from place to place is well understood. The squirrel is notably diligent in this regard and buries his food stores in the earth, where they may grow if he fall a victim to predatory appetite before he himself eats his buried store of food. Some seeds like those of the burdock have organs of attachment by means of which they may secure transportation by passing animals, but it is not now recalled that any tree seeds are so strongly specialized in this way.

Forest trees have insect enemies as well as insect friends, and sometimes there are great invasions of insect pests attacking certain species, such as the pine in the Black Hills region of South Dakota a few years ago, and the larches of Canada about 1896. Last and most potent of the animal agencies is that of man himself; and it is his relation to the forest that forms the main theme of the present work.

COMMERCIAL TREE SPECIES OF AMERICA.

George B. Sudworth, accepted in this work as authority on the forest tree species of the United States," gives 510 distinct species, not counting hybrids nor species variations, some of the latter of which would rank almost as distinct species.

The following table will show

Of these sixty families eighteen are represented in the United States only in the southern portion of Florida or along the Mexican boundary, being tropical plants and not characteristic of the flora of the country as a whole. These families include thirty-one genera and forty-two species, and there are sixty-four species in other families which might also be classified as tropical, making a total of 106 tropical species. There are seventeen species which were not originally indigenous to this country but are now found growing here wild, having escaped from cultivation. Of the remaining species (as has already been stated in discussing the influence of the Rocky Mountains as a botanical barrier), 212 are found only in the eastern and middle United States, 159 are found only on the Pacific slope or in the Rocky Mountains, and sixteen

5 See footnote No. 2, page 19.

Charles S. Sargent, in his monumental work, "The Silva of North America," states (preface to Vol. XIII.) that 585 species are treated. Such differences arise chiefly in two ways-first, from some botanists considering as distinct species trees which others consider as mere varieties; second, from differences of judgment as to whether certain species are trees or shrubs. In addition is the frequent discovery and identification of new species.

species are common to both geographical divisions. Canada is not known to have any tree species not in Sudworth's list, and her flora comprises only 127 of the 510 species listed by him.

THE COMMERCIALLY VALUABLE WOODS.

When we come to consider the woods which are of commercial importance the list becomes restricted to such an extent that room may be made for it here. Many other woods than those given have local uses or are valuable for other purposes than for lumber, but this list includes practically all the woods which furnish sawlogs, and a few besides, on account of their wide distribution. Sudworth's list is followed throughout in giving the range, except where otherwise stated: Pinus strobus. White pine. Its range includes Newfoundland, southern and western Quebec, Ontario (except the far northern portion), southeastern Manitoba near Lake Winnipeg, northern and eastern Minnesota, practically all Wisconsin and Michigan, northern Illinois, northeastern Ohio, south along the Allegheny Mountains to northern Georgia, and most of the New England and middle states.

Pinus resinosa. Norway or red pine. Northern range almost the same as that of white pine. Southern range (from east to west) through Massachusetts, northern Pennsylvania, northeastern Ohio, central Michigan, northern Wisconsin and northeastern Minnesota.

Pinus divaricata. Banksian pine (Canada) or jack pine (United States). Of restricted commercial importance, but interesting because the most northern in habitat. Sudworth gives its range as follows: "New Brunswick to New Hampshire and west through Great Lake and Hudson Bay (southern shores) region to Great Bear Lake, Mackenzie River and Rocky Mountains; south into northern Maine, northern New York, northern Indiana and Illinois and central Minnesota." Bell's timber map agrees with above in the northern boundary, but gives the southern limits as passing through Lake Superior and touching the United States only in the northern point of Minnesota and the northern peninsula of Michigan, which is obviously incorrect.

9

Pinus palustris. Longleaf pine. The well known southern longleaf yellow pine. Atlantic Coast region from near Norfolk, Virginia, to Tampa Bay, Florida; west 10 to eastern Texas; north to northeastern Alabama and northwestern Georgia.

7 The Pinus genus. According to Sargent's Silva there are about seventy species, of which one is in the Philippines, twenty-one in the western United States, thirteen in the eastern United States. Only one species grows in the far north; four in the St. Lawrence basin and northern New England; increased to five in the middle Atlantic states, and in the lowlands of the South eight species are found. In Mexico perhaps twelve or fourteen species exist (Vol. XI, p. 2). At least 100 species are believed to have flourished in North America in the Miocene period (Lesq., Rept. U. S. Geol. Survey VII, 72, 83, 17, f 25-33). For insects see footnote 40, p. 11 of Vol. XI, Sargent.

8" Only American representative of a peculiar Old World group of pine trees, of which P. sylvestris (Scotch pine) is the best known."-Silva XI, 68.

See footnote No. 4, page 23.

10" West to the uplands east of the bottoms of the Mississippi River:" in Texas to the Trinity River and to latitude 32 degrees north, and in Louisiana nearly to the northern boundary.-Silva XI, 152, 153.

Pinus echinata (Pinus mitis, Michx.). Shortleaf pine. The shortleaf yellow pine of the South, though not so closely restricted to the South in its range as is longleaf. Found as far north as Staten Island, New York, and ranges all down the coast to Florida; west to southern Missouri, eastern Indian Territory and northeastern Texas. 11 Sudworth does not define its northern limits very closely. Sargent 12 states that it is found in Union and Jackson counties, Illinois, forms large, solid forests in northern Arkansas, Kansas and Missouri and reaches its greatest development in western Louisiana, southern Arkansas and eastern Texas. On the Atlantic Coast known commercially as North Carolina pine.

Pinus tada. Loblolly pine. Oldfield pine. Range from New Jersey to Florida, west to eastern Texas, 13 and north into southeastern Indian Territory, Arkansas, and southern border of middle and western Tennessee. Intermixed with either the longleaf or the shortleaf pine. An inferior lumber wood, used somewhat for turpentining, 14 and the characteristic second growth of abandoned fields and other open areas of the South. Is at its best in eastern North Carolina. Pinus lambertiana. The sugar pine of the Pacific Coast, a valuable lumber wood.15 Found in the mountain regions from Oregon to California, extending back to the head of the McKinzie and Rogue rivers in the former State and in the latter to the Sierra Nevada, Santa Lucia, San Bernardino and Cuyamaca mountains.

Pinus ponderosa. Bull pine. Known commercially as California white pine and also as western yellow pine.16 Ranges from South Dakota and British Columbia on the north to western Texas and Mexico throughout the Pacific and Rocky Mountain region. The most generally distributed tree of large commercial importance in the western mountain region. Pinus monticola. Silver pine. Known commercially as the "western white pine" of Idaho and Montana (with admixture of allied local species). Range from Vancouver Island and southern British Columbia through northern Idaho to northern Montana, having its highest development in these two States; 17 thence southward through Washington and Oregon to Sierra Nevada Mountains in California.

Pinus flexilis. Limber pine. The most valuable lumber wood of central Nevada,

11 Most abundant and attains its largest size west of the Mississippi River. Silva XI, 144. 12 Silva XI, 145.

13" Fifty years ago the low hills in Bastrop County, central Texas, were covered with forests of P. tada, which also spread into the adjacent counties. Extensive lumbering operations were carried on here, all the towns of the central and western parts of the State before the building of the Texas railroads being constructed from timber cut in these pineries, which, however, are now exhausted as sources of commercial prosperity."-Silva XI, 112, footnote 4. The original large trees of the Pamlico Sound region appear to have been of better quality than either the virgin or second growth of today. The average quality is better west of the Mississippi River, and there it is often mixed in with the other lumber pines. Silva XI, 114.

14" Contains large quantities of resin, but it does not flow rapidly when the trees are boxed, and soon hardens on exposure to the weather, and this species is probably not much worked commercially for the production of turpentine."-Silva XI, 114.

15 Attains its largest size in southwestern Oregon. Silva XI, 29. Is largest of the pines. Silva XI, 30. Grows 200 to 220 feet high, and six or eight, or occasionally ten or twelve, feet in diameter. Silva XI, 27.

16 A polymorphous species tending to break into distinct varieties in different localities. Silva XI, 81. "Principal lumber tree of eastern Washington and Oregon, of western Montana, Idaho and the Black Hills of South Dakota, and of western Texas, New Mexico and Arizona."-Silva XI, 81.

17 Sargent is authority for this statement, confirmed by general knowledge and belief.

though knotty and considered inferior to other pines found farther north in its range limits. Ranges in the Rocky Mountain region from Montana to western Texas and New Mexico, and in the mountains of northern Arizona, Utah, Nevada and California.

18

Larix laricina (L. americana 18 Michx.). Tamarack. Not largely used for lumber except in shipbuilding and for rowboats, but widely used for posts, poles and ties. Range from Newfoundland and Labrador to northern Pennsylvania, northern Indiana, Illinois, central Minnesota; next to spruce the most northern species, extending from Hudson Bay northwest to Great Bear Lake and the mouth of the Mackenzie River.

Larix occidentalis.19 Western larch. A larger species than the eastern tamarack and a valuable lumber tree.20 Range from southern British Columbia south in the Cascade Mountains to the Columbia River and to western Montana; also found in the Blue Mountains of Washington and Oregon.21 Picea22 mariana23 (P. nigra Link.). Black spruce. A valuable lumber wood, undistinguished in commerce from the white spruce next described, both being manufactured as "spruce." Range from Newfoundland to Hudson Bay and northwestward to the Mackenzie River; southward in Michigan, Wisconsin, Minnesota, and in the eastern mountains of North Carolina and Tennessee. Both Sargent 24 and Bell agree in including in its range the entire Labrador Peninsula except the extreme northern point and the immediate vicinity of the Atlantic Ocean. Upon Bell's timber map of Canada it and white spruce are platted together as having the most northerly limits of any wood, tamarack coming next; and Sargent speaks of it as “forming, especially north of the fiftieth degree of latitude, extensive forests on the watersheds of the principal streams or in cold, wet swamps; then small, stunted, and of little value." Both these spruces are, however, extensively used as pulpwood in much smaller diameters than would be desirable for saw timber. Picea canadensis (P. alba Link.). White spruce. As to commercial uses see remarks under black spruce above. Northern range same as black spruce according to Sudworth and Bell, though they do not agree on the limits, as see above, except that Sudworth gives it as extending to Alaska and the black 18 Sargent prefers L. americana.

19" When it has grown under the most favorable conditions, on low, moist soil, at elevations of between 2,000 and 3,000 feet above the sea level, the western larch often arises to the height of 250 feet, with a trunk from six to eight feet in diameter; on poorer soil and exposed mountain slopes it has an average height of about one hundred feet, with a trunk two or three feet in diameter."-Silva XII, 11.

20 Especially for interior finish. Silva XII, 12.

21 Its home is in the basin of the upper Columbia River. Silva XII, 12. The great thinness of its bark unfits it to resist fire, and, being a poor seeder, it is becoming reduced in quantity. Silva XII, 13.

22 Picea. There are sixteen known species, seven in North America, one of these in the Appalachian Mountains, two in the Rocky Mountains, one on the northwest coast, one extending to Bering Sea in the far north, and one extending from the east to beyond the Rocky Mountains. The spruces are believed to have inhabited Europe during the Miocene period. -Silva XII, 20.

23"In the United States it is most common and grows to its largest size in the territory adjacent to the Great Lakes, where, however, it is nowhere abundant, thriving only in the moistest situations and rarely producing trunks a foot in diameter. It is far less abundant than the red spruce in all the Appalachian region, and everywhere east of the Allegheny Mountains is a small and comparatively rare tree. It is probably rarely used, except in Manitoba and Saskatchewan, for other purposes than the manufacture of paper pulp."-Silva XII, 31. 24 Silva XII, 30.

spruce as extending only to the Mackenzie River. Sargent agrees with Bell on its range including Labrador Peninsula to Ungava Bay. Southern range to northern New York, Michigan, Wisconsin, Minnesota, South Dakota, Montana and British Columbia. Sargent also specifically includes Maine 25 and northeastern Vermont, as Sudworth does by inference.

Picea engelmanni. Engelmann spruce. Range, northern Arizona and through the Rocky Mountain region to British Columbia. Sargent says that it is largely manufactured into lumber for the construction of buildings and is also extensively used for fuel and charcoal. The wood is very light and stringy,

but not soft.

Picea sitchensis. Sitka spruce or tideland spruce.

Known also commercially as western white spruce. One of the prominent lumber woods of Washington and Oregon. Range in the Pacific Coast region from Alaska 26 to northern California.

Tsuga 27 canadensis. Hemlock. Important commercially because of its wide distribution and its especial adaptation for the coarser building materials on account of its strength and durability.28 Range from Nova Scotia westward through southern Quebec and Ontario to Minnesota, through Wisconsin, Michigan and southward along the mountains to northern Alabama and Georgia.

Tsuga caroliniana. Carolina hemlock. A local southern species closely allied to T. canadensis, formerly considered a variety of the species, occurring in the same forests and farther south than the range of the T. canadensis, and undistinguished commercially.20 Range mountains of southwestern Virginia, western North Carolina, and northern Georgia; very local.

Tsuga heterophylla. Western hemlock. Of larger growth 30 than the eastern species and a better lumber wood, though not yet very largely used. Range from Alaska 31 to Idaho and Montana and southward in the mountains to California.

25" Occurring very close to the shore, where it is bathed in the spray of the ocean."-Silva XII, 38.

26 In Alaska"occurring at the sea level often to the height of more than a hundred feet, and ascending to elevations of three thousand feet, but decreasing in size as it ascends or leaves the neighborhood of the ocean."-Silva XII, 156. It is the principal lumber manufactured in Alaska." -Silva XII, 57. The greatest of all spruce trees, this inhabitant of the northwestern coast is surpassed by few others either in thickness or height of stem."-Silva XII, 57.

27 Tsuga. Seven species, confined to temperate North America, and eastern and southern Asia. In North America two species east and two west. Japan, two species, and the seventh in the Himalaya Mountains. Not greatly subject to insects or fungi in this country. Name is the common Japanese name of the tree (tsuga).-Silva XII, 60, 61.

28 The use of the bark for tanning should be mentioned. "It is estimated that in the year 1887 1,200,000 tons of bark of this tree were harvested; and although a large part of the timber of the trees, cut and stripped of their bark, is allowed to rot on the ground, it is believed that the average annual value of the material of all kinds obtained from the hemlock is not less than $30,000,000."-Silva XII, 66, footnote 3. United States census of 1900 reported a product of 473,222 cords valued at $1,945,452 during the year 1899.

29 Silva XII, 69.

30" Frequently 200 feet in height, with a tall trunk from six to ten feet in diameter."-Silva XII, 73.

31

where it forms with the tideland spruce the largest part of the great coast forest which extends from the sea level up to elevations of about two thousand feet, sometimes one and sometimes the other predominating."-Silva XII, 74.