$>q* ±7* v * --' V ' **'$* . *$W»* Mfc&ViJfo*£;£:- CORNELL UNIVERSITY LIBRARY BOUGHT WITH THE INCOME OF THE SAGE ENDOWMENT FUND GIVEN IN 1 89 1 BY HENRY WILLIAMS SAGE ALBERT R. MANN LIBRARY New York State Colleges of Agriculture and Human Ecology AT Cornell University CORNELL UNIVERSITY LIBRARY 924 081 089 066 Cornell University Library The original of this book is in the Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924081089066 THE WILLOW FAMILY OF THE GREAT PLATEAU BY MARCUS E. JONES, A.M. ISSUED MARCH 9, 1908. THE DESERET NEWS Salt Lake, Utah Y> INTRODUCTORY. This work, on the western willows, is put forth tentatively in or- der to clear up some doubts and to direct the attention of field bot- anists to the willows which heretofore have been difficult to identify because of not being described in compact shape, for the descriptions have been so scattered and so contradictory as to be very confusing. It is evident that the stipules as a rule are of little value for iden- tification. The color of the twigs and leaves in herbarium specimens is value- less. Many willows are said to dry black, but they do so only when neglected in the press, some drying black earlier than others only. The color of the twigs is lighter in summer than in spring as a rule. Shade and sunshine also make differences in the same species. The male and female twigs often differ from each other and this has led to much poor identification. It is very desirable to get the colors of the twigs of both sexes of each species in various situations of ex- posure and altitude. It is very desirable to get the changes of color in the scales of the male and female catkins; to determine if the sex color differs perma- nently in the scales of each species, and what variation there is in each species. It is very desirable that where possible willows should be tagged when the flowers are gathered so that mature leaves can be gathered later from the same place, since the flowering leaves often differ from those that come out later. Life Zones. The life zones as used in this paper were given in my Contribu- tions and my Geography of Utah. They are as follows : Frigid, cor- responding to the Arctic and treeless regions above timber line on the mountains; Upper Temperate, corresponding to the range of the spruce and fir, aspen for the most part, and practically all of the region above the range of Artemisia tridentata, and Quercus Gam- Ijelii and the burr oak; Middle Temperate, corresponding to the range of the deciduous oaks, and whose upper limit is the upper limit of Artemisia tridentata and the beginning of the trees given above; Lower Temperate, corresponding to the range of the pinon and desert juniper, and live oaks of Arizona, and whose upper limit is about that of the apricot and peach though a little lower, and whose lower limit is that of Artemisia tridentata, and the begin- ning of Larrea; Tropical, corresponding to the range of Larrea, Plu- chea, Chilopsis, Martynia, etc. For those who use the terminology of Merriam it should be said that the classification given here much an- tedates his, having been given by Humboldt many years ago in gen- eral, the subdivisions are my own. Merriam's "Sonoran" is my Trop- ical, his "Upper Sonoran" is my Lower Temperate, and has no rela- tion to the Sonoran botanically as there is a greater break in the flora between the Tropical and Lower Temperate than in any other zone. Merriam's "Transition" is my Middle Temperate, and there is less transition in it than in the next zone above it, his is an inappro- priate name. The rest is his "Boreal." This is also an inappro- priate name, applying only to the northern Upper Temperate Life Zone instead of to both northern and southern as mine does. The Willow Family of the Great Plateau. WILLOW FAMILY. SALICACEAE. Lindley Nat. Syst. Ed. 2 186 (1836) Dioecious shrubs or trees with alternate, mostly deciduous, not lobed leaves ; stipules mostly present ; flowers all in catkins which are mostly terminal or terminating short and lateral branches and mostly opening before the leaves, each flower be- ing subtended by a membranous bract and without a. calyx ; stam- ens one tp many op filiform filaments ; ovary i-celled with 2 stig- mas and 2-4 parietal placentae and many small and hairy-tufted seeds; pod 2-valved; anthers 2-celled and opening ■ lengthwise ; wood white, soft and light in weight ; bark bitter and tonic, very good for debility, fevers and liver troubles ; twigs and wood most- ly brittle. A family of 2 genera and 200 species, most abundant in the Temperate Life Zones, growing mostly near water. The wood is everywhere used for kindling and for making the high- est grades of charcoal, it is. occasionally made into lumber in the larger trees, but none, but the cottonwoods grow large enough for lumber as a rule. The willows especially are used for poles and for brush fences everywhere and the twigs are much used for bas- ket work and matting. All species are rapid growers. Key to Genera. 1. Floral scales entire; not resinous; flowers with small glands and no disks; stamens not over 5; buds with a single scale; catkins not resin- ous ; leaves mostly narrow, never wider than long, simply pinnate-veined; mostly shrubs; pods small, ovate or narrower, 1-3 inches long. 1. Salix. 2. Floral scales lacerate; flowers with a large or cup-shaped disk; .stamens many; buds With several mostly resinous scales; catkins mostly resinous, leaves mostly broad, often broader than -long and often rhom- boidal, with branched nerves; pods rather large, mostly nearly globose, and mostly about i inch long; all are trees and often very large. 2. Populus. SALIX. Willow. Tourn. L. Syst. (1735), Gen. 300, Sp. PI. 1015. Each flower with 1-2 small glands at base; stigmas short; branches mostly round.. The pubescence of thjEJ scales^and pods is variable ; the stipules vary greatly and are not good for spe- cific distinctions. A genus of about 175 species (Salix, the Latin name for willow). Key to Species. A. Stamens 2. (except in S. fragilis).' AB. Cultivated trees. Leaves wider above. Leaves wider below. Stamens 5, leaves long pointed. J. S. alba. 2: S. Babylonica. 3. S. fragilis. ABB. Scales dark-tipped; catkins not coming out after the leaves. ABBC. Pods smooth. ABBCD. .Leaves entire; not alpine nor sub-alpine. 4. S. prolixa. ABBCDD. Leaves serrulate or finely toothed (entire in a few. forms), normally acute. ABBCDDE. Leaves not wider above, normally glaucous ■'-. below. Leaves with tapering apex. 5. ; S. cordata. Leaves often acute but not acuminate. 6. S. balsamifera. ABBCDDEE. Leaves evidently wider above, often acute, but not conspicuously acuminate; styles , evident. , Leaves green on both sides, not glaucous. 7. S.' Novae— Angliae. Liaves glaucous or pubescent below. Leaves not pubescent below; pods nearly sessile; catkins sessile. Leaves nearly linear; stipules small or none. 8. S. irrorata. Leaves oblanceolate to obovate; sti- pules conspicuous and persist- ent; styles long. p. S. fnonticola. 'Leaves, pubescent below at least when young; pods not sessile; styles about as long as the stigmas. .-.*.■; ;■ .1;'. v.--,. 10. v S. lasiolepis, ABBCC. Pods pubescent. A BBC CD. Not low alpine nor sub-alpine shrubs. ABBCCDE-, Styles very_s\ort or.none; pods woolly; leaves broader above ihe^^jniddte, r ii. $. Scouleriana. ABBCCDEE. Styles longer than^ the stigmas. (Scoul- eriana would be_ sought her.e when the styles are long). ■ 'V.. ■ Leaves silvery-silky or woolly below only when young; catkins appearing with the leaves, large and many flowefed'f- twigs not yellow. 12. S. Lemmoni. Leaves at least minutely silvery-silky below; catkins small, appearing, before the , leaves and without persistent bracts. ''■-' . .. & . 13. S. glaucops. ABBCCDD. Low alpine^ or arctic! or sub-alpine plants, not over a few feet high. ' ABBCCDDE. Stems not prostrate, mostly erect in ABBCCDDEF. Pods smooth; catkins thick, dense- ly flowered, linear (except in Wolfii) ; styles elongated."-' Catkins coming out before the leaves, sessile and without' persistent bracts. 14. S. Tweedyi. Catkins coming out with- the leaves on leafy peduncles {Richardsonii might be s'ought here). •'■■"'- Catkins large on rather long penduncles, with . large leaves.' '< ' ' 15. S. Barclayi. Catkins small 'on' short peduncles over-topped -' by the relatively large leafy bracts. 16. S. Wolfii. ABBCCDDEFF. Pods puberulent, but not silky vil- lous; catkins coming out before the leaves, and^sessile ; densely flowered and linear; styles elongated; plants a foot_ or two high; leaves smooth and green; prctic plants. Pods sessile, shortly acuminate; stipules narrow- ly iu'Hceolate, not large; leaves with revolute margins; twigs thick. 17. S. Richardsonii. Pods'ibng-beaked; short-pedicled; branches r - slender. " " ' • 18. S. fulcrata. ABBCCDDEFFF. Pods silky or woolly. . ' ABBCCDDEFFFG. Catkins sessile, coming out before the leaves and without persistent leafy bracts; styles elongated; pods about ■ sessile. ''• '■ ■"■' '• CatkiM nearly 3 inches long, thick; twigs thick. 8 /p. S. Barrattiana. Catkins small, from nearly globose to i inch or so long; twigs smooth, chestnut col- ored; stipules none. 20. S. chlorophylla. Catkins 3-4 inches long, thick; twigs yellow- ish-woolly. 21. S. speciosa. ABBCCDDEFFFGG. Catkins seldom 1 inch long, on short, leafy peduncles, and com- ing out with the leaves; leaves paler be- low. Leaves 1-2 inches long, entire, oblanceolate to elliptical and acute at both ends, deciduously silky. Catkins oval to -oblong, hardly as long as the bracts <(S. WolAi var. pseudo- lapponum comes here). Catkins linear, densely flowered. 22. S. glauca. Leaves 2-4 inches long, glandular-serrulate, mostly silky-'aillous ; catkins large and linear. 23. S. Californica. ABBCCDDEE. Stems prostrate or low and matted, a few inches high, alpine and arctic, mostly with subterranean twigs, leafy at the tips; leaves evergreen, leathery and reticulate ; catkins most- ly terminal y and tyafy bracted; styles elongated. ABBCCDDEEF. Pods about sessile. ABBCCDDEEFG: Leaves entire. ABBCCDDEEFGH. Leaves smooth or only ciliate; scales obovate. Leaves inclinred to be narrowed at each end;,, last year's twigs angled; cat- kins long peduncled, linear, many flowered. 24. S. Brownii. Leaves ohlong-obovate and shortly ac- uminate or almost obtuse, 1-4 inches long, very much smaller than the above; catkins not over I-? inches long. 25. S. Anglorv ABBCCDDEEFGHH. Leaves..-: sr pubes- xrent; catkins about two inches long and many-flowered; pods long-silky; leaves about 2 inches long, a little revolute. 26. S. artica. ABBCCDDEEFGG. Leaves glandular-serrulate, obliquely pointed ; not lighter below; catkins linear; densely flowered except below. 27. S. Myrsinites. ABBCCDDEEFP. Pods distinctly pediceled; ashy; ■-'" catkins not' terminal, linear and densely flower- ed; leaves obovate, smooth, margins serrulate. , 28, , S. Chamissonis. ABBB. Pistillate scales (at least) ,- not black, J ex'cepV in S. petiolaris, mostly yellowish or rarely reddish, catkins peduncled and leafy bract ed, or terminal ■ on' short leafy branches (sessile in S. Drummondiana). ABBBC. Low alpine or arctic plants; pods not long-stipitate (S. myrtilloides has a long stipe and is not alpine nor arctic). ABBBCD. Herbaceous branches Very short, about 1 inch above 'ground; leaves from round and notched at both ends to oblong-elliptical, smooth, shining, prom- inently veined; catkins short ! loosely 3-9-flowered, with 2-3 bracts; style evident. Catkins' terminal; pods smooth: 1 Catkins' with' two normal leaves which are longer than they ark; leaves with ctenulafe' margins. '- 29: S. herbacea. Leaves entire; pods very shortly pediceled and with ' very short style. '■ ■'"■'' 36. S. rotundifolia. Catkins sometimes lateral, oval; pods variably white- woolly, rarely smooth. 31: S. polaris. ABBBCDD, Shrubby plants. ABBBCDDE. Leaves very obtuse above and rounded (excipt S. reticulata var: nivalis). '■■■'■ ABBBCDDEF. Nearly prostrate plants a few inches •'■ -"high, with subterranean trunk; leaves entire, ' ' paler below; catkins long-peduncled, linear, terminal; p-ods ovate; white-woolly ; styles 2- cleft or none. Leaves inclined to be wider above and obtuse, rugose; petioles half the blade; styles very short; scales hairy below (except in the va- riety) 32. S. reticulata. Leaves mostly round, the petiole often equaling . the \ blade, , closely net-veined below, rather revolute; catkins densely flowered; scales smooth; styles none. 33. S. orbicularis. " ABBBCDDEPF. Shrubs with trunks a foot or two high, with widely spreading branches run- ning over, the ground. (S. Chamissonis might be sought here). Leaves smooth or soon so, paler below; catkins . lateral. 3§. S. ovalifolia. Leaves silvery-silky below, nearly 2 inches long, catkins short-peduncled and bractless, but 10 . terminal on short leafy branches of the sca- . . son - 35- S. vestita. ABBBCDDEE. Catkins lateral on leafy peduncles; leaves acute on both ends. (S. . Brownii var. ■fenera would be sought .here). Styles elongated and pods nearly sessile.. 36. ■ S. phylicoides. Styles very short; catkins slender and sparsely flowered; . pods long-stipitate ; , scales oblong, snuopih. or (ong-ciliate. ■ , ,,. 37. S. myrtilloides. ABBBCC. Shrubs, a few feet high, sub-alpine ; branches mostly erect or not decumbent; scales broad. ■ . ABBBCCD. Leaves narrow but not linear, yiidrib conspicu- ous, and yellow; pods, , sessile -or nearly so. Leaves, not revolute, entire, thinly-straight-hairy on both sides; stipules minute; catkins about 1-2 inches long-,; pods sessile. , . ... . 38. S. desertorum. Leaves revolute, remotely denticulate, loosely woolly above, and densely so below; stipules about as long as short petiole; catkins closely flowered and the fertile, ones at least two inches long; pods short- ' stipitdie. .',.', 39.\ S. Candida. ABBBCCDI). , Leaves obovate, broad; pods evidently stip- itate. . ;■_,.,.■■',, ,40. S. Drummondiana. ABBBCCC. Slender shrubs or trees 10 feet or more high, not alpine nor sub-alpine., ABBBCCCD. Leaves a trifle wider above, not linear, paler below, sparsely pubescent, variably silky when young; catkins coming out 1 with the leaves and leafy bracted; pods acuminate and. long-stipitate; styles short; fer- tile scales narrow; plants of the Middle Temperate Life Zone. ABBBCCCDE. Leaves acute, mostly obtuse at base, slender-petioled; catkins narrow and longer 'than the bracts. Leaves' thin and entire when young, pale; fertile cat- kins peduncled and .with large, leafy bracts; scales, yellow. 41 S. rostrata. Leaves sharply serrulate, glaucous below; catkins nearly sessile with a few short, leafy bracts; scales black tipped and yellowish below. 42. S. petiolaris. ABBBCCCDEE. leaves narrowly oblanceolate and acute at both ends, very short-petioled, entire, 1-2 inches long; fertile catkins oval or broadly oblong, 11 barely surpassing the bracts, almost sessile, 6-9 lines long. . . , ,.,<•,- 43. S, macrocarpa. ABBBCCCPD. Leaves Jin'ear or nearly so, fertile catkins '-. ,; . ,. coming out after the leaves on leafy branches; scales from linear-lanceolate , to broadly-oblanceolate, but narrow and long (rhomboidal in taxifolia), yellow- ish, smoothish above'; plants of the Tropical, and " lower Temperate ,Life Zones. Leaves inclined io be remotely denticulate';' one to four ,/. ■ inches long; catkins mostly lirtear and -mostly many flowered. -.■;. ... ..:...-■, 1 1 44.' • S. longifolia. Leaves ...linear; and, about 1 inch long, "very many; catkins nearly globular, seldom over 10-flowered; scales in- ■ dined to clasp the pod. ■■■■'■■".. .:•.'.- i.r .' . v..' 45- . S. taxifolia, • AA. Stamen I; anthers-black; scales reddish with, .rather dark tip; native $hrub$: .1 ,...;.*•* ;;■ r. _ '.>;,.- 46. S. pellita. AAA- Stamens mostly 5, not 2; scales' yellow, very thin, not darker above; all catkins coming out "with the leaves and leafy-bract ed; trees or tall shrubs with bark rough below; pods smooth and stipitate; none alpine nor sub-alpine, mostly growing in the lower Temper- ate and Tropical Life Zones; natives., ,, AAAB. Petioles not glandular War viscous;'' catkins long-peduncled, linear (broader in' S. lasiandra). AAABC. Leaves thin, linear to linear-lanceloate and tapering from near' the base to a long acumination ; petiole 2-4 lines long. Leaves lighter below; internodes slender. 4f~. . S. nigra. ,j Leaves Hot lighten-below,, very slefider and tapering; in- ternodes shorU'.i '■..., ■•■/ 48. S:. Humboldtiana. AAABCC. : Leaves narrowly* elliptical to oblong lanceolate, vari-, ably glaucous below, rather shortly-acumi/rtaie ; pods ovate, about 1 line long. . , ■, . Leaves thin, smooth on both sides and including the 6-9 line long petiole. 49. ''S. amygdaloides. Leaves leathery, not thin, with short, downy petioles and often silky when young. ' 50. S. laevigata. AAABCCC. Leaves liriean-elliptical, shortly acuminate, remotely denticulate, on short and stout and woolly petioles; very glaucous below: 3 . ,i Si- S. Bonplandiana. AAABB. ' Petioles glandular or viscous and often with raised glands near the top;; shrubs 10-20 feei high, tufted and erect; catkins thick;. -growing in the middle Temperate Life Zones along streams. '■• . ■ <:'. 12 Leaves from ovate to lanceloat&, rather rounded at base; catkins short-peduncled. 52. S. lucida. Leaves acute at base; catkins long-peduncled, large. 53. S. lasiandra. A. Stamens 2 (except in S. fragilis). AB. Cultivated plants, all trees; pods smooth; leaves narrow and acu- minate at both ends, sharply serrulate. 1. S. alba L 1021. White Willow. (alba, white). Leaves lanceolate, mostly larger above the middle; branches not conspicuously drooping. Occasionally planted throughout our region. 2. S. Babylonica L. 1017. Weeping Willow. (Babylonica, Baby- lonian). * Leaves largest near the base and then long-acuminate, nearly linear; often coiled; branches very slender and drooping. Very common in cemeteries. 3. S. fragilis L. 1017. Brittle Willow, (fragilis, brittle, frail). Stamens 5;^ pods' lanceolate, much longer than the pedicels, smooth; leaves lanceolate and long-acuminate; scales deciduous; twigs brittle at base. Occasionally cultivated in Colorado, etc. ABB. Native species; scales ddrk-Hpped; catkins not coming out after the leaves. ABBC. Pods smooth; not alpine nor sub-alpine shrubs.- ABBCD. Leaves glaucous below and smooth, entire; pods long-stipitate; catkins coming out with the leaves and leafy-bracted, sparse- ly flowered; styles almost none; branches slender; low shrubs 1-3 feet high, growing in bogs. 4. S. prolixa And. Mon. Sal. 94 (1867). Long pediceled Willow. (prolixa, much-produced). Catkins short-peduncled/ the fertile ones 2 inches long and very sparsely flowered; scales of staminate flowers densely white-hairy; pods ovate-donic, strongly beaked, 2 lines long, on a pedicel longer than the scale; leaves obovate-lanceolate, acuminate; green' stipules 2-3 times shorter than the petioles. This grows near the boundary of Montana, in British America, and northward. ABBCDD. Leaves serrulate or finely toothed (entire in some forms), normally acute. ABBCDDE. Leaves normally glaucous below, not wider above the middle; pods stipitate; styles short; catkins coming out before the leaves; slender shritbs about 10 feet high. 5. S. cordata Muhl. Neue Schrift. Ges. Nat. Fr. Berlin 4 236 t 6 f 3 (1803.) Heart-leaved Willow. Common Willow, (cordata, heart- shaped referring to the base of the leaf). Leaves acuminate, often falcate, mostly cordate at base, oblong- lanceolate, sharply glandular-serrulate; stipules normally large and persistent, pods in the type short-stipitate, narrowly-ovate; branches brown. Common in the Middle Temperate Life Zones. Much used for brush fences and kindling wood. 13 S. cordata var. Watsoni Bebb Bot. Cal. 2 86 (1880). S cordata var. lutea Bebb. Yellow-twigged Willow. (Watsoni, Watson's). S. padophylla Rydberg, S. flava Rydberg. Branches smooth and yellow; leaves oblong and- short-acuminate, obscurely serrulate, 1-3 inches long; catkins about 1 inch long. This grows on both sides of the Sierras and also in the mountains of Col- orado and Utah; connecting forms occur at Weiser, Idaho., etc. S. cordata var. Mackenziana Hooker Fl. Bor. Am. 2 149 (1839). Mackenzie's Willow. (Mackenziana, Mackenzie's). Pods long-stipitate, the stipe being as long as the ovate or ob- long-ovate pod; leaves elliptical-oblong and shortly-acuminate, rarely wider above, acute at base; stipules very small; bark gray and smooth; twigs green; often tall trees. Ogden, Utah, both side of the Sierras and northward, apparently not common. 5. cordata var. angustata (Pursh) and. Pursh Fl. 613 (1814) as species; And. Mon. Sal. 159 (1867). Narrow Leaved Willow, (an- gustata, narrowed). Leaves linear-lanceolate, acute at base, rarely wider above, nearly entire; pods on short pedicels. This 'has the range of the type, from the mountains of Arizona and northward. 6. S. balsamifera Barratt Hook. Fl. Bor. Am. 2 149 (1839). S. cordata var. balsamifera 1. c. Balsam Willow, (balsamifera, bal- sam-bearing). Leaves oblong-ovate, sharply acute, but not acuminate, obtuse at base, minutely serrulate; stipules minute; pods lanceolate or nar- rower, the stipe twice the scale. Saskatchewan to British Columbia in the Upper Temperate Life Zone. Rare. Probably not distinct from S. cordata. Figured in Torrey Bulletin 15 121. ABBCDDEE. Leaves evidently wider above, oblanceo- late or zvider, often acute, but not conspicuously acuminate ; styles evident; leaves glaucous below except in the first; mostly shrubs about io feet high (typical lasiolepis is a tree and one form of it and one of Novae-Angliae are shrubs 2-3 feet high). ABBCDDEEF. Leaves green on both sides and not glaucous; pods short-stipitate. 7. S. Novae-Angliae And. Mon. Sal. 160 (1867). The Moun- tain Willow. (Novae-Angliae, of New England, meant for British America, an inappropriate name). Leaves elliptical-oblong, - obtuse or nearly so, 1-2 inches long, the early ones as long as the oval-oblong young catkins which do not greatly elongate and are short-peduncled; pods conical and beaked, stipe about twice the nectary; stipules small or none. From the Saskatchewan to the ; Pacific and northward in the Upper Tem- perate Life Zone of British America. S. Novae-Angliae var, pseudocordata . And. Mon. Sal. 161. (1867) The false-cordata variety. S. myrsinites var. curtifolia And., S. curti- folia (And.) Rydberg. (pseudocordata, false-cordata, referring to its relationship to S. cordata). Tip of leaves somewhat produced and acute; pods short-stipitate, long-beaked; leaves of the type but somewhat narrowed below. This is the common mountain form and can hardly be separated from S. 14 cordata except by arbitrary characters, rwhich. are leaves green on both sides, . pods short-stipitate, yo^ijjg catkins oblong-oval. Oc- casional in the middle elevations of Colorado to the East Hum- boldt Mountains* Neyada, and as '■■ far south as Marysvale, Utah, and northward'. : ,. ■ i. ,., jp, i ■-., . ,..,-- S. Novae-Angliae var. pseudomyrsinites And. Sal. B6r. Am. 129 (1858) (And.) pseudbmyrsinites, false-rnyrsinites). The false-myrtle variety. •.-'■■ -■■..' . <■',. . ■ A low shrub 1-3 feet high with divaricate branches, small mem- branous leave.s about;. 18 1 lines long, and a stipe about three times the nectary. This occurs ., in the Rocky Mountains of British America to the Saskatckewan and northward. S. Novae-Angliae var. myrtillifolia And. SaL Bor. Am. 132 (1858) (myrtillifolia, myrtle-leaved). The Myrtle-leaved variety. A very low, shrub ! widely spreading;- leaves 3-5 lineal long, .dense: pod shortly-stipitate; this grows in boggy places in 'the, mountains of British America to the Saskatchewan, etc. ' : ABBCDDEEFF. Leaves not . pubescent, oblanceo- late, acute; pods nearly s,essile;, styles merely evident;, .catkins sessile. 8. S. irrorata And; Ofvers. Vet. Akad. Forh. : 417 (18S#)." Glau- cous Willow. ! (Irrofata from the Latin in not, arid' rorare, to be- dew, the application of the name uncertain). Leaves nearly linear, bright-green above, strongly glaucous be- low; stipules minuter or none; catkins appearing before the leaves, sessile, linear, elongated, densely flowered; last year's twigs gen- erally with" a glaucous bloom, 1 shrubs 6^8 feet high. This grows In foot hills in the Middle -Temperate Life Zone from 1 the edge' of the plains in Colorado to .Silver- City, , N-ew-.M,exico, v and northward, but not yet known in Utah. 9. S. monticola Bebb. in Coulter's Man. 336 (1885). (monticola, inhabitant of the mountains), .Foothill Willow. Stipules large and persistent; pods conical-ovate, about sessile; styles elongated; catkins ..thick; leaves rather, rigid, 3-6 inches long, the earliest often obovate; shrubs 8-12 ,feet high. Apparently not common, Upper Temperate Life Zone in the mountains of Colorado arid Marysvale, Utah.' -)'' r •'••'■' isj'^nA-iiiv.jH .J ABBCDDEEFFF. .Leaves oblanceolate, acute, TS{hife- pubescent below at least .wheti, yaiwg,',becpming' rusty-colored'; pods not sessile. .. ,•,._< ,.. ■ , ■ . , 10. S.Tasiolepls Benth. PI. Hartw. 335 (1857) Silky-Scaled Wil- low, (lasjblepis frbtn the Greek meaning silky-scaled). ■ ;i Leaves in thetype from oblanceolate to oblong-oblanceola-te- and shortly-acuminate, large, the early ones' often spatulate- :■■ ABBCCD. Not-low. alpine nor sub-al'pinc shrubs. ABBCCDE. Styles! very short or none; pods' woolly. 11. S. Scouleriana Barratt. in Hook. Fl. Bor. Am.' 2 145, (1839) Scolder's" Willow. - (Scouleriana, Scolder's) S, flavescens Nutt.,' S. Niittallii Sargent. Leaves obovate to oblanceolate, normally with rounded apex and cuneate base, but' on vigorous , shoots sometimes' shortly-acuminate and base narrowed but rather 'intricate, dull and dark-green, and at length smooth above, much paler below as if /glaucous, mostly, sil- very with very minute pubescence, below, large, margin mostly 1 en- tire, catkins coming out before 1 the leases, sessile, long and slender, densely flowered; pods' lanceolate, about 2-3"lihes long, on a variable stipe from very short to longer than the' scales; styles normally none but they vary to as long as the linear stigmas; scales normally acute but often rounded, villous; twigs of the fertile plants 'lemon-yellow, of the male plants reddish ; old stems smooth and gray. This is read- ilyiseparable from other willows by the. peculiar 'leaves, or when they differ, by the sessile stigmas. Some forms approach S. Lemmoni. This is the most common willow- of 'the Middle Temperate Life Zone from the . edge oL the mountains near the plains in' Col- orado and probably New Mexico to Fish Lake, Utah*,, arid, the south- ern Sierras of. California and northward. Normally it is a slender tufted and erect shrub 15-20 feet 'high; /with wood .white to the core,, growing along ^cold streams and springs.. The most common forrti is. the var. brachystachya (Benth. PI. Hafctw. 336 (1857) 'as spe- cies) with ' sessile stigmas, short stipes and 'obtuse leaves, which "hardly deserves ', varietal* 'fa'nk!V Much Used, for, brush fences and kindling wood and poles. "' ''-'"_ ABBCCDEE. Styles longer than the, stignias.s, , ABBCCDEEF. heaves' puberulent and lighter below but wot silvery-silky nor -woolly, except wb,en yowreg; catkins large and many-flowered, the fertile oAes ,1-2 inches' long; .twigs not yellow. S. Scouleriana would be sought here when the styles are long, but the cat- kins appear before the leaves and fare sessile.; . > 16 - 12. S. Lemmorii Bebb. Bot. pal,, 2 88 (1880) Lemmon's Willow. (Lemmoni, Lemon's). '.,'-,.■, Leaves lanceolate to elliptical, acute at both ends, paler but not glaucous below, silky when young; catkins appearing, with the leaves, and with leafy and persistent bracts; the fertile ones peduncled; stipes short; pods ovate-lanceolate, variably woolly.;. A shrub 6-15 feet high growing in the Upper Temperate Life ,"2"diie from the Wasatch to the Sierras and northwestward,. , ,, , -.',' ABBCCDEBFF: Leaves at least minutely silvery- silky below, narrow .andj very acute; catkins small, appearing before the leaves and without persistent bracts. 13. glaucops And. in DC. Prod. 16 2 281 (1868). Glaucous Wil- low, '(glaucops; having the appearance of glauca), S. glauca var. vil- loma And., S. subccerulea Piper. , Leaves linear-elliptical, acute at base and rather acuminate at tip, entire, 2-3 inches long, dark green and rather dull above; stipules when present lanceolate;, catkins Iraear, about 9 lines long; pods ovate to lanceolate on a stipe about as long as the scale; twigs slender and in the type purplish and with a glaucous blpqm..' A very slender and graceful shrub, growing in spreading tufts about 8 feet high. Upper Temperate Life Zone and going down into the lower, zones some- what, along cold streams. Cpmrnqn in the mountains of Colorado and probably New Mexico through Fish Lake and Marysvale, Utah, to the Sierras of California and northward.. S. glaucops var. glabrescens And. DC. Prod. 16 2,28,1 (1868) The smoothish variety, (glabrescens, becoming glabrous), S. bella Piper. This differs from the type in the shining yellow twigs, smooth upper side of the leaves and very silvery-silky, under side, and nearly sessile pods. Middle Tempera^., Life Zone .of, the Columbia Basin and northward. ,_ ,,.',','-•' .-,,' ,,;-, :> ABBCCDD. Low' alpine or arctic or sub-alpine plants, not over a few feet high. ■ <■ •■ ABBCCDDE. Stefns not prostrate, mostly erect .in clumps. i - ABBCCDDBF. Pods glabrous; catkins thick, dense- ly flowered, linear (except in WolM) ; styles 'elongated; outer stems often divaricate, plants 3-6 feet High; related to S. cardata.' '■' ABBCCDDEFGi 'Catkins coming out before the leaves, sessile, without persistant' leafy bracts: 'li >i' 14. S. Tweedyi (Bebb. Cont. Nat. Herb. 3 $7% (1896) as Barratt- iana var. Tweedyi. Tweedy'? Willow. (Tweedyi, Tweedy's). Catkins large,. 2 inch,'es long, sessile; pods conical, large, almost sessile; leaves 2-3 inches long,' oval-oblong, acutish, cordate at; base, finely glandular-serrulate, at first floccose-pubescent, but soon smooth on both sides;' a' low shrub with widely spreading branches. Big Goose Creek, Wyoming, Big Horn Mountains. ABBCCDDEFGG.. Catkins on Jeafy peduncles, coming out with the leaves. S. Richardsonii might be sought here. , 15. S. Barclayi And. Ofvers. e. or yellqwish; cat^ins.^ linear, densely ; flowered, 1-2 inches long, on leafy peduncles cpming out with the leaves, starn- inate flowers not'known; pods broadly ovate, about 1 line long," satiny, ori a stipe about as long as the short elliptical and 4fc u ti?'fi, scalp'wjiich is sparsely short-hairy; styles filiform with short stigmaS; tjW,i^s red- dish 'and nearly black, smooth; low subalphie shrubs $ few, feet' high. Stein's mountain, eastern Oregon to the Sierras of California at^Sum- mit and northward. ' This is supposed tp have bntjone stamen is' it corresponds, so closely with S.' Sitchensis' in all otfier' respects' except tjie narrower leaves, and. is probably only a'variety of it, thoiigh Sit- chensis grows only; along the coast in ."a very different. Life -Zone. AAA. Stdmens 5 mostly (3 or more) ; scales yellow, rverys thin, mostly smooth toward the end; not darker above; all catkins coming out with the leaves and leafy-'br-Acted; 'staminate catkins linear and long (broader inS. Jasiandra).; pods smooth and stipitate, trees or tall shrubs^ with bark rough below,'' mostly growing in the Lower Temperate and Tropical Life Zones, none alpine or subalpine. AAAB. Petioles not glandular nor viscous; catkins long-peduncled, AAABC. Leaves thin; linear to linear-lancMdte and tapering from near the base to a long acumvnation; petioles 2-4 lines long. 47. & nigra Marsh. Arb. Am. 139 (i785). The Black Willow, (nigra, black): 26 Petioles smooth; leaves smooth and green on both sides but lighter below, several inches long, finely serrulate; scales deciduous, mostly entire; twigs slender; a wide_l-y branching large tree, with rough and ridged gray lower bark, and white wood, growing in moist soil, mostly near streams in the -lowlands. The common form in collections has the early twigs with linear-ohlong and shortly acuminate leaves on the twigs, which bear catkins, and thus approach- ing S. amygdaloides in the leaves. Common in the three Life Zones from British America southward. S. nigra var. Wrightii And. Mon. Sal. 22.-.{1867) ; and Vet. Ak. Forh. 15 115 (1858). Wright's Willow. (Wrightii, Wright's),. S. -oc- cidentalis Koch. _"■ -•" . ,_^_ '-: Pods long-stipitate with the stipe nearly as long- as the- pod; leaves very long and narrow, green to glaucous, below... This, is the common willow of the Tropical Life Zone of New ..Mexico and Ari- zona and southward. ...... 48. S. Humboldtiana Willd. Sp. PI. 4. 657 (1805). Humboldt's Willow. (Humboldtiana, Humboldt's). This willow has short, internodes and. linear and very long (4-5 inches); and tapering leaves green on both sides, and very slender twigs, and may occur in Southern Arizona since it: is common in Mexico. • <■ . . ..- AAABCC. Leaves narrowly elliptical to oblong-lanceolate, vari- ably, glaucous below, rather shortly acuminate; ea.ch). >v Leaves thin, .smooth on both sides, as well as the 6-9 line-long petiole,, often paler below, narrowly elliptical and shortly acuminate, mostly; catkins denser; otherwise the same as in. S. nigra from which it is hardly distinct. This is more common northward' fhough oc- curring throughout our region. " ; ' ' 50. S. laevigata Bebb. Bot. Cal. 2 83 (1880). The Smooth Willow. (laevigata, smooth, referring to the glossy upper side of the* leaves). Leaves leathery, mostly simply acute, the earliest obovate and only mucronate, dark-green and glossy above when mature (often silky when young), paler- or glaucous below, minutely serrulate; petioles' downy and short; scales denticulate; pods broadly ovate, not long-stipitate; a large shrub or small tree generally with several trunks together. This abounds. in the lowlands of western Califor- nia, but may occur along the eastern base of the Sierras southward. AAABCCC. Leaves linear-elliptical, shortly acuminate, remotely denticulate, on short, stout, woolly petioles, very glaucous below.. , 51. S. Bonplandiana HBK. Nov. Gen. & Sp. 2 24 t 101, 102 (1817). Bondpland's Willow. (Bonplandiana, Bonpland's). Leaves leathery, upper side dark and glossy, margin revplute, 3-6 inches long; catkins nearly sessile, many flowered and dense; pods conical and nearly sessile. Fair-sized trees with long and slender 27 branches, growing near water holes in the lower Temperate Life Zone from the Catalina mountains of Arizona and southward. AAABB. Petioles glandular or viscous and often with raised glands near the top; tufted and erect shrubs 10-20 feet high; catkins thick; grow- ing in the Middle Temperate Life Zone along streams. 52. S. lucida Muhl. Neue Schrift. Ges. Nat. Fr. Berlin 4 239 t 6 f 7 (1803). The Glossy Willow, (lucida, shining). Leaves from ovate to lanceolate, and acuminate, rather rounded at base, sharply serrulate, smooth, green and glossy; on both sides or sparingly hairy- when young; petioles with conspicuous glands at the top, stout, 3-6 lines long; catkins short-peduncled. This grows along the eastern base of the Rocky ' Mountains of British America and eastward.' 53. S. lasiandra Benth. PI. Hartw. 335 (1857). Waxy Willow, (lasiandra, with hairy stamens). Leaves linear-lanceolate to oblong lanceolate, mostly shortly acute at base and acuminate at tip, very closely and, finely serru- late, rather leathery, very bright green, as . if waxy, at least above, 3-6 inches long, smooth, growing in swabs at the ends of the twigs, the petioles and twigs appearing waxy or glutinous and variably short-woolly; stipules semi-lunar, glandular-dentate and mostly large; catkins very thick and dense, 1-3 inches long, linear-oblong to linear, very yellow, long-peduncled and leaves of peduncle 1 often as long as the catkins and mostly oblong-linear and shortly acuminate; scales dentate, large, rather smooth above; styles short; pods ovate with a short-triangular beak, 2 lines long, about twice the filiform and smooth stipes; large shrubs with long and strict branches and smooth gray bark except at the very base. The typical form has narrow leaves, glaucous below; small stipules; scales evidently dentate; first year's twigs yellow, and second year reddish. This grows in the Middle Temperate Life Zone and frequents both sides of »the Sierras from California to Oregon. S. lasiandra var. lancifolia (And.) Bebb., And., Mpn. Sal. 34. f 23 (1867), as species; Bebb. Bot. Cal. 2 84 (1880). The Lance-leaved variety, (lancifolia, lance-leaved). Leaves tapering' from near the base to a long and often falcate acumination, green on both sides; Scales' of fertile catkins often linear, those of the sterile catkins dentate and wider, but vari- able. From the Sierras of California to Mt. Ibapah, western Utah and northward. S. lasiandra var. Fendleriana (And.) Bebb, And. Sal., Bor. Am. 115 (1858) as species; Bebb. Bot. Cal. '2 84 (1880). Fendler's Variety. (Fendleriana, Fendler's), S. lasiandra var. caudata (Nutt.) Sudworth. Leaves oblong-lanceolate with a short acumination, green on both sides. It reaches 20 feet high, but' usually is 10-15 feet high,' with a trunk often 4 inches in diameter, always, growing in dense tufts with flexuous gray stems with rather thick; and long lemon-yellow season's twigs. It is the most beautiful of the willows of the Great Plateau, and is the common form from the Sierras of California eastward to New Mexico and northward in the mountain canyons. 28 POPULUS L Syst., Gen. 307, Sp. PI. 1034. POPLAR, ASPEN, COTTONWOOD. Catkins coming out before the leaves, axillary and sessile or nearly so, the female elongating. and slender; pendulous; bracts deciduous, lacerate, "broad ;'stam'ehs many on, the face of a broad and truprate di^k,; ovary with a cup-shaped .disk belpw ; pods ob- long-ovate to orbicular 1^-5 lines "long; buds scaly and mostly resinous;.. stipules deciduous ;. leaves. ibroad except in same^£orms of P. angustifolia. Trees with soft, brittle, and white wood, r bifc- ter -bark ; quick growers, thriving in moist places only, and mostly at low eleyations". A genus of : about 25 species. The green bark a hitter tonic, good for fevers,' etc. Key to Species. ,, A, B.ttds glmHnpuA and large or longi bracts smooth or nearly so; mafe catkins red. ' . ■ , , , - ; ( , AB-., Serraturesi€/ng and, stnallj many. ABC. Petioles not. evidently flattened. ABCD. Pods and. ovaries smooth, ...... Leaves linear-lanceolate to ovate,, base cuneate flti^, tip acuminate; twigs slender.,- . . ;v ; u ..<.<■. --..,.. ,i, t P.. angystif/Qlia. '■' Leaves ovate, mostly with a cordate base; iwigs • thick; upper stems and branches whiter • • ■■<■■'.<•• t.2. P fyilsamifcra., AJ}CDD. Ovaries^ evidently hapryL twigs thick.; uppe'f- stems and branches' white; leaves', gtaucous below. S-' P. trichocarpa. ''"'-'" ABCC. Petioles evidently , flattened; leaves mostly,, as'w.i.de.as long or. wider.. .' '-.'" ''."" l \ Leaves mostly rhomboidaf with a tru'nca(e ,to cuneate bti'se and acuminate tip; cullivaie'd tree's!' 4. P. nigra. Leaves from nearly orbicular to renifdrm/Vaie- truncate to cordate, fijft shprt and sharp. '-■'" , 5. P: deltoides.' '• ' ABfi. Serratures large and'fezv, mostly 7-lo.'on, r a/ side'.' 6. ' P. -Fremonti. AA.. Buds nOjl glutinoMs, small; bracts' white-hairy. ' Leaves' smooth, finely if at all serrulate, nearly entire. 7. P. tretnuloidei. Leaves silvery-whiie-hairy below, very coarsely, dentate. ' """ '■'■■ 8. P.'alba. 29 4>, Buds, larger, ar long and glutinous; bracts, snioftA 6-r. nearly so; mole catkins red; roots inclined to produce suckers; trees in the natural* isfettg having innumerable branches -a few feet "above the ground (usually where the first large branches start) forming a dense mass. AS. ] Serratures many, fine and nearly always small. ABC. P.etiples rounded or flattened only at very tip.;, styles S-.3; pads nearly sessile; leagues longer than wide, waxy above; plants of cap[ climates, of 1 the Middle Temperate or Upper Temperate Life Zones,, found only in the. ^mountains below hat. 42 deg., and native, only in high valleys and mountains above it; trees balloon-shap-ed in outline. ■ ■■•■ , ■ ABCD. Pods and.ovaries smooth, the former short-pediceled. 1. P. angustifolia James Long's Exp. 1 497 (1823). The Long r leaved Cottonwood. Black Cottonwood, (augiistifolia, narrow- leaved). Leaves normally narrowly lanceolate and acuminate from a cif- ne&te base 'and closely serrulate, 2-4 inches long and on a short pet- iole about 6 lines long, and yellowish-green on both sides, willow- like, but often, especially at low elevations, the leaves vary oh the same tr'ee to rhorhboidal ovate with a truncate base, and the petioles vary to 2 inches long, and the under side of the leaves is often a lit- tle glaucous, the gerratures,. vary from, evident crenulations 1-2 lines high to .very minute Sn'd ijhore' numerous, ' often absent at tip and base. The plant can usually be separated 1 from its • cbrfgeners by the slender twigs, narrow, nearly linear an'd acuminate buds, great variability of leaves" on the same ' tree, and by the ' larger branches being little glaucous, arid ' 'as ' the tree gets old, by the large branches dying one by one 1 giving it an unsightly' appearance. When the leaves are triangular-ovate' on long' petioles' and - without ■ serratures at each end then it is" P: acuminata Rydberg, a very inappropriate name, but only isolated trees are like this, while there are all sorts of inter- grades.. The pods are oval to ovate, 2 lines long, barely acute, cross- section found 'with no ridges nor angles When fresh, pedicels 1 line long and slender, torus 1 line wide; rac'emes 3 inches long; bark oh the upper limbs brownish-green, and without bloom, the cambium layer, turns u black soon, after being cut across; bark on the main trunk and "larger branches often 2 inches thick, soft, cracked intp isharp ridges. which are regular, and long and : composed of many thin lamination's which do not flake off; wood white to the, core, of, soft fibers surrounding the innumerable pores, annual rings broad; last season's- twigs slender, chestnut-colored, becoming lighter in spring . and shining, and at length gray; a rapid grower, maturing in about 25 years and becoming scraggly after that. A tree generally about SO feet high, with few straight branches coming put at acute angles and ■ again branched; much planted , for ornament, but soon becoming un- sightly and wormy. It is probably the worst shade; tree- .planted, the Lombardy comifjg next. Very.commpn from the Plains to the Sier- ras and northward, .local only in the high mountains of. Arizona and ?, New Mexico along streams, but coming down into, the, valleys, of cen- tral Utafh and northward, though also growing up to 8,000 feet alt. in the mountains. It is much used for fuel, posts and pol.es; bjit soon 30 rots, seldom used for lumber as the trees rarely reach 2 feet in di- ameter. ' 2. P. balsamifera L 1034. Balm of Gilead. (balsamifera, balsam- bearing). Leaves ovate from a truncate to cordate base, dark green above and more or less glaucous below, slender-petioled; twigs stout, the last season's mostly chestnut-colored, with very large, acute and very resinous buds; pods 3 lines long, deeply 2-3-grooved. A very large and magnificent tree, often 100 feet high, with great ringed branches, spreading at an acute angle which are white and glaucous almost throughout, and much branched but not into the many Slender twigs of the above, rather long-lived, and trunk sometimes 6 feet in diam- eter. The variety candicans (Ait.) Gray, Aiton Hort. Kew. 3 406 (1789) as species; Gray Man. Ed: 2 419 (1856) has cordate leaves, pu- bescent petioles and silvery-white under side of leaves, but hardly de- serves varietal rank. This tree abounds from Newfoundland to New Jersey, and westward through northern Colorado to Idaho, and north- westward and northward to Alaska. It replaces the cottonwood in the cold valleys!- It is planted for shade in Utah and western Nevada;, though not native there, and is everywhere so used throughout Mon- tana and Idaho. It is much used for fuel, poles, fences, etc. The wood is about -the same as the above. , , ABCDD. Pods hairy when young; styles 3. 3. P. trichocarpa Torr, & Gray in Hooker's Icones 9 t 878 (1850) Cottonwood, (trichocarpa, hairy-ppd). Leaves from ovate with a truncate to cordate base to broadly lanceolate, acuminate, much lighter below, . inclined to yellowish on the veins below; otherwise as in P. balsamifera of which it, is hardly more than a variety. Common in the Sierras and adjacent ranges of western Nevada and northward alpng streams and much planted for shade in Utah, etc. .; ABCC. Petioles evidently flattened'; leaves mostly as 'wide as long or wider;, pods on short pedicels; plants of the Middle' to Lower Temperate Life Zones. 4. P. nigra L. 1034. Lombardy Poplar. Black Poplar, (nigra, black). Plants introduced from Europe, the staminate ones narrow and spire-like, the pistillate ones with widely-spreading branches for the most part. Leaves mostly rhomboidal with a truncate to cuneate base and acuminate tip-; pods oblong, obtuse; twigs round. The staminate form called variety dilatata is much planted for ornament throughout the Great Basin, because it is so conspicuous. It forms a good wind- break, but soon dies, limb by limb, and becomes unsightly and is much prone to the production 'of suckers from the roots. The typical form is cultivated at Salt Lake City. 5. P. deltoides Marsh. Arb. Am. 106 (1785). Cottonwood, (del- toides, deltoid). P. monilifera Aiton and P. angulata Aiton. Trees in outline nearly hemispherical, often 100 feet high and 6 feet ; thick at base, with nearly horizontal and long lower branches, all branches light-green above and the larger ones with rough bark 31 below as well as on the main trunk^Jwigs inclined to be angled, slender, often drooping; leaves broadly deltoid, oblate or almost reniform, rarely at all cordate, but with truncate to broadly cuneate base, abraptly acuminate, often very large, rather light-green, on a petiole about as long as the blade; bark cracked much as in P. an- gustifolia, but the ridges flat on the tdp and warty; pods ovate, acute, 4-5 -lines long, longer than the pedicels; scales less fimbriate than in the next. This is the finest tree of the genus, makes an admirable shade tree, is long-lived, and does not die limb by limb;, it is a very rapid grower. Cultivated in Salt Lake City, etc.- Native along streams on the plains of Wyoming to Texas and sparingly through Arizona to the' southern Sierras. Rare west of the Plains. ABB. oerratures large and few, mostly 7 on a side, forming scallops. 6. P. Fremonti Watson Proc. Am. Acad. 10 348 (1875). Fremont's Cottonwood. (Fremonti, Fremont's). •' . Trees doubtfully distinct from and with the habit of P. deltoides, and with the light-green branches and smooth pods, long petioles and wide leaves of that species; it differs from it in the few and large teeth, smaller mostly reniform or cordate -leaves, broad torus or disk often 3-4 lines wide. The last season's twigs are shining, not angled, yellowish or chestnut-tinged; the smaller branches are often 6 feet .long and drooping; pods ovate, 4-5 lines long, round when fresh, on pedicels 2-3 lines long in the type, in long recemes; scales fimbri- ate with long threads; the serratures on the upper leaves are often more numerous and even on the lower ones in the type, but usual- ly are few and large, in the type they are more numerous and often 2 lines high and sharp and narrow; edges of the leaves with cartil- aginous and sharp and cilate margins; buds ovate-lanceolate, acute, large. Very common in the valleys of Central California, rare in the interior to Colorado on the plains. P. Fremonti var. Wislizeni Watson Torrey Bull. 9 79 (1882). (Wislizeni, Wislizenus's). Pedicels 6-8 lines long; leaves with few and broad scallops. This abounds throughout the Lower Temperate and Tropical Life Zones from middle Colorado on the Plains through northern Utah to the Sierras in southern Oregon and southward to Mexico. It is every- where cultivated for shade, is a rapid grower, a magnificent tree and long-lived; it grows along streams, at springs and in moist places only; like the above it is much used for fuel, poles, posts, arbors, etc. Much complaint is made against the cottonwoods because of the cotton from the female trees, but this can be obviated by watching the trees in the spring and selecting cuttings only from those that produce red pussies or catkins, which are male and pro- duce no cotton. AA. Buds not glutinous, small; bracts white-hairy. 7. P. tremuloides Michaux Fl. Bor. Am. 2 243 (1803). Aspen. Poplar. Quaking Asp. (tremuloides, like tremula). Erect trees, with main -trunk not branching and strong terminal buds and short and small lateral branches which are nearly horizontal and soon dying below and dropping off; trunk mostly white and warty 31 to the base, occasionally roughened; at base and with cracked bark; outline of tree narrow; leaves, nearly round, 2-6 inches wide, green, smooth, leathery like the. rest, , of the species, on a, much flattened petiole, constantly -in jnqtion; buds black; tips of .twigs in spring dark chestnut-brown; catkjns dark and fuzzy; pods 14-2 , lines long; styles 2; scales deeply cleft. The straight stems are ; rmlqh used for poles, lagging, fences and fuel. It abounds in the mountains, in all situations in the Upper Temperate Life Zone from Mexico north- ward, and in Idaho and Montana in the cold valley^ forming large patches/ and even forests, and is the foster mother of the ever- greens -filling all open spaces and shading the young conifers till they shoot up above it. It is a short-lived tree, rarely reaching 2 feet in diameter, and usually about 6 inches thick, forming dense thickets of •white poles. 8. P. alba ~L. 1034.: Silver-leaved Poplar, (alba., white) . Cultivated trees with rounded outline and. widely-spreading branches, which are white'and repeatedly forked, much after the style iof P. trichocarpa, but more branched; leaves silvery-haired below, dark-green above,! and somewhat hairy, coarsely and remotely den- tate or ^almost lob'ed, ovate, rather large; petioles not flattened, woolly bracts shortly toothed; buds ovafe. ,, A lorig-lived tree with large trunk and very vigorous growth,; spreading much by suckers from the; roots. Salt- Lake City, etc. V 4 : m-i^ mm. • V ♦ : s£ tim ^ c ! _$T : :H :>*-