Scars
Lenticel
Stipule Scar
Terminal Bud Scale Scars
Pith
Chambered
Solid