Mountains. It is rare or missing in eastern New England and southern
Florida, and most abundant in the Mississippi valley, and there the
largest trees are found. Some exceed 100 feet in height, and four in
diameter. Extreme sizes of 140 feet in height with diameters of from
seven to nine have been reported. The cottonwood was a frontier tree on
the western plains when settlers began to push into the region. It grew
as far west as any hardwood of the eastern forests, and was found beyond
meridian 100, which was supposed to be the boundary between the region
of rains and the semi-arid country. The cottonwood clung to the river
banks and to islands in the rivers, and by that means escaped the
Indian’s prairie and forest fires which he kindled every year to improve
the range for the buffalo. It is supposed that most of the open country
east of meridian 100 was originally timbered, and that the Indians
destroyed the forests by their long-continued habit of burning the woods
and prairies every year to improve the pasture. Cottonwood was the
longest survivor, because it grew in damp places where fires did not
burn fiercely. Black willow was its most frequent companion on the
western outposts of the forests.
The cottonwood was fitted for holding its ground, and pushing forward.
Its light seeds are carried by millions on the wind and by water. The
tree bears large quantities of cotton (hence the name), and when the
wind whips it from the tree, seeds are caught among the fibers and
carried along, to be scattered miles away.
This tree was not much thought of by eastern people who had plenty of
other kinds of wood, but pioneers on the plains who had a hard time to
get any, found cottonwood useful. It made fences, corncribs, stables,
cabins, ox yokes, and fuel. The first canoes made by white men on the
upper Missouri river were of cottonwood. Lumber cut from this tree is
inclined to warp and check unless carefully handled, and this prejudiced
it in the eyes of many; but difficulties of that kind were easily
mastered, and instead of being a neglected wood it became popular. Some
of the largest early orders came from Germany. Vehicle makers in this
country employed it for wagon beds, as a substitute for yellow poplar
when that wood’s cost advanced. Manufacturers of agricultural implements
were pioneers in its use, it being excellent material for hoppers,
chutes, and boxes.
Cottonwood weighs 24.24 pounds per cubic foot, which is approximately
the weight of white pine. It has about the stiffness of white oak, but
only about eighty per cent of white oak’s strength, and fifty per cent
of its fuel value. The wood is very porous, but the pores are small,
usually invisible to the naked eye. The medullary rays are small and
obscure. The appearance of the wood is not improved by quarter-sawing.
The summerwood forms a thin, dark line, so faint that the annual rings
are often scarcely distinguishable. The tree is generally a rapid
grower; heartwood is brown, sapwood lighter, but as a whole, this tree
produces white wood.
The annual cut is declining. It was little more than half in 1910 what
it was in 1899. Some regions where large trees were once abundant now
have few. The sawmill output in 1910 for the United States--including
several species--was 220,000,000 feet. The veneer cut was 33,000,000
feet, log measure; the slack cooperage staves, chiefly for flour
barrels, numbered 44,000,000; and pulpwood amounted to about 18,000,000
feet. The lumber cut was largest in the following states in the order
named: Arkansas, Louisiana, Mississippi, Missouri, Tennessee, Iowa,
Wisconsin, Michigan, Oklahoma, and Minnesota. The tree was lumbered in
forty-one states.
Cottonwood is a standard material in several lines of manufacturing. It
is made into nearly every kind of box that goes on the market, from the
cigar box to those in which pianos are shipped. Manufacturers of food
products are particularly anxious to procure this wood, and it is one of
the best for woodenware, such as dough boards, ironing boards, and cloth
boards. It is used by manufacturers of agricultural implements, interior
finish, bank and office fixtures, musical instruments, furniture,
vehicle tops, trunks, excelsior, saddle trees, caskets and coffins, and
numerous others.
There is no danger that cottonwood will disappear from this country, but
it will become scarce. It is being cut much faster than it is growing,
and is losing favor as a planted shade and park tree, because of its
habit of shedding cotton in the spring and its leaves in the early
autumn.
SWAMP COTTONWOOD (_Populus heterophylla_) is known also as river
cottonwood, black cottonwood, downy poplar, and swamp poplar. Its range
describes a crude horseshoe, running from Rhode Island down the Atlantic
coast in a narrow strip, where it is neither abundant nor of large size;
touching northern Florida; running westward to eastern Texas and thence
up the Mississippi basin and the Ohio river to southwestern Ohio. There
is nothing handsome about its appearance with its heavy limbs and
sparse, rounded crown. In the eastern range the average height is
probably not more than fifty feet but in the fertile Mississippi valley
it reaches 100 and has a long merchantable bole three feet in diameter.
Its bark is rugged, dirty-brown and broken into loose, conspicuous
ridges. It is easily distinguished from the other cottonwoods by the
orange-colored pith in the twigs. The buds are rounded and red and have
a resinous odor. Sawmills and factories never list this wood separately.
It comes and goes as cottonwood. Its uses are the same as those of
common cottonwood. The two species grow in mixture throughout the entire
range of the swamp cottonwood.
TEXAS COTTONWOOD (_Populus wislizeni_) is a rather large tree and is the
common cottonwood in the upper valley of the Rio Grande in New Mexico
and western Texas. The yellowish color of the twigs is apt to attract
attention. The wood is used about ranches and occasionally a log finds
its way to local sawmills; but its importance is limited to the region
where it grows.
MEXICAN COTTONWOOD (_Populus mexicana_) extends its range north of the
Mexican boundary into southern Arizona and southwestern New Mexico. It
is abundant in Mexico where the largest trees are eighty feet high and
three or four in diameter. It is smaller near the northern limits of its
range, and there it hugs the banks of mountain streams. Stockmen use the
trunks, which are usually small enough to be called poles, to make
fences and sheds.
NARROWLEAF COTTONWOOD (_Populus angustifolia_)is a mountain species
which manages to live in the semi-arid regions from the Rocky Mountains
of Canada to Arizona, but is seldom found below an elevation of 5,000
feet, and it ranges up to 10,000. Trunks are eighteen inches or less in
diameter, and fifty or sixty feet high. The seeds are larger than those
of most other cottonwoods. It being a semi-desert species, its wood is
appreciated where it is accessible, and it has local uses only.
LANCELEAF COTTONWOOD (_Populus acuminata_) is a small tree with limited
range, growing in the arid region along the eastern base of the Rocky
Mountains, southward from the Black Hills. It is found also north of the
Canadian border. It is usually fifteen or eighteen inches in diameter,
and thirty or forty feet high. Trunks seldom go to sawmills, but some
local use is made of the wood. Trees are occasionally planted for shade
in towns of western Nebraska and Wyoming.
FREMONT COTTONWOOD (_Populus fremontii_), called white cottonwood in New
Mexico, but elsewhere simply cottonwood, grows from western Texas to
California, and as far north as Utah and Colorado. It sometimes attains
a diameter of five or six feet and a height of 100. The Indians in New
Mexico formerly made rude, clumsy ox carts of this wood, without a scrap
of iron or other metal in the vehicles. One of the carts is preserved in
the National Museum, Washington, D. C. The wood is tough and light, but
it is dull white, with no attractive figure. Even the annual rings are
hardly distinguishable. Logs are occasionally sawed into lumber, and
farmers in western Texas make wagon beds of it.
[Illustration]
BALM OF GILEAD
[Illustration: BALM OF GILEAD]
BALM OF GILEAD
(_Populus Balsamifera_)
This tree is known in different regions by the following names: Balsam,
balm of Gilead, cottonwood, poplar, balsam poplar, and tacamahac. The
usual name, balm of Gilead, is applied in recognition of the supposed
healing virtue of the wax which covers the buds and young leaves. It has
long been used in medicine, but its exact value is still a matter of
discussion. The wild Indians of the North discovered a use for the
balsam in mending their bark dishes, and plugging knot holes in the
wooden trenchers. The wax is slow to dissolve in water, and it resisted
for a long time such soups as were known to the redman’s culinary art.
Bees know the value of the wax and use it to seal cracks and crevices in
their hives and to hold the comb in place. It is popularly believed that
the economy of the wax on the buds is to keep them from freezing. That
view is erroneous, for it would take more than a coating of wax to keep
the buds warm with the thermometer from fifty to seventy degrees below
zero, as it is every winter in some parts of this tree’s range.
Balm of Gilead is a native of the North from the Atlantic to the
Pacific, but its finest growth is about the headwaters of the Mackenzie
river, on Peace and Laird rivers, and the lower valley of the Athabaska.
Sixty years ago Sir John Franklin reported that most of the driftwood of
the Arctic ocean was this species. Since that time the range has been
more definitely determined, and it is now known that the tree grows so
far north that it is for some weeks in darkness, and again in summer for
some weeks in unbroken sunshine. It grows in Alaska nearly 200 miles
north of the Arctic circle. Its natural range southward reaches New
England, New York, Michigan, Nebraska, Nevada, and Oregon.
Trees of all sizes abound, from mere shrubs in the outskirts of its
range to trunks 100 feet high and six feet in diameter in favored
localities. In the United States the best timber seldom exceeds thirty
inches in diameter and sixty or seventy feet in height. The bark on
limbs and young trunks is brownish-gray, frequently so tinged with green
that it is noticeable at a considerable distance; but usually large
trees have reddish-gray bark with deep furrows and wide ridges. Year-old
twigs are clear, shiny reddish-brown; end buds are about an inch long,
the side buds somewhat shorter.
The wood is not distinguishable in appearance from that of the other
poplars or cottonwoods, but it is lighter than most of them, weighing
22.65 pounds per cubic foot, has a breaking strength which places it
among the weakest woods, but in stiffness making a much better showing.
The pores are small, numerous, and are distributed equally through all
parts of the wood.
Balm of Gilead bears seeds abundantly and scatters them widely. It must
do its planting quickly in the short summers of the cold North. It
sticks close to alluvial flats, banks of rivers, borders of lakes and
swamps, and gravelly soils. It grows to a diameter of fifteen inches in
about forty-five years.
Though balm of Gilead is not one of the most important timber trees of
this country, its place is by no means obscure. No separate tally is
kept of it among woods cut for pulp, but it goes with aspen and other
similar species as “poplar.” A little better account is kept of the
amount passing through wood-using factories. The annual quantity so
reported in Illinois is 2,775,000 feet, and it is made into boxes and
crates. The lumber is shipped from the North, since it does not grow as
far south as Illinois. The situation is different in Michigan, for balm
of Gilead grows there. The amount going yearly into factories in that
state is reported at 4,912,000 feet. It is made into many commodities,
but boxes and crates take most of it. The wood is reduced to veneer and
converted into berry buckets, grape baskets, fruit and egg crates, and
other small shipping containers. It is made into excelsior and woodwool
which are used as packing material. Druggist’s barrels are manufactured
from this wood. These are small, two-piece vessels, bored hollow, with a
closely fitting lid, and varying in size from a couple of inches high,
to nearly a foot. They contain powders, perfumes, pills, and other
commodities in small bulk. The wood is worked into pails, tubs, and
kegs. Furniture makers put balm of Gilead to use in several ways. It is
cut thin for shelving; it is made into panels, and is employed as cores
over which to lay veneers of more expensive materials. Woodenware
factories generally keep it in stock in the northern states.
The supply is ample at present to meet all demands. Cutters of pulpwood
probably take more than sawmills, and are satisfied with smaller timber.
Trees are often planted for ornament, but few if any have yet been
propagated for forestry purposes.
HAIRY BALM OF GILEAD (_Populus balsamifera candicans_) is not a species
but a variety, and it is so different from balm of Gilead that it is
entitled to a place of its own. Ordinarily it passes under the common
names applied to balm of Gilead. It is a cultivated tree in eastern
Canada and northeastern United States, where it has escaped from
cultivation and is running wild. Both Sargent and Sudworth say that
nothing is definitely known of the tree’s native range; while it has
been claimed by others that it once grew wild in Michigan but was
destroyed by lumbermen. Probably most planted balm of Gileads are of
this variety, as they are very ornamental. It is a large tree with
branches less upright and crowns more open than in the wild species. The
leaves are wide, heart-shaped, and are usually silvery white beneath
with minute hairs on the margins, on the veins, and leaf stems. It is
not improbable that this variety could be more profitably planted for
forestry purposes than the species which grows wild; but there is no
present indication that foresters favorably consider either of them.
LARGETOOTH ASPEN (_Populus grandidentata_) is named on account of the
shape of the leaves. It is sometimes called aspen, popple, white poplar,
and large poplar. The wood weighs 28.87 pounds per cubic foot, and is
the heaviest of the poplar group except Fremont cottonwood of the arid
southwestern regions. The wood is white, attractive, but not strong. It
was formerly manufactured into chip hats and shoe heels in New England,
and is now used for baskets, crates, boxes, buckets, refrigerators,
excelsior, and pulp. Northern factories usually give it the general name
“poplar,” and for that reason its importance in the lumber trade is
underestimated. Trees may reach a height of seventy feet with a diameter
of two; but a height of forty or fifty is more usual. The species’ range
extends from Nova Scotia to Minnesota, southward to Delaware and
Illinois, and along the Appalachian mountains to North Carolina and
Tennessee.
GUMBO LIMBO (_Bursera simaruba_) is a south Florida species and is known
also as West Indian birch. It is in a family by itself with no near
relative. It is not a birch. The wood is spongy and very light, weighing
less than nineteen pounds per cubic foot. It decays with remarkable
rapidity. Branches thrust in the ground take root and grow. An aromatic
resin, exuding from wounds in the bark, is manufactured into varnish.
The leaves are substituted for tea, and gout remedies are made from the
resin. Large trees are fifty feet high and two feet or more in diameter.
Another Florida tree, not in the same family as this, is also called
gumbo limbo (_Simarouba glauca_), paradise tree, and bitter wood.
Ailanthus (_Ailanthus glandulosa_) is in the same family as paradise
tree, but is not native in this country, though extensively planted
here.
ANGELICA TREE (_Aralia spinosa_). This is a small tree, which usually
develops little or no heartwood. The springwood, or the inner and porous
part of the ring, is broad and yellow, the summerwood, or exterior part
of the ring, is narrow and dark. The wood’s figure, due to the marked
contrast between the outer and inner portions of the rings, is strong.
When finished it shows a rich yellow, but somewhat lighter than dwarf
sumach which it resembles. It is made into small shop articles, like
button boxes, photograph frames, pen racks, stools, and arms for
rocking chairs. Its range extends from Pennsylvania to Texas. It is
sometimes known as Hercules’ club.
ASPEN (_Populus tremuloides_) is widely known but not everywhere by
the same name. It is called quaking asp, mountain asp, aspen leaf,
white poplar, popple, poplar, and trembling poplar. The peculiarity
of the tree which is apt to attract attention, and which gives it
most of the names it carries, is the leaf’s habit of being nearly
always in motion. The day is remarkably still if aspen foliage is
not stirring. This is due to the long, flat leaf stem, which is so
limber that it offers little resistance to air currents. The
difference in color between the upper and lower sides of the leaves
affords sufficient contrast to attract notice, and for that reason a
person will observe the motion of aspen leaves when he might fail to
see a similar movement among the leaves of other species where the
contrast of colors is not so marked. Aspen is credited with being
the most widely distributed tree of North America. It grows from
Tennessee to the Arctic ocean, from Mexico to northern Alaska, from
Labrador to Bering strait. It is found at sea level, and at 10,000
feet elevation among the mountains of California. Its very small
seeds grow in enormous numbers. Winds carry them miles, and scatter
them by millions. They spring up quickly when they fall on mineral
soil. This places it in the class with “fire trees”--those which
take possession of burned tracts. Paper birch is in this class.
Aspen has replaced pines over large burned areas of the Rocky
Mountains. It grows quickly but is weak if it has to contend with
other trees. If crowded it speedily gives up the fight and dies. The
wood is not strong, but is useful for several purposes. Next to
spruce and hemlock, it is the most important pulpwood in this
country, and it is coming into considerable use as lumber. The
whiteness of the wood--it looks much like holly--makes it a favorite
for small boxes and vessels for shipping and containing foods. It is
made into jelly buckets, lard pails, fish kits, spice kegs, sugar
buckets and a long line of similar articles. It turns well, and is
made into wooden dishes. Michigan alone uses two and a half million
feet of it a year; and it is in demand along the whole northern tier
of states from Maine to Washington, but because it is not separately
listed in lumber output, it is difficult to say how much is used.
Trees are usually small, though trunks three feet in diameter are
not unknown. It grows rapidly, and may be expected to fill an
important place in this country’s future timber supply. There will
be no occasion to plant it by artificial means, for nature will
attend to the planting.
[Illustration]
BLACK COTTONWOOD
[Illustration: BLACK COTTONWOOD]
BLACK COTTONWOOD
(_Populus Trichocarpa_)
This member of the cottonwood group is a strong tree that holds its
ground in various latitudes and at many elevations, ranging from sea
level up to eight or nine thousand feet, and in latitude from Alaska to
southern California, a distance of nearly three thousand miles. Its east
and west extension is more restricted and seldom exceeds four hundred
miles. Its habitat covers an area of half a million square miles, and in
that space it finds conditions which vary so greatly that the tree which
can meet them must possess remarkable powers of adaptation.
Beginning in Alaska and the interior of Yukon territory, it has an
arctic climate. It there not only grows on the coast, but it strikes the
interior. It appears on the headwaters of several streams which flow
into the Mackenzie or Hudson bay. It passes south through British
Columbia and enters the United States west of the Rocky Mountains. It
has been reported as far east as Idaho and Montana, but further
information is needed before its limits in that direction can be
definitely fixed.
When it enters California it prefers the elevated valleys and canyons of
the Sierra Nevadas, though it occurs sparingly among the coast ranges.
It is generally found in the Sierras at elevations of from 3,000 to
6,000 feet, though it occurs between 8,000 and 9,000. Among the San
Jacinto mountains of southern California it grows at an altitude of
6,000 feet.
When it occurs at low levels it is usually found on river bottoms and
sand bars, in sandy and humous soils, and there the largest trees are
found. At higher elevations it is more apt to occur in canyon bottoms
and gulches, in moist, sandy or gravelly soil, and in such situations
the black cottonwood is smaller. The best growth occurs where the
climate is humid and the precipitation is great. Beyond the reach of sea
fogs, where the tree depends on soil moisture chiefly, it is smaller.
It is an intolerant tree. It must have light. When it is crowded a tall,
slender trunk is developed and the small crown is lifted clear above its
competitors into the full light. If it cannot succeed in gaining that
position its growth is stunted or the tree meets an early death.
The black cottonwood is the greatest of the cottonwoods. This country
produces no other to match it, and, as far as known, the whole world has
none. The Pacific coast is remarkable for the giant trees it produces,
but most of them are softwoods--the redwoods, the bigtree, the sugar
pine, Douglas fir, western larch, noble fir, Sitka spruce and western
red cedar. This cottonwood is the largest of the Pacific coast
hardwoods. In trunk diameter it is excelled by the weeping oak in the
interior valleys of California, but when both height and diameter are
considered, the black cottonwood is in the West what yellow poplar is in
the East, the largest of the hardwoods.
Sargent says this tree reaches a height of two hundred feet and a
diameter of eight, but Sudworth is more conservative and places the
trunk limit at six feet. The average size is much below the figures
given, but abundance of logs exceeding three feet in diameter reach the
sawmills of Washington and Oregon.
Old trees range from 150 to 200 years in age, but trees under 100 years
old are large enough for saw timber. Records of the ages of the largest
trunks have not been reported.
Black cottonwood is a prolific seeder, but the seeds do not long retain
their vitality. If they find lodgment in damp situations, where other
conditions are favorable, the rate of germination is high. Seedlings are
often very numerous on wet bars.
The excellent quality of the wood and its suitability for many purposes
bring it much demand on the Pacific coast. In the state of Washington
more than 30,000,000 feet were used by wood-using industries in 1910.
Smaller quantities were reported in Oregon and California.
In strength the wood is approximately the same as common cottonwood, but
in stiffness it much exceeds the eastern species. Its elasticity rates
high, and compares favorably with some of the valuable eastern
hardwoods. In weight it is slightly under common cottonwood. Trees are
of fine form, nearly always straight, and are generally free from limbs
to a considerable height.
The wood is grayish-white, soft, tough, odorless, tasteless,
long-fibered, nails well, is easily glued, and cuts into excellent
rotary veneer with comparatively small expenditure of power. It does not
split easily after it has undergone seasoning, and this property
commends it to box makers. It is little disposed to shrink and swell in
atmospheric changes. The absence of odor and taste gives it much of its
value for box making, because foods are not contaminated by contact with
it.
It is manufactured into veneer berry baskets and is one of the most
suitable woods on the Pacific coast for that purpose. Candy barrel
makers use it in preference to most others, and a long line of
woodenware articles draw much of their material from this source. Many
thousands of cords are cut yearly for the pulp mills, where material for
paper is produced. Black cottonwood and white fir are the principal
woods used for pulp on the Pacific coast.
Not only is it used for rotary-cut veneer, but it is made into cores or
backing on which veneers of costly woods are glued in the manufacture of
furniture, interior finish and fixtures for banks, stores and offices.
It serves in the same way in casket making, and is demanded in millions
of feet.
It is employed in amounts larger than any other wood by excelsior mills
in the northern Pacific coast region. It is the only wood demanded by
that industry in Washington and 6,400,000 feet were cut into that
product in 1910.