Historic, archived document Do not assume content reflects current scientific knowledge, policies, or practices. ee Mh, f My) if (i) ¥ ard ; ie bi PN oor Tr \ FOREST RESOURCES Of SOUTHERN MONTANA W. C: Hodge — CW. Brown Ahiii \--Fineh 7 NOCUIGtN & Rocky Mountain Foreét G Range Expcriment @tation eal Missoula Montana Chas.L.Tebbe, Director UNITED STATES DEPARTMENT OF AGRICULTURE FOREST SERVICE STATION PAPER NO. 20 MAY 1949 Prepared by the Division of Forest Economics M. B. Dickerman, Division Chief Statistical and inventory vrocedures were the responsibilitv of P, D. Kemp. Field inventory work was under the supervision of C. W. Brown. Assisting him were W. C. Hodge, T. L. Finch, M. E. Metcalf and E, F,. Peffer. Office computations were made by C. W. Brown, W. C. Hodge, Tf. L., Finch, \. H. Metcaltsandei dev brssoive FOREST RESOURCES OF SOUTHERN MONTANA By W. C. Hodge, C. W. Brown Erol Wo Ihe (salia@la May 1949 Me &* "i, \ - per Ths ’ uM i 4 | The forest survey in Montana... Forest land. CaOPNG Leh Ne ies Timb ic volume e e e e e e e e Lodgepole pine in the Northern Rockies ......... Ponderosa pine saw timber in the semiarid type ..... .e Cottonwood in stream bottom stringer type. . ....-+«. Statistical data by county Table Table Standard 1. 26 Forest land area. Timber volume . statistical data for unit Table Table Table Table Table Table Table Table Table Je 10. Land area bv major use. ..... aialie. Geltenns Forest land area bv economic sLASe. Shier Peo ree Commercial forest land bv species group and stand-size class . e e e e e e e e s e e e Board—foot volume on commercial forest land by species . Cubic-—foot volume on commercial forest land Diy SPECHCSiromemicnne Board-foot volume on hy stand-size class Cubic-foot volume on bv stand-size class Cubic-foot volume on species group, tree size, and class of material commercial forest land and diameter group . commercial forest land and diameter group. . commercial forest land by 11. Average volume per acre by stand-size class . Definitions. Forest survey method ..... Wecuracy, on the data. 5 ss. List of forest survey reports for Montana. ....... ie ‘Oo © THE FOREST SURVEY IN MONTANA A survev of Montana's forests was begun in 1934 as a part of a Nation-wide inventory of the forest resources. Interrupted by the war, this survey was resumed in 1946 and is now about 90 percent complete. Present plans contemplate finishing the survey in 1949 to give Montana the first real measure of its forest wealth. Statistics for 23 counties in Northern and Central Montana and for that portion of the state west of the Continental Divide have been published previously. This report presents basic inventory data on the extent of the forest land and the timber volume for 15 Southern Montana counties as indicated on the map below. These counties were covered by the forest survev in 1948. A survey of South Central Montana is now under way. Upon completion of the survey, a comprehensive report, including data on forest growth and drain, is planned for all of the Montana units. FOREST SURVEY UNITS LRA” AREA COVERED IN THIS RELORT : AREA COVERED 1N PREVIOUS REPORTS Zoe FOREST LAND Southern Montana has over two million acres of forest land, About 10 percent of the area is forested. All of the 15 counties in this southern unit have some forest land. Park County with 705,000 acres of forest has the largest forest - area, Sweetgrass County is second with 270,000 acres. Fallon County with less than a thousand acres has the smallest forest acreage, Within this unit is the principal forested area at the headwaters of the Yellowstone River. The forest area in the eastern portion of the southern unit consists typically of open scattered ponderosa pine stands in the uplands and stringers of cotton- wood along the waterways. Historically these forests provided fuel, shelter, and fence posts for many of the early settlers. As the Northern Pacific Railway pushed west, the forests pro- vided many of the necessary ties and construction timbers. Because of the semiarid climatic conditions the people living in this eastern part have a deep appreciation of trees that is so frequently lacking in more exten- sively forested areas. The western portion of the southern unit contains some of the roughest topography in the state. Granite Peak, 12,850 feet in elevation, the highest point in Montana, towers above this rugged domain. The forests are predominantly coniferous - lodgepole pine and Douglas-fir. Early use of the forest was principally for hewn railroad ties. Nearly every creek draining jiito the Yellowstone shows evidence of work by early day tie- cutters, For scenic beauty the area is outstanding and recreation is big business throughout most of the unit. 10% OF THE TOTAL AREA [Ss EOREST. LAND NON FOREST 3,5 YA OR atic FOREST LAND /S CLASSED AS COMMERCIAL ON- = MMERCIAL 96 Y% OF THE COMMERCIAL FOREST LAND 1S SOFTWOODS¢ 4% |S HARDWOODS SOFTWOODS HARDWOODS ‘ . Sy (i, a 4 . \ re p 1 Meh oh wr ‘ A me, “F ; r A GAN gh rae CoA 2. ee ere he ‘ i ‘ ro : a En See et ee) ‘a TIMBER VOLUME Coniferous timber makes up almost all of the timber volume in the southern unit. From Musselshell and Yellowstone Counties east to the state boundary are scattered stands of ponderosa pine. Juniper is sparsely intermingled with the pine. West of these counties mountain forest types predominate. Douglas-fir, lodge- pole pine, spruce, whitebark pine, limber pine and alpine fir are found throughout this western section. Small stands of hardwood occur throughout the unit along river bottoms. Cottonwood is common to all counties; green ash and box elder are widely distributed in the prairie counties; and aspen occurs along the edges of the mountain forest. Cotton- wood is the only hardwood present in appreciable quantity. Altogether there are slightly more than four billion board feet of saw timber on the commercial forest land. Over three- fourths of the board-foot volume is in saw-timber stands; the remainder is in stands which are predominantly pole-size trees, in open woodland, and as residual volume in very young stands. Four fifths of the board-foot volume in saw-timber stands is in trees 11 to 21 inches in diameter breast high (d.b.h.). Twenty-eight percent of the total cubic- foot volume is lodgepole pine; 26 percent, ponderosa pine; 25 percent, Douglas-fir; 8 percent, spruce; 7 percent, whitebark and limber pine; 3 percent, cottonwood; and 3 percent, miscellaneous species. Juniper is included in the miscellaneous species, but it has a value out of pro- portion to its volume. It is prized as fence post material, and in tourist centers such as Red Lodge souvenirs made of juniper are offered for sale at hand- some prices. The next 3 pages illustrate the kind and quality of timber that is common to the southern unit. SOFTWOOD SPECIES MAKE UP 96 % OF THE BOARD-FOOT AND CUBIC-FOOT VOLUME SOFTWOODS 2 COUNTIES IN THE UNIT HAVE 2/35 OF THE VOLUME cz PARK AND 3 SWEETGRASS Ys OTHER _13 COUNTIES WARE SRECIES MAKE UP 7/896 OF THE BOARD-FOOT VOLUME LODGEPOLE PINE IN THE NORTHERN ROCKIES Pure stands of lodgepole pine are found in all of the mountain ranges west of Billings. The Beartooth and Absaroka mountains have the biggest concentrations of timber in the Southern Montana unit, and a large part of this is lodgepole. These lodgepole stands are usually even-aged, and occur in all stands due to the recurring fires which precede establishment of a pure stand of lodgepole. Shown here is a saw-timber stand about 160 years old. lLodgepole pine, long a favorite of the early-day "tie-hacks" is currentlv in demand for transmission poles and pulpwood. PONDEROSA PINE SAW TIMBER IN THE SEMIARID TYPE Ponderosa pine occurs over much of the eastern section of the southern unit in stands that are frequently broken by rim rocks and grassy mesas. Saw timber such as shown above is found in Carter, Powder River, Rosebud, and Big Horn Counties mainly within the Custer National Forest and the Tongue River Indian Reservation. Ponderosa pine is found also in the Bull Mountain area of Yellowstone and Musselshell Counties. There are over one-half million acres in the unit capable of producing this kind of saw timber. Most of the area is a poor growing site but intermingled with the poor sites are better sites growing trees of larger size and better quality than illustrated above. Lumber production by small saw- mills operating in these forests and producing mostly for local ranch use has been increasing in the postwar years. COTTONWOOD IN STREAM BOTTOM STRINGER TYPE Cottonwood is found in all counties of the Southern Montana unit. 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GOI : uogie) me WW, g OG4°6 > +08°L9 3 Gus (San 8 BGG°G 8 (561, LON : uIOH 3Tg ---e-r-r--cr qoos oTqno hl eee SP lS . mr rc?- - _- yoor paeog W |-e\rrrcroc - Te20], > poompiey : poom4yos : TeO], > poompszeyH = POOMAFOS _: $ 5 Aquno9g fé teqwt4 TIV : /T sequty mes SUNTOA JoqUT], °c eTAel, STANDARD STATISTICAL DATA FOR UNIT SOUTHERN MONTANA Table 3. Land area by major use Major use ; Acres : Percent Forest land 2,436,048 : D9 Nonforest land 1/ 22,209,712 : 90.1 Total 21,645,760 i) leo 0 1/ Includes water areas. Table 4. Forest land area by economic class Economic class i Acres : Percent Commercial forest land : LSS WS 2 W205 Noncommercial forest land : Withdrawn 1/ 37,830 : Other 2/ 631,073 668,903: 27.5 Total Doo 2 100.0 1/ Commercially valuable forest land withdrawn from commercial use for parks, reserves, wilderness areas, etc. 2/ Remote and inaccessible alpine areas, and other land which owing to very low productivity, excessively poor qualitv timber, or extreme inaccessibilitv appears to be nermanently out of the commercial timber producing class, S102 Table 5. Commercial forest land by species group and stand-size class Species group Softwood Saw timber Pole Seedling-sapling Poorly stocked and denuded Total Hardwood Saw timber Pole Seedling-sapling Poorly stocked and denuded Total Total Saw timber Pole Seedling-sapling Poorly stocked and denuded Total and stand-size class 2 Acres 389, 335 836,053 157,366 316,980 IL (OS)S) TV 23,730 33,724 55940 4, O17 67,411 413,065 869,777 163,306 320,997 OMS -ll- 3 Percent Table 6, land bv species Species ene ree Softwood Ponderosa pine Douglas-fir Alpine fir Engelmann spruce Lodgepole pine White bark and limber pine Subtotal Hardwood Cottonwood Boxelder Green ash Subtotal Total 1/ Less than 0.1 percent. Board-foot volume on commercial forest Volume : M board feet : 8). Soi) 1,082,760 61,303 D7 Bye ONS) 1,097,009 200,622 3,988, 280 156,907 Le. 858 159,236 1,147,516 -12-_ Percent wd NOON eee - OS KF AW OwmnwWwnk oO 100.0 Table 7. Cubic-—foot volume on commercial forest land by species Species rie Volume ras zie a Micubacy heeki im encenitim: Softwood Ponderosa pine : 401,815 AX6s,3} Douglas-fir : 382,167 25.0 Alpine fir : 3350 8 Do Engelmann spruce : LAA OI |g 8.4 Lodgepole pine : hPL ZIHO) 27.6 White bark and limber pine : 105,306 : 6.9 Juniper : A igiil 32 Subtotal BWLD 832 96.6 Hardwood Aspen : Use Sinan 3 Cottonwood : 42,745 : Pls) Boxelder : Zeta Nas gil Green ash : D5) iad Subtotal : HLA Cb2 og 34 Total Sahel ORO Ties i RS T8401 Sut[des—sut[ pees aequty mes Wi REGO 8 ~~ SAS°G 8 EGP Est 8 «6 B5O"GOL «=—&§ «6G OSS 8 Wed : = Oe > 2eO le <= €179€ +: pepnuep pue peyo04s AT100g Tov 71 Se ee DS 18019 = SSO Ga: 79° LT9 8 bhi 5S uA TE 68 ONO GE 68) «(tKSCOS 8 eTOd SARA) 5 NOES 8 GESoSoL 8 GIE°SIG 8 SNS ’GGE 8 —------------ = - Ago SECM Gl = = = >See Sa SS ney, OLS C622 Ue ae 8 ee ats Ore ae S TO ezts—pueq4s : SOyoul, dnois deqjewetp Aq oumTop dnois Jejeuetp pue sseTo SzZtS-pueys AQ puel[ 4SetOgy [LeToOLSMUO UO SUNMTOA YOOJ-OTAND °6 STqeI, OG UE 8 eee > §99¢°699 2 Gor mG S T27°6ET : = : 199°6 > LS8*6er 148 °9¢ : - ett iil 5 OWS 018° LTL : 6st zc OS > 471¢°SS9 WHESSE?SG 2 GI WE > 6047 ° 86S s 4700-679 -¢ --------- - SS Gio Oi = = a SS Se ey oe 0 Oveenc oma OG ee ee Oe oe Te90L : SOuoUlL dnois dejewetp Aq oump[o, rt re : Te4O0], : pepnuep pue peyoo ys AT100g : SutTdes—suT [pees g aTOdg : Jequty mes : SSW[O ezts—pueqs Shaan 2h ann SRN RIDE dnois Jejewetp pue Sse o Szts—pueqys Aq puel ySetOfy TeTOTSUMIOD uo suMToOA yoOoJ-pseog °8 STAR] cr ee er eo yrs 5 fa 2 ears Table 10. Cubic-foot volume Cubic-foot volume on commercial forest land by species group, - species group, tree size, and class of meterial Tree size and ; Volume bv species group class of material oP Eee Ri tore net Wu cE Not a sd cia) NR ad : Softwood : Hardwood : Total --c- fc coc M cubic feet - ----- Saw-timber trees Sawlog portion 1/ 675,016 25,255 700,271 Other 2/ : IIe Weg IBS) g 131,350 Subtotal UBT 37,824 831,621 Pole trees 3/ 682,035 ; ah TANS 696.153 Total 1,475,832 51,942 > iL Sag Tale 1/ Sound trees only. 2/ Upper stems of sound trees, usable volume of cull trees, and limbwood of hardwood species. 3/ Sound and cull trees. Table 11. Average volume per acre by stand-size class Average volume per acre Board feet : Cubic feet Stand-size class Saw timber : 7,900 2 1,996 Pole : 825 - 710 Seedling-sapling : 164 : 88 Poorly stocked and denuded =: 43h 8 222 All stands é 2 sinil : 865 =15= DEFINITIONS Following are definitions of terms used in this report: Area Classes Forest land is land bearing forest growth or land from which the forest has been removed but which shows evidence of past forest occupancy and which is not now in other use, Commercial forest land is forest land bearing or capable of bearing timber of commercial character and economically avail- able now or prospectively for commercial use and not withdrawn from such use. Noncommercial forest land is (1) commercially valuable forest land actually withdrawn from commercial use for parks, re- serves, wilderness areas, etc., and (2) remote and inacces- sible alpine areas, and other land which owing to verv low productivity, excessively poor qualitv timber or extreme in- accessibility appears to be permanently out of the commercial timber-producing class. Softwood forest consists of stands with 25 percent or more of ponderosa pine or 50 percent or more of other coniferous species. (Based on cubic-foot volume. ) Hardwood forest consists of stands with less than 25 percent of ponderosa pine and 50 percent or more hardwood species. (Based on cubic-foot volume. ) Stand=-size Classes Saw-timber stands include stocked areas with a plurality of the total net cubic volume in trees 11.0 inches and larger in diameter and generally with 2,000 board feet per acre or more in saw-timber trees. Pole stands include stocked areas in which a plurality of the total cubic-foot volume is in trees from 5.0 inches in diameter to saw-timber size. Seedling-sapling stands include stocked areas in which the pluralitv of the total cubic-foot volume is in trees less than 5.0 inches in diameter. Poorly stocked and denuded stands include areas with less than: (a) 2,000 board feet per acre, (6) 10 percent stocking of pole trees, and (c) 10 percent stocking of seedling-sapling trees, SG FOREST SURVEY METHOD A. The forest resource statistics in this report are based on a field survev made during 1947. Briefly the method used in making this survey was as follows: 1. The forest area was determined by an area sampling system which involved measuring and classifying systematically distributed sample segments. 2. The timber volume was determined bv measuring the trees found on randomly selected one-fifth acre plots located within the sample segments B. The basic data from which the area and volume were determined con- sisted of the following field samples: : Area : Volume :Number of: Area per : : Area per Class : sample :sample segment:Number of:sample plot :segments : acres : lots : (acres ic 234 2,560 702 1/5 ete Ge tol 193 640 382 1/5 C. Distribution of the area sample segments and volume plots was con- trolled by the following method: 1. The entire area was divided on l-inch-to-the-mile base meps into three primary classes: Class I Areas vredominantly forest for which aerial photographs were available. Class II Areas predominantlv nonforest for which aerial photographs were available at moderate cost. Class III Areas predominantly nonforest for which aerial photographs cost more than $2 per PEIN Om HOT whch sunereWwercemoOmacr als photographs. 2. Hach of the three primary classes were further subdivided into units in the following manner: Beginning with a random selec-— tion, Land Office section corners were marked on a base map at 4-mile intervals for areas in Class I, 7-mile intervals BGs for areas in Class II, and 10-mile intervals for areas in Class III. Thus, the three classes were subdivided into units containing approximately 16, 49, and 100 square miles respectively, each unit centered on one of the section corner control points. 3. The control points were transferred to aerial photo index maps from which photographs were selected to give photo coverage for a segment of each unit containing forest land. For Class-I units the sample segments consisted of four Land Office sections (2,560 acres) centered on the control point, for Class-II and -III units the sample seg- ments consisted of one section (640 acres) lying northeast of the control point. 4, All sample segments containing commercial forest land, in- cluding those with doubtful forest cover by photo in- terpretation and all sample segments without aerial photo- graphs, were examined and mapped in the field. For each sample segment the forest cover was stratified by com- mercial character, forest type, stand-size, stocking, age, and site classes. The area of these stratifications was determined for each mapped sample segment and as refined by line transects was multiplied by sample factors (the area of a class divided by the area sampled in that class) to get the total area by forest condition classes. 5. Timber volume was tallied on three 1/5-acre sample plots in each sample segment of Class I, and two 1/5-acre plots in the sample segments of Classes II and III. The plots were randomly located within the sample segments. Plot volumes when averaged for a given forest condition were multiplied bv the area to determine the total timber volume. ACCURACY OF THE DATA In determining the extent of various cover types and stand-—condition classes, there are two possible sources of error: (1) errors in classifving the cover of the field samples and in compiling the field data, and (2) sampling errors. The former result from mistakes of judgment or technic and the complexity of the cover which not in- frequently grades from one class into another with no clearly defined boundaries. These errors were minimized bv the exercise of care and skill, but it is seldom possible to evaluate them. An effort was made to maintain a high order of accuracv and uniformity of standards in the classification, collection, and compilation of sample data, by field checks, by a continuing program of training, and bv cross checks 39, Gla) OrrieaL@e)o Eee j WD) Pe] Met a Sampling errors (standard errors of estimate) on the other hand do not involve human errors but rather are theoretical measures of the reliability of estimates based on the variability exhibited by sample measurements. They generally vary inversely with the square root of the number of samples and directly with the square root of the unsampled proportion of the total population. Hence, they can be controlled by altering either the number of samples, the size of individual samples, or both, Analysis of sample variations indicate that the standard errors of estimate for the unit as a whole are + 3.5 percent for total forest, 25a percent for commercial forest, and = 6.6 percent for noncom- meretal forest. Accordingly, the probabilities are 2 out 3) that the actual forest, commercial forest, and noncommercial forest land areas are, respectively, within + 85,000, = 90,000, and + 44,000 acres of the estimated areas if measurements and computed errors introduced no bias. In determining timber volumes, the possible sources of error include in addition to those cited above (3) inaccurate measurement of sample plots, tree diameters, tree heights, and cull, and (4) bias resulting from improper construction, selection, and use of tree-volume tables. All reasonable effort was made to eliminate errors from these sources. The standard error of the board-foot volume estimate for the block as a whole is + 7.8 percent and of the cubic-foot volume estimate, = 6.8 percent. Accordingly, the probabilities are 2 out of 3 that the actual volumes are within = 324,000 M board feet and = 104,000 M cubic feet of the given estimates. The reliability of one statistic as compared with another presented in the same or a related table can be judged roughly by its relative magnitude. In general, the larger quantities warrant greater con- fidence; the smaller quantities indicate only relative magnitude. This fact should be borne in mind in considering the small quantities associated with many of the counties covered in this report. A1@= tay Oy wins 7 a i ae A © a Meer. Et Zz oma I sue ww [5 10 tab 2 13 14 15 16 7 18 20 Pals IZ 13 20 LIST OF FOREST SURVEY REPORTS FOR MONTANA Forest Survey Statistical Service Series Forest statistics for Lincoln County, 1941. Forest statistics for Flathead County, 1941. Forest statistics for Lake County, 1941. Forest statistics for Sanders County, 1941. Forest statistics for Mineral County, 1941. Forest statistics Highlights Highlights of of County (west Highlights of (west of the Highlights of (west of the Highlights Highlights Highlights Highlights Highlights Highlights 1943. of of of of of of the the for Ravalli County, 1941. Missoula County forest situation, 1942. forest situation in Lewis and Clark of the Continental Divide), 1942. the forest situation in Deerlodge County Continental Divide), 1942. the forest situation in Silver Bow County Continental Divide), 1942. the the the the the the Powell County forest situation, 1942. Granite County forest situation, 1942. forest situation in western Montana, 1943. forest situation in Chouteau County, 1943. forest situation in Fergus County, 1943. forest situation in Judith Basin County, Highlights of the forest situation on the national forests of western Montana, 1944. Forest Survey Releases The forest situation in Lincoln County, July 1943. The forest situation in Ravalli County, July 1943. Station Papers Forest resource statistics Cascade County, by H. J. Pissot and E. F. Peffer, April 1948. Forest resources of Northern Montana, by C. W. Brown and W. C. Hodge, June 1948. Forest resources of Southern Montana, by W. C. Hodge, C. W. Brown and T. L. Finch, May 1949. E202 Station Paper _ No. 1 10 ae 12 13 14 15 16 LIST OF PREVIOUS PUBLICATIONS IN THIS SERIES * A preliminary study of root diseases in western white pine, by John Ehrlich. Oct. 19359. * Possibilities of partial cutting in young western white pine, by E. F. Rapraeger. Jan. 1940, Blister rust control in the management of western white pine, by Kenneth P. Davis and Virgil D. Moss. June 1940. Possibilities of wood-pulp production in the northern Rocky Mountain region, by E. F. Rapraeger. Mar. 1941. Results to date of studies of the durability of native woods treated and untreated, by C. N. Whitney. Rev. Jan. 1946. Changes in Benewah County forest statistics, by Paul D. Kemp. July 1947. A guide for range reseeding on and near the national forests of Montana, by C. Allan Friedrich. Oct. 1947. Pole blight - a new disease of western white pine, by Ce. A. Wellner. Nov. 1947. Management practices for Christmas tree production, by Ce A. Wellner and A. Le Roe. Nov. 1947. The merits of lodgepole pine poles, by I. V. Anderson. Nov. 1947. Tables for approximating volume growth of individual trees, by P. D. Kemp and M. E. Metcalf. Mar. 1948. Forest resource statistics, Cascade County, Montana, by He J. Pissot and E. F. Peffer. Apr. 1948. Forest resources of northern Montana, by C. Wl. Brown and W. Ce Hodge. June 1948, List of publications available for distribution or loan, 1910 through 1947. NRM station. June 1948 Review of published information on the larch-Douglas fir forest type, by Russell K. LeBarron. Nov. 1948. Development of a blister rust control policy for the national forests in the Inland Empire, by Donald N. Matthews and S. Blair Hutchison. Dec. 1948, Out of print. Loan copies may be obtained upon request. Station Paper No. a7, Disintegration of girdled western hemlock and grand fir, by Austin E. Helmers. Dec. 1948. 18 Suggested Montana Douglas-fir Christmas tree standards, by S. Blair Hutchison and Ben M. Huey. Jan. 1949. 19 The possibilities of modifying lightning storms in the Northern Rockies, by Vincent J. Schaefer. Jan. 1949.