Chromatographic characteristics and phylogenetic relationships of "Artemisia", section "Tridentatae"

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a

‘USDA Forest Service

: Research caper INT-1417 33:

1973

CHROMATOGRAPHIC
CHARACTERISTICS
AND PHYLOGENETIC
RELATIONSHIPS OF
ARTEMISIA,
SECTION TRIDENTATAE |

David L. Hanks,
E. Durant McArthur, Richard Stevens,
and A. Perry Plummer

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INTERMOUNTAIN FOREST & RANGE EXPERIMENT STATION
Ogden, Utah 84401

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USDA Forest Service
Research Paper INT-141
September 1973

CHROMATOGRAPHIC
CHARACTERISTICS
AND PHYLOGENETIC
RELATIONSHIPS OF
ARTEMISIA, SECTION TRIDENTATAE

David L. Hanks, E. Durant McArthur,
Richard Stevens, and A. Perry Plummer

Federal aid in wildlife restoration funds
was provided through Project W-82-R

INTERMOUNTAIN FOREST AND RANGE EXPERIMENT STATION
Forest Service
U.S. Department of Agriculture
Ogden, Utah 84401
Robert W. Harris, Director

THE AUTHORS

DAVID L. HANKS was a Plant Physiologist in 1969 and 1972 for the Intermountain
Forest and Range Experiment Station in Ephraim, Utah. He received his
B.S. degree in Botany (1962) and M.S. degree in Chemistry (1963) from
Brigham Young University. He obtained his Ph.D. in Plant Physiology (1966)
from the University of Michigan. Between 1966 and 1969, he taught mycology
and plant physiology at Brigham Young University. He is presently Assistant
Professor of Microbiology, Division of Science, at Northeast Missouri State
University, Kirksville, Missouri.

E. DURANT McARTHUR is a Research Geneticist for the Intermountain Station at
Ephraim. His degrees are from the University of Utah: B.S. in Genetics and
Cytology (1965), M.S. in Molecular and Genetic Biology (1967), and Ph.D. in
Biology (1970). He was a Postdoctoral Research Fellow of Agricultural
Botany at the University of Leeds, United Kingdom, in 1970-1971. He joined
the Station in 1972.

RICHARD STEVENS is a Game Biologist for the Utah Division of Wildlife Re-
sources. He received his B.S. degree in Range Management (1965) from
Brigham Young University, and his M.S. degree in Range Management (1968)
from the University of Arizona. From 1968 to 1969 he was a Range Conser-
vationist with the USDA Forest Service. He has been in his present position
since 1969.

A. PERRY PLUMMER is a Range Scientist for the Intermountain Station at
Ephraim. He has worked in range research for the Station since 1936. He
received his B.S. degree (1935) and his M.S. degree (1939) in Botany from
the University of Utah. His research has been principally concerned with the
restoration of western ranges.

ACKNOWLEDGMENT

We thank R. Drobnick and R. B. Ferguson, and Drs. R. G. Krebill, E. Schlatterer,
H. C. Stutz, and R. K. Vickery, Jr., for critically reviewing an earlier draft of
this paper. This work was facilitated by use of study plots on land belonging to
the Utah Division of Wildlife Resources and the Snow Field Station of the Utah
Agricultural Experiment Station and of Snow College. Some plant material was
collected and/or identified by A. C. Blauer, B. C. Giunta, K. R. Jorgensen,
A. McLean, and G. A. Van Epps.

CONTENTS

Page
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EXPERIMENTAL PROCEDURES .....+ 22-22 eee a
RESUS gt catieks: a) 6:6 8s tee ie Bw oe Fe, 5
DISCUSSION 5.6. Scere. @ w wie ee Bose Fa Ee eS 13
LITERATURE Cll BD) & ace a s256 @ Slew So es erin 18 23

The use of trade, firm, or corporation names in this
publication is for the information and convenience of the
reader. Such usedoes not constitute an official endorse-
ment or approval by the US Department of Agriculture
of any product or service to the exclusion of others
which may be suitable.

ABSTRACT

On the basis of a chromatographic analysis, Artemisia
tridentata is divided into seven subgroups: three of subspecies
vaseyana, three of subspecies tridentata, and one ‘of sub-
species wyomingensis. The three subgroups included in A.
tridentata subsp. tridentata show low utilization by game and
livestock; the four subgroups included in subspecies vaseyana
and wyomingensis show high utilization, especially on winter
ranges. Although each subgroup occupies a distinctive ecolog-
ical habitat, few consistent morphological differences are
manifested, particularly among the subgroups of subspecies
vaseyana and subspecies tridentata.

Chromatographic comparison of the species in the
section Tridentatae suggests that subgroup IIc of A. tridentata
subsp. tridentata may have been the ancestral form to develop
from A. biglovii. In turn, this form probably gave rise to the
remaining subgroups of A. tridentata and most other species
in this section.

INTRODUCTION

Sagebrush species of the genus Artemista section Tridentatae! occur discontinuous ly
as dominants or partial dominants on over one-third of that portion of the contiguous
United States west of 102° W. longitude (Beetle 1960). Some of these taxa also occur
in adjacent areas to the east and in Canada and Mexico. Sagebrush is an important con-
stituent on much of the West's rangeland. It serves as forage for wildlife and live-
stock and as cover for birds and small animals. Moreover, sagebrush has watershed and
recreation values.

Section Trtdentatae is noted for both intraspecific and interspecific morphological
variation (Hall and Clements 1923; Ward 1953; Beetle 1960, 1970). Hybridization and,
to a lesser extent, introgression contribute to the morphological plasticity of the
Tridentatae. These processes have been important in the reticulate evolutionary past
of the section. Despite the variability of the group, Beetle's (Beetle 1960; Beetle and
Young 1965) taxonomic treatment approaches practical workability.

Cytological studies were initiated by Diettert (1938). Diettert's and subsequent
studies show the Tridentatae to be a polyploid series based on the chromosome number of
x = 9 (Clausen and others 1940; Ward 1953; Taylor and others 1964; Winward 1970).
Diploid (” = 9), tetraploid (m = 18), hexaploid (nm = 27), and octoploid (” = 36) popula-
tions have been discovered. Although chromosome numbers for over 50 populations have
been determined, no detailed meiotic or karyotypic studies have been performed. The
chromosome numbers now available do not clarify the phylogenetic relationships within
the Tridentatae over most of its range. However, in areas of the Northwest, diploid
and tetraploid populations appear to be clearly separated by elevation (Ward 1953;
Taylor and others 1964).

lIn this paper, section Tridentatae Rydb. is recognized over the analogous section
Sertphtdtum Besser. Taxonomic treatment of species follows Beetle (1960) and Beetle
and Young (1965).

Figure 1.--Differen-
ttal graztng of two
A. tridentata subsp.
vaseyana bushes tn
the Seeley Creek
Dratnage, Sanpete
County, Utah.

Chemotaxonomic methods have recently been used to study taxa within the Trtdenta-
tae. Chromatographic investigations by Holbo and Mozingo (1965), Young (1965), Winward
and Tisdale (1969), Hanks and others (1971), and Brunner (1972) give support to the
taxonomic treatment of species and subspecies by Hall and Clements (1923) and Beetle
(Beetle 1960; Beetle and Young 1965). Identification and distribution of leaf phenols,
sesquiterpene lactones, and alkanes are proving to be of value in delimitating Artemtsta
species (Shafizadeh and Melnikoff 1970; Shafizadeh and others 1971; Bachelor and
others 1972).

Our special interest in sagebrush arose primarily from questions as to why game
and livestock exhibited marked preferences for certain big sagebrush populations
(Brunner 1972) or for certain individuals in a population (fig. 1). In earlier
chromatographic work (Hanks and others 1971; Hanks and Jorgensen 1973), we reported
evidence for and means of detecting some of these differences in subspecies of big
sagebrush (Artemtsta tridentata subsp. tridentata and A. tridentata subsp. vaseyana).
In the course of this research, chromatographic analyses were done on other species in
the Tridentatae as well. This paper stresses some considerable differences discovered
among these species through chromatographic studies in 1969 and 1972, and outlines
phylogenetic relationships among these species as suggested by chromatographic patterns.
Other chromatographic analyses have been performed in the Tridentatae; however, this
study is much broader in scope and builds on earlier work.

The large amount of genetic variation in natural populations of Artemisia provides
wide opportunity for the development of improved races through artificial selection
and breeding. Chromatography offers a rapid means of verifying the existence and
extent of hybridization and also a technique for identifying types that would satisfy
specific purposes.

EXPERIMENTAL
PROCEDURES

Chromatographic analyses of more than 350 plant specimens are included in this
study. The plants chromatographed came from widely occurring populations in Utah,
Idaho, Nevada, Wyoming, Colorado, Arizona, Oregon, and British Columbia, and include
most species of the section Tridentatae. Attempts were made to collect from a wide
variety of sites so that collections would be fairly representative of the distribution
of species and subspecies. Although the majority of collections were taken from sites
within the Great Basin, many were obtained from populations outside this geographical
area.

Artemtsta populations were sampled by collecting foliage from mature representative
individual bushes. Naturally occurring and transplanted bushes were sampled, Trans-
planting apparently did not affect the chromatographic patterns. Sampled foliage con-
sisted of persistent, overwintering leaves from nonflowering stalks. Leaves on Arte-
mista flowering stalks have been reported to give variable results in chromatographic
studies (Winward and Tisdale 1969; Brunner 1972). Early results indicated little
seasonal variation in chromatographic patterns from persistent leaves; consequently,
foliage was collected during all seasons of the year. Foliage was placed in open brown
paper bags and dried at room temperature.

A modification of the chromatographic methods developed by Alston and Turner (1962)
was employed. A mortar and pestle were used to pulverize 0.5 g. of dried leaves.
Samples were placed in 30 ml. bottles into which 7.0 ml. absolute methanol had been
introduced. Extraction of phenolic substances was carried out at room temperature for
24 hours. The extract then was decanted and concentrated by evaporation to 2.0 ml.

Twenty-five ul of this extract were added to duplicate 9-inch squares of Whatman No. 3
MM chromatographic grade filter paper. The solvent system for the first dimension

was n-butanol:acetone:water (4:1:3) and for the second dimension, acetic acid:water
(15:85). Chromatograms were viewed under longwave ultraviolet light before and after
exposure to ammonia fumes in order to note the appearance and color changes of result-
ing spots. Each spot was given an arbitrary number for identification purposes and the
Re value computed for both dimensions of the finished chromatogram.

_ Distance of spot from starting point

f Distance of solvent front from starting point
The Re value of a given spot is then expressed as:
Re = Rp(first dimension) /R,(second dimension).

Thin-layer plates coated with silica gel G were photographed to illustrate the
difference among groups of big sagebrush. Each plate was divided into three 6- by
20-cm. sections and the base of each section was streaked with approximately 200 ul of
extract. Chromatograms were developed in a single direction using n-butanol:acetone:
water (4:1:1) as the solvent system. Following. development, the plates were exposed to
ammonia fumes, allowed to dry, and photographed under ultraviolet light (Kodachrome II
film, ASA 25, and a 2B filter).

Identification of the constituents of the methanol extracts is beyond the scope of
this paper. Shafizadeh and Melnikoff (1970) report that phenolic extractives of
Artemtsta trtdentata subsp. vaseyana leaves are mainly coumarins with various side
chain substituents.

RESULTS

On the basis of chromatographic variations among collections of big sagebrush, the
sources studied are divided into two major groups and seven subgroups (figs. 2-8 and
table 1). Several of the chromatographic spots exhibited significant variations in
size and intensity of color; so both qualitative and quantitative (table 2) variations
were taken into consideration when the chromatograms were organized into groups.
Characterization of chromatographic spots of big sagebrush by R, values and colors
(figs. 2-8 and table 2) is nearly identical with data presented in an earlier paper
(Hanks and others 1971). The few changes represent judgments reached after further
investigation, except for the R, value of spot 4, which was misprinted in Hanks and
others (1971). The missing numbers in the sequence (table 2) represent spots that
appeared only occasionally in the chromatograms and, in most instances, provided no
useful basis for the organization of the collections into groups. However, some of
these might be indicative of past hybridization between big sagebrush and other
sagebrush species.

Variation within species or subspecies was also observed among other Tridentatae
species. Representative chromatograms of each (i.e., A. arbuscula subsp. arbuscula,
A. arbuscula subsp. thermopolae, A. biglovit, A. cana subsp. bolandert, A. cana subsp.
cana, A. cana subsp. visetdula, A. longiloba, A. nova, A. pygmaea, A. rigida, A. roth-
rockit, A. trtparttta subsp. triparttta) are illustrated in figures 9-25. Distribu-
tion of chromatographic spots among each is included in table 1. Re values and color
variations of the individual spots are given in table 2.

Figures 2-25.--Representative two-dimenstonal chromatograns of methanol-soluble
extraets from the leaves of the subgroups of A. tridentata (figs. 2-8) and other
spectes of sectton Tridentatae (figs. 9-25). For spot coloration and R, values,
see table 2. f

(subgroup |

a
eS

ca) §
"3

(subgroup la)

A arbuscula A arbuscula
arbuscula (a) arbuscula (b

4

A. arbuscula
ther ae
a

3X

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Table eet values and color of the chromatographic spots in Artemisia species

Spot no.

nPwWe

Ultraviolet

Blue
Blue-green
Violet
Yellow or
yellowish-brown
Yellow or
yellowish-brown
Violet
Dark blue
Bright, iridescent
blue

Blue
Pink
Blue
(Violet in IIc)
Dark blue

Blue

Blue-green

Blue

Blue
Pinkish-white
Blue

Brownish- gold
Brownish-violet
Brownish-violet

Violet

Violet
Blue

Color
NH, + ultraviolet

Yellow-green
Blue-green
Violet-brown
Yellow or
yellowish-brown
Yellow or
yellowish-brown
Violet
Dark blue
Bright, iridescent
blue
Blue
Yellow-green
Blue-violet
Yellow-pink
Gray-blue
(Violet in IIc)
Dark blue
Orange
Orange
Blue-green
Blue-green
Blue
Yellow-green
Pink
Blue
Brownish-gold
Yellow-green
Brownish-violet
Brownish-violet
Blue-green
Blue-violet
Tan
Violet
Blue-green

NH, + daylight

Gray

Yellow

Yellow-brown

Yellow

Gray

Table 3.--Color of extract from each of seven subgroups of
A. tridentata under ultraviolet light

Color of extract under

Sub group : ultraviolet light
vaseyana Ia Bluish-white to light blue
vaseyana Ib Bluish-green to bluish-violet
vaseyana Ic Creamy-white to bluish-white
wyomingensts Id Brownish-violet to greenish-violet
tridentata Ila Bluish-violet to greenish-violet
tridentata IIb Greenish-violet

tridentata IIc Violet to reddish-violet

Comparisons of single-dimension, thin-layer chromatograms of the seven subgroups
of A. tridentata are shown in figures 26-32.

Another rapid, but less accurate, method of separating collections of big sage-
brush into the previously described groups was detected during the course of the study.
Viewed directly under ultraviolet light, methanol extracts fluoresce in distinctive
colors based on the relative brilliance of the phenolic substances already described
in the chromatographic analysis (table 3). Young (1965), Winward (1970), and hauabavens
(1972) have used thin-layer chromatography to distinguish Artemtsta taxa.

The chromatographic spots that exert the greatest influence on composite colora-
tion are 9, 5, and 6. Where spot 9 is large and brilliantly iridescent and 5 and 6
are only lightly colored (vaseyana Ia and vaseyana Ic), the extract is a brilliant
creamy-white to bluish-white. However, when spots 5 and 6 are brilliantly colored
(vaseyana Ib and wyomtngensts Id), much of the brilliance of 9 is masked. In such
cases, the composite color reflects the yellow of these spots and produces varying
shades of brownish- and greenish-violet. In group II, where the intensity of spot 9
is much reduced, a corresponding reduction in the blue coloration of the composite
mixture occurs that results in a strong violet background. The usefulness of this
technique lies in the fact that the group to which big sagebrush belongs can be
determined a few hours after collection. Since this determination is only qualitative,
extraction of the leaves can begin at the time of collection, thus eliminating the
drying time necessary for a more quantitative analysis. Winward and Tisdale (1969)
outline a similar technique.

The same method also appears to be effective with seed. Methanol or water extract
of big sagebrush seed from each subgroup fluoresces in colors similar to but less
intense than those from corresponding foliar material. Consequently, it is a rela-
tively simple procedure to determine the subspecies from which seed was harvested
(Taylor and others 1964; Hanks and Jorgensen 1973).

Figures 26-32.--Color photographs of representative thin-layer chromatograms of

the methanol-soluble extracts from the leaves of the seven subgroups of
A. tridentata. The origin ts on the left. The bright red band near the !
solvent front (right) is chlorophyll A. Fig. 26, subsp. vaseyana subgroup
la; fig. 27, subsp. vaseyana subgroup Ib; fig. 28, subsp. vaseyana subgroup i
Ie; fig. 29, subsp. wyomingensis subgroup Id; fig. 30, subsp. tridentata
subgroup IIa; fig. 31, subsp. tridentata subgroup IIb; fig. 32, subsp.
tridentata subgroup IIc.

10 |

26

igure

=

la

27

Figure

ib

28

Figure

Ic

29

Figure

Id

Figure 30

Ila

31
lib

Figure

32
lic

Figure

Beal

Sy

DISCUSSION

Evidence for the great plasticity of the Tridentatae complex and particularly of
big sagebrush, suggested by Hall and Clements (1923) and further demonstrated by the
cytogeographic studies of Ward (1953), is substantiated by the large number of
chromatographic variants resulting from this study.

Greatest chromatographic variation was observed among collections of big sagebrush;
at least seven rather distinct patterns were identified. Considerable additional
variation was found among individual chromatograms of collections of this species, but
these could not be associated with meaningful patterns. Similar multiple patterns
(table 1) and incidental variation were found among collections of other species and sub-
species, but none of these approached the apparent chemical diversity of A. trtdentata.

The most common departure from regular chromatographic patterns seemingly resulted
from interbreeding between Tridentatae species or subspecies. Chromatograms of progeny
from naturally occurring hybrids could be identified by the appearance of spots specific
for one parent species in the otherwise normal chromatogram of another species. The most
common example of this phenomenon was the occurrence of traces of spot 19 from A. nova
or A. cana subsp. vtsetdula in approximately one-fourth of the A. tridentata subsp.
tridentata and vaseyana collections. In support of this contention, Beetle (1960)
reported considerable evidence of A. nova in the morphological characteristics of big
sagebrush populations on the Shivwitts Indian Reservation, Washington County, Utah.
Chromatograms of collections from this vicinity, which were included in this study,
contained a rather prominent spot 19, which supports Beetle's observation as to close
relationship of this form to A. mova. Further evidence of past hybridization was the
appearance of spot 20, specific for A. trtpartita subsp. trtpartita in approximately
20 percent of the collections of subgroup la of A. tridentata vaseyana (fig. 33). This
spot was observed in widely scattered populations of subgroup vaseyana Ia from south-
western Idaho to southern Utah. Usually, the introgression shown by chemical patterns

1S)

Figures 33-34.--Repre-
sentative two-dimen-
stonal chromatograms
{ 20) 9 of methanol-soluble
Cy : extracts from the
leaves of putative
hybrids A. tripartita
X A. tridentata subsp.
vaseyana subgroup Ia
(fig. 33) and A. tri-
ee dentata subsp. vaseyana
subgroup Ib X A. tri-
dentata subsp. tri-
dentata subgroup IIb
(fig. 34).

(A. tripartita (Ib xI1b)
x la) i

could not be associated with morphological characteristics. This type of introgression
has wide distribution within the sagebrush populations. Collections taken from ecotones
between populations of different species, subspecies, or ecotypes frequently express
both morphological and chromatographic evidence of interbreeding.

Chromatographic evidence for hybridization between the following taxa was observed:
A. trtdentata subsp. vaseyana X A. trtdentata subsp. tridentata; A. trtdentata subsp.
vaseyana X A. arbuscula subsp. arbuscula; A. tridentata subsp. vaseyana X A. nova,
A. tridentata subsp. vaseyana X A. tritpartita subsp. trtpartita; A. trtdentata subsp.
vaseyana X A. cana subsp. vtsetdula; A. trtdentata subsp. tridentata X A. tripartita
subsp. trtparttta; A. cana subsp. visctdula X A. trtparttta subsp. trtpartita. Examples
are illustrated in figures 33 and 34. We are confident that many others will come to
light as this technique is more widely applied.

Ecologtcal dtstributton.--The following observations have been made regarding the
ecological distribution of the chromatographic groups of big sagebrush, primarily
within the Great Basin. Collections of Group I (Artemtsta trtdentata subsp. vaseyana
and subsp. wyomingensts) have come mostly from mountain habitats extending from the upper
elevational limits of the big sagebrush zone to, and slightly beyond, the base of
the foothills. Specimens of vaseyana Ic, which were all collected from the upper eleva-
tions of the big sagebrush zone, appear to be widely distributed, as is evidenced by
collections of this subgroup (vaseyana Ic) from Utah, Idaho, Nevada, Wyoming, and
Colorado. Vaseyana Ic may include A. tridentata subsp. vaseyana f. sptetformts
(Beetle 1960; Winward 1970). The distribution of vaseyana Ia extends downward from
the vaseyana Ic zone to the lower foothills, overlapping considerably with vaseyana Ic
in the upper elevations and vaseyana Ib in the foothills. Subgroup vaseyana Ib
predominates in the lower foothill pinyon-juniper zone and extends into peripheral
lowland areas where it overlaps with trtdentata IIb. It is interesting that Winward
(1970) recognized an analogous or perhaps identical taxon to our vaseyana Ib in his
taxonomic and ecological study of Idaho big sagebrush. He tentatively referred to this
taxon as A. tridentata subsp. vaseyana f. xericensts. However, that name has not been
validly published (Winward 1970).

Subgroup wyomingensts Id (which occurs in Wyoming, Montana, southern Idaho, north-
ern Nevada, and northern Colorado) overlaps vaseyana Ib, the lower end of vaseyana Ia,
and to a greater extent, the upper end of tridentata IIb. Beetle and Young (1965)
maintain that A. tridentata subsp. wyomtngensts is intermediate in ecology, morphology,
and distribution between A. trtdentata subsp. vaseyana and A. tridentata subsp. trt-
dentata. Our chromatographic data (table 1) support their recognition of subsp. wyo-
mingensts as a valid separate subspecies and corroborate Young's (1965) thin-layer
chromatographic evidence for three subspecies. However, our data indicate that subsp.
wyomingensts has closer affinities to subsp. vaseyana than to subsp. tridentata.

14

Table 4.--Flowering dates of the chromatographic subgroups of
A. tridentata

Subgroup Flowering date
vaseyana Ic July 15-30
vaseyana la August 5-20
vaseyana Ib September 7-21
wyomtngensts Id September 7-21
tridentata Ila September 7-21
tridentata IIb September 10-October 10
tridentata IIc September 10-October 10

One of the primary genetic modifications necessary to permit the development of
short-growing-season strains in high elevations is the ability to reproduce under pre-
vailing conditions. Of interest in this regard is the early flowering of vaseyana Ic
and vaseyana Ia in contrast to the other subgroups. All seven subgroups are growing
together at Snow College Field Station, Ephraim, Utah (5,600 feet elevation). Here,
vaseyana Ic blooms as early as mid-July and vaseyana la by early August, whereas the
other subgroups are not in flower until after the first week of September (table 4).
Phenological data presented here are in general agreement with observations from
uniform gardens in northern Idaho (Winward 1970) and south central British Columbia
(Marchand and others 1966). The Canadian investigators found, as we did, early- and
late-flowering ecotypes of A. trtdentata subsp. vaseyana.

The dominant low-elevation valley big sagebrush (A. tridentata subsp. tridentata)
of the northern Great Basin is trtdentata IIb; in the southern Great Basin, however,
tridentata IIc is the common low-elevation valley big sagebrush. Small populations of
IIc can frequently be seen throughout the Great Basin as tall shrubs growing along
fence rows or in other protected areas. Tridentata IIb predominates in most low-
elevation big sagebrush sites, but it is not confined to these areas; it can be found
elsewhere in small populations intermixed with vaseyana Ia and vaseyana Ib types,
particularly in the lower foothill areas.

Subgroup tridentata IIa was collected only from localized areas of northwestern
Nevada where it grows in close association with A. tridentata subsp. wyomingensts (Id).
In fact, chromatographically, it appears to have arisen from hybridization between
wyomingensts Id and tridentata IIb since it contains characteristics common to both
(Cee eis

There is abundant chromatographic evidence that where populations of subgroups
overlap and intermix, interbreeding occurs. This is particularly evident in ecotonal
areas between populations of vaseyana Ib and tridentata IIb; chromatograms of many
specimens contain unusual combinations of spots not found in isolated, uniform popula-
tions of either subgroup (fig. 34).

The distribution of subgroups is so uniform within the Great Basin that rather
accurate predictions as to their presence can frequently be made after considering ele-
vation and topography. However, distribution outside this area appears to be more er-
ratic. For instance, only a few specimens of subgroup vaseyana Ib have been collected
from areas peripheral to the Great Basin. Collection sites outside this area, physi-
cally similar to those within the Great Basin in which this subgroup is characteristic,
are usually occupied by vaseyana Ia, the most widely distributed of the A. tridentata
subsp. vaseyana subgroups. Furthermore, 4. tridentata subsp. wyomtngensts, widely

IS

distributed in Wyoming and Montana (Beetle and Young 1965) and extending into Idaho and
Northern Nevada, is not common within the Great Basin. Brunner (1972) noted a different
ecotype of subsp. wyomtngensts in the Great Basin. Additional evidence of this change
in distribution patterns is the fact that most populations of subspecies trtdentata in
these same peripheral areas bear more chromatographic similarity to tridentata IIc than
to tridentata IIb, even though these populations occupy areas similar to those occupied
by tridentata IIb within the Great Basin. This conclusion is based on collections from
eastern Utah, southern Idaho, and parts of Wyoming.

Morphologteal aspeects.--While a thorough morphological study of the seven subgroups
of big sagebrush has not been made, the following observations have been noted. The
subgroups Ia, Ib, and Ic are undoubtedly variations within the subspecies vaseyana.

The distribution, the spatulate or broadly cuneate leaf shape (fig. 35), and the pleas-
ant mintlike fragrance of the specimens within these subgroups ‘are all characteristic

Figures 35-37.--Photographs of rep-
resentative leaves of the chromato-
graphte subgroups of A. tridentata
(scale ts tn mm). Fig. 35, from
left to right, subgroups Ie, Ia,
and Ib of subspectes vaseyana;
fig. 36, subspecies wyomingensis;
ftg. 87, from left to right, sub-
groups IIb, IIa, and IIe of sub-
spectes tridentata.

37

16

of descriptions reported for the subspecies vaseyana. However, there seems to be little
morphological difference between Ia, Ib, and Ic that can be used consistently to sepa-
rate them. Odor differences are not sufficiently characteristic to’ distinguish groups
within subspecies. Considerable variation in leaf color has been observed, but similar
shades can be found in each subgroup. Leaf size appears to be slightly reduced from

Ic to Ia to Ib as the elevation decreases (fig. 35). However, this is believed to be
mostly a reflection of the favorability of the site since the difference does not al-
ways persist when all types are grown under similar environmental conditions. Leaves

of subgroup Id (A. tridentata subsp. wyomingensts) are cuneate in form and are the
smallest in group I (fig. 36)...

Similarly, Ila, IIb, and IIc are probably different ecotypes within the subspecies
trtdentata. Leaves of IIa and IIb are cuneate, whereas those of IIc are longer and
oblanceolate (fig. 37). Subgroups IIa and IIb appear to be morphologically similar.
However, differences have been observed between them and IIc. Plants of subgroup IIc
are commonly observed along fence rows, gullies, and similar places throughout the
northern Great Basin, but are more common to the south. These plants are typically
much taller than those of Ila and IIb, frequently attaining heights of 12 to 15 feet.
Although individual plants of large populations of IIc are not generally as tall as
those growing along fence rows or in other protected places, they are somewhat taller
than similar populations of IIa or IIb. The color of IIc is quite distinct and indi-
viduals of this group can usually be distinguished from Ila and IIb by observers
acquainted with color variations in sagebrush populations. Plants of subgroups Ila
and IIb usually exhibit varying shades of gray green, whereas those of IIc are bluish

gray.

The collections studied may not have included representatives from either 4.
tridentata subsp. vaseyana f. sptctformis or A. trtdentata subsp. tridentata f.
partshtt (Beetle 1960). However, a few long-leafed, high-elevation specimens of A.
tridentata subsp. vaseyana were chromatographed. These collections were chromatograph-
ically similar to shorter-leafed A. tridentata subsp. vaseyana types and are included
in vaseyana Ic. Furthermore, plants of large stature with drooping inflorescences, a
prominent characteristic of A. tridentata subsp. tridentata f. partshitt, were collected
from the sandy areas of northwestern Nevada. Most of these were chromatographically
similar to tridentata Ila. We have assumed that these were probably not true A.
tridentata subsp. tridentata f. partshit collections.

Distrtbutton in relatton to grazing preference.--The two major chromatographic
groups, I and II, also show a pronounced difference in palatability. Almost without
exception, collections from individual shrubs or populations that normally show signs
of heavy grazing by deer and livestock, especially on winter ranges, are included in
group I. Grazing preference has been evident for many plants collected from widely
scattered areas under heavy utilization at the time of collection. On the other hand,
all collections from populations observed to be relatively unpalatable are included in
group II. The preference for group I plants, as contrasted with those of group II, was
particularly evident in the area from which wyomingensts Id and trtdentata Ila were
collected in Nevada and where these two types were growing together as an intermixed
population. Form wyomingensts Id was highly palatable to cattle that grazed the
area, but form tridentata Ila was grazed very little. Sheep and deer exhibited the
same partiality for wyomingensts Id. Similar selectivity of group I over group II has
been observed where types vaseyana Ib and trtdentata Ila come together and intermix in
lower foothill areas in the Great Basin. Under these circumstances, plants of vaseyana
Ib are grazed much more extensively than those of tridentata IIb. Intermediates result-
ing from apparent hybridization between these two strains exhibit considerable variation
in the degree to which they are grazed, but are usually preferred to the group II plants.

Table 5 illustrates the differential browsing selectivity of deer during April of
1972 for the foliage of several sources from different intermountain areas. Plants from

17

Table 5.--Uttilizatton by deer of transplanted A. tridentata on winter range near
Price, Carbon County, Utah

Accession : Place of origin : Subspecies ; Subgroup: Percent
no. : : : * uti lization
1601 Hobble Creek, Utah Co., Utah vaseyana Ta 60
2201 Indian Peaks, Beaver Co., Utah vaseyana la 45
4801 Soldier's Summit, Wasatch Co., Utah vaseyana kal 65
5701 Wallsberg, Wasatch Co., Utah vaseyana Ib Ho
6302 Leonard Creek, Humboldt Co., Nevada vaseyana Ib 95
6301 Leonard Creek, Humboldt Co., Nevada wyomingensts Id 90
3601 Trough Springs, Humboldt Co., Nevada trtdentata Ila 35
1501 Indianola, Sanpete Co., Utah tridentata . IIb 35
1701 Black Mountain, Sevier Co., Utah trtdentata IIb 10
1703 South of Manti, Sanpete Co., Utah trtdentata IIb 10
2002, | Marysvale, Piute Co., Utah tridentata IIb 20
4302— Gordon Creek, Carbon Co., Utah tridentata IIb 35
6704 Dove Creek, Dolores Co., Colorado . tridentata Ib ion? Eke 30

1 : ; : :
1/the common, native big sagebrush on this winter range.

various sources were removed from their native habitats and transplanted into adjacent
rows of about 100 plants each on Utah Division of Wildlife Resources deer winter range
northwest of Price, Utah (fig. 38). This kind of planting reduces environmental factors
(e.g., soil and climate) that might have a confounding infuence on utilization.

Although the degree that plants from one source were grazed varied considerably, a
strong preference is indicated for group I-type plants as compared to group II-type
plants (table 5, figs. 38 and 39). Older but similar plantings that have been grazed by
deer and livestock over a longer period of time substantially confirm these observations.
We have observed only one instance where grazing animals preferred group II to group I.
This exception involved 40 group II plants transplanted from a lowland black greasewood
area onto a foothill site having a prevailing group I population. In this instance,
deer showed a marked preference for the group II plants. Possibly, the different taste
of group II plants in a predominantly group I area attracted the deer.

Figure 38.--Photograph showing trans-
planted A. tridentata for deer brows-
tng selectivity experiments. Arrow,
heavily browsed A. tridentata subsp.
vaseyana subgroup Ia accesston from
Hobble Creek, Utah County, Utah; the
two rows to right of arrow, unbrowsed
A. tridentata subsp. tridentata sub-

= we group IIb accession from Indtanola,
x fae Sanpete County, Utah. Photograph
/ taken January 1971. Note the deer
LBL, / tracks.

18

Figure 39.--Photograph
showing differential
deer selectivity in
browsing A. tridentata
from different sources.
An A, tridentata subsp.
vaseyana subgroup Ib ts
on the left and an A.
tridentata subsp.
tridentata subgroup IIb
on the right.

Sect at

Fat 4 ed * ¢ f.

In summary, wyomingensts Id and vaseyana Ib are highly preferred, other vaseyana
subgroups, Ia and Ic, are moderately preferred, and subspecies trtdentata subgroups Ila,
IIb, and IIc are least preferred by grazing animals.

Occasionally, single plants or small groups of plants within large populations of
heavily grazed plants are grazed far less than the rest of the population. Several
chromatographic analyses have been made when plants that possessed similar morphological
characters have been found growing side by side, but one has been heavily grazed, the
other ungrazed. In most instances, no important variations in chromatographic patterns
were found. However, in collections of this type from lower A. tridentata subsp.
vaseyana (Ib) elevations, chromatograms of the ungrazed plants frequently show evidence
of hybridization with A. tridentata subsp. tridentata, which may account for the
difference in selectivity.

Some evidence indicates that reduced brilliance of spot 9 and the appearance of
spot 26 in A. nova (fig. 19) is also associated with decreased grazing preference.
This apparent pattern has not been conclusively demonstrated for all sources. A
similar change in chromatographic pattern was observed in A. arbuscula subsp. arbuscula
(fig. 10), but no correlation could be drawn between this characteristic and utilization
by game or livestock. Further observations will be required.

Phylogenetic relattonships.--Hall and Clements (1923) postulated the evolution of
the section Trtdentatae from the more primitive section Abrotanun. They further be-
lieved that section Tridentatae first gained a foothold in the arid southwestern United
States and later moved northward into the Great Basin as climatic conditions became
favorable for its expansion into these areas. The connecting link between the sections
Abrotanum and Tridentatae is probably A. biglovitt (Hall and Clements 1923). Artemtsta
btglovit is a fairly abundant shrub in the upper Colorado and upper Rio Grande River
drainages of Utah, Colorado, New Mexico, and Arizona. It produces ray-flowers character-
istic of Abrotanum and also the trident leaves and overall general appearance peculiar
to Tridentatae. Support for A. biglovit-like taxa as phylogenetic connectors between
the two sections, Trtdentatae and Abrotanum, is gained by A. btglovit's intermediate
characteristics. Hall and Clements (1923), Ward (1953), and Holbo and Mozingo (1965)
place A. btglovtt in section Abrotanwn, whereas Moss (1940) and Beetle (1960) place it

19

in section Trtdentatae. Chromatograms of A. biglovit express a marked resemblance to
Trtdentatae species while demonstrating less similarity toward species of Abrotanuwn
(figs. 12, 13; unpublished data’). Consequently, its inclusion in Tridentatae is
probably the more accurate arrangement and more indicative of its true relationship.

Hall and Clements (1923) also suggest that the parent big sagebrush to evolve from
A. btglovit was probably A. tridentata subsp. typtca (synonymous with subspecies tri-
dentata as described by Ward (1953) and Beetle (1960) and as used in the present paper),
principally because it appeared to have adapted to environmental conditions under which
A. bitglovit grew. Chromatographic evidence in the present study substantiates this view
and suggests that the parental big sagebrush stock was probably subgroup tridentata IIc
or unknown taxa having similar chromatographic characteristics to this subgroup (fig.
40). Chromatograms of A. biglovit and subgroup trtdentata IIc are strikingly similar.
Spot 9 is small in both, although somewhat more brilliant in A. biglovit. Chromatograms
of A. btglovit contain a large and intensely violet spot 14 and a bright blue-green spot
92. Of the seven chromatographic subgroups of big sagebrush, subgroup trtdentata IIc
alone exhibits this same combination of spots. In all other subgroups, spot 14 is blue
to blue-gray and not usually a prominent part of the chromatogram, and 92 is missing.
Furthermore, the wide distribution of trtdentata IIc-type plants in southerly localities
where A. btglovit is also quite commonly found lends emphasis to the likelihood of a
past connection between these two forms. Paradoxically, A. biglovit and tridentata IIc
exhibit little morphological similarity. Biglow sagebrush is a diminutive form, erro-
neously called black sagebrush by many. In contrast, trtdentata IIc contains the
largest specimens in the section; plants occasionally reach 12 to 15 feet in height.
Another significant point that we cannot account for is the fact that grazing animals
show high preference for A. biglovit, but low preference for big sagebrush tridentata IIc.

Subgroup vaseyana Ia probably arose as an early variant of big sagebrush and
probably represents the parent strain of the present-day subspecies vaseyana subgroups
(fig. 40). The basis for this conclusion is the chromatographic similarity of this
subgroup to other Tritdentatae species. These include A. nova, A. arbuscula, A. cana,

A. trtparttta, A. rothrockit, and A. longtloba, all of which purportedly evolved from

A. tridentata. The common occurrence of a brilliantly iridescent spot 9 in chromato-
grams of these sagebrush species suggests closer relationship to group I-type plants

(A. tridentata subsp. vaseyana and subsp. wyomingensts) than to group II-types where
spot 9 is small and exhibits little iridescence. Furthermore, considering the subgroups
of group I, none bears greater chromatographic resemblance to these species than does
vaseyana Ta. Consequently, subgroup vaseyana Ia seems to be the branch of big sagebrush
arising from tridentata IIc and the branch from which other subgroups of group I and
most of the section Trtdentatae evolved. From vaseyana Ia-type plants, which occupy

an intermediate elevational habitat, subgroups vaseyana Ib and vaseyana Ic probably
arose as modifications respectively adapted to elevational zones below and above that

of vaseyana Ia (fig. 40).

Artemisia tridentata subsp. vaseyana may have arisen before the establishment of
big sagebrush within the Great Basin since this form occurs extensively throughout the
present range of the A. tridentata complex. However, the range of vaseyana Ib is
largely restricted to habitats within the Great Basin; so this ecotype probably origi-
nated within this geographical area.

Our data coupled with that of Beetle and Young (1965) support the hypothesis that
A. tridentata subsp. wyomingensis is derived from subspecies vaseyana and tridentata
of A. tridentata and ancestral stock not unlike vaseyana subgroups Ia and/or Ib and
trtdentata subgroups IIb and/or IIc (fig. 40).

2David Hanks. 1969 chromatography information on file at Intermountain Forest and
Range Experiment Station, Ephraim, Utah.

20

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Based on cytological evidence, Taylor and others (1964) postulated the evolution
of A. tridentata subsp. trtdentata from A. tridentata subsp. vaseyana for the British
Columbia populations of these two subspecies. In British Columbia, A. tridentata subsp.
vaseyana populations are uniformly diploid, n = 9, whereas A. tridentata subsp. trt-
dentata are all tetraploid, m = 18. No introgression between subspecies was observed
by Taylor and others (1964) in contrast to the relatively common introgressed popula-
tions of the Great Basin. In the Great Basin and adjacent areas, diploid and tetraploid
populations of both subspecies occur (Ward 1953; Winward 1970; unpublished data3). No
logical pattern of chromosomal evolution is apparent for the Tridentatae as a whole
either in the Great Basin or over its complete range of distribution. A cytological
study should help to clarify the evolutionary past of the Great Basin Tridentatae.

The phylogenetic pathway of taxa similar to A. btglovit — = tridentata IIc —=
vaseyana Ia including evolutionary adaptive radiations from subgroups tridentata IIc
and vaseyana Ia is suggested for the Great Basin Tridentatae by chromatographic evidence
presented here (fig 40). Hybridization-polyploidization cycles such as exhibited in
section Trtdentatae result in reticulate evolutionary patterns (Ward 1953).

Artemisia nova, A. arbuscula, A. cana, and A. trtpartita apparently represent two
separate evolutionary lines from subgroups Vaseyana Ia (fig. 40). The latter two
species not only appear chromatographically similar to vaseyana Ia, but they largely
occupy similar habitats. Artemtsta cana and A. trtpartitta share a common chromatographic
spot, 51, which is not found in other Artemtsta species (table 1). Since it is un-
likely that the same spot should have a separate origin in each, these species probably
had a common unknown ancestor, or one evolved from A. tridentata subsp. vaseyana and
became the parent of the second. Similar problems are encountered in determining the
origin of A. nova and A. arbuscula. The common ancestry of these two species is
suggested by spots 52 and 53, not contained in chromatograms of A. tridentata subsp.
vaseyana, but present in chromatograms of both A. nova and A. arbuscula (table 1).

The connecting link to A. tridentata subsp. vaseyana may be through either of these
species or from an unknown ancestor. The older of these two lines is probably that of
A, cana and A. triparttta since these species exhibit the greatest chromatographic
dissimilarity to A. tridentata subsp. vaseyana. Artemisia nova and A. arbuscula are
more similar to A. tridentata subsp. vaseyana and so may have more recent origin.

The striking similarity of chromatograms of A. rothrockit to those of vaseyana Ia
and vaseyana Ic suggests a close relationship among them (table 1; figs. 2, 4, 23, and
40; Ward 1953; Beetle 1960). Therefore, this species must have evolved from one of the
higher elevation subspecies vaseyana types, probably vaseyana Ic, since the elevational
range of this subgroup is nearest that of A. rothrockit,

The relationship of A. pygmaea to other members of the section Tridentatae is not
clear. Rydberg (1916) placed this species in a separate section, Pygmaeae, although
more recent authors (Hall and Clements 1923; ,Ward 1953; and Beetle 1960) have considered
it to be included in Tridentatae. Beetle (1960) suggests that it may have an early
link with A. nova; however, chromatographically, there is no evidence of such a relation-
ship. Chromatograms of this species bear greater resemblance to A. biglovit or sub-
group tridentata IIc than to other Trtdentatae species (fig. 21). The individual plants
of the species tend to be dwarf and usually occur on severe sites impregnated by a
fairly high degree of alkalinity.

3E, Durant McArthur. Artemtsta cytological data on file at Intermountain Forest
and Range Experiment Station, Ephraim, Utah.

22

LITERATURE CITED

Alston, R. E.; and B. L. Turner
1962. New techniques in analysis of complex natural hybridization. Nat. Acad.
SCL. Proc. ge Us. 483 150=1357 .
Bachelor, F. W., A. B. Paralikar, and S. A. Telang
1972. Alkanes of three Artemista species. Phytochemistry 11:442-443,
Beetle, A. A.
1960. A study of sagebrush, the section Tridentatae of Artemisia.
Univ... Wyo, Agric. Exp, Stn. Bull. 3568, 88 p.
Beetle, A. A.
1970. An ecological contribution to the taxonomy of Artemtsta. Madrono 20:385-386.
Beetle, A. A., and A. Young
1965. A third subspecies in the Artemtsta tridentata complex. Rhodora 67:405-406.
Brunner, Ji. R.
1972. Observations on Artemtsta in Nevada. J. Range Manage. 25:205-208.
Clausen, J., D. D. Keck, and W. M. Hiesey
1940. Experimental studies on the nature of species. 1. Effect of varied
environments on western North American plants. Carnegie Inst. Wash.
Pubd.., 5205, 452 -p.
Diettert, R. A.
1938. The morphology of Artemtsta trtdentata Nutt. Lloydia 1:3-74.
Hall, H. M., and F. E. Clements
1923. The phylogenetic method in taxonomy. The North American species of
Artemista, Chrysothannus, and Atriplex. Carnegie Inst. Wash. Publ.
326), 3551p.
Hanks, D. L., J. R. Brunner, D. R. Christensen, and A. P. Plummer
1971. Paper chromatography for determining palatability differences in various
strains of big sagebrush. USDA For. Serv. Res. Pap. INT-101, 9 p.
Hanks, D. L., and K. R. Jorgensen
1973. Chromatographic identification of big sagebrush seed. J. Range Manage.
26:304.

ine)
WN

Holbo, H. R.
1965.

Marchand, L.
1966.

Mossi,.*B. di.
1940.

Rydberg, P.
1916.

Shafizadeh,
1970.

Shafizadeh,
1971.

, and H. N. Mozingo
The chromatographic characterization of Artemtsta, section Tridentatae.
Am. J. Bot. 52:970-978.
S., A. McLean, and E. W. Tisdale
Uniform garden studies on the Artemtsta tridentata Nutt. complex in interior
British Columbia. Can. J. Bot. 44:1623-1632.

Interxylary cork in Artemisia with a reference to its taxonomic significance.
Am. J. Bot. 27:762-768.

A.

Artemtsta and Artemistastrum. N. Am. Flora 34:244-285.

F,, and A. B. Melnikoff

Coumarins of Artemtsta tridentata ssp. vaseyana. Phytochemistry

9:1311-1316.

F., N. R. Bhadane, M. S. Morris, R. G. Kelsey, and S. N. Khanna
Sesquiterpene lactones of big sagebrush. Phytochemistry 10:2745-2754.

Taylor, R. Li, L. S. Marchand, and C. W. Crompton

1964.

Ward, G. H.
1953.

Winward, A.
1970.

Winward, A.
1969.

Young, A.
1965.

Cytological observations on the Artemista tridentata (Compositae) complex
in British Columbia. Can. J. Genet. Cytol. 6:42-45.

Artemtsta, section Sertphtdiwn, in North America. A cytotaxonomic study.
Contrib. Dudley Herb. 4:155-205.

H,

Taxonomic and ecological relationships of the big sagebrush complex in
Idaho. Ph.D. Diss., Univ. Idaho, 80 p. Univ. Microfilms, Ann Arbor, Mich.
H., and E. W. Tisdale

A simplified chemical method for sagebrush identification. USDA For. Serv.,
Intermt. Reg., Range Improv. Notes 14(3):1-4.

A chemical study of the taxonomy of section Tridentatae of the genus
Artemtsta. Wyo. Range Manage. Issue 198:2-9.

24

* U.S. GOVERNMENT PRINTING OFFICE: 1973 __ 784-485 / 20 REGION NO. 8

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-uoT]}V]oI OYousso[AYd pue soNstszojoVAKyO otydearsoyewoIiy) ‘“EL6T

YUaAWWNN Id AYYAd *V
pue ‘SNAAGLS CUVHOIY ‘YNHLYVOW LNVund ‘a ‘°T GIAVd ‘SNNVH

‘Aiqeieed ‘eyHredy “Vy ‘THporyjoI “VW ‘eprsia “y ‘vovw3id “vy
‘eqo[suc] “Vy “vurd “Vy “TIAOTSIq “WV ‘efMOSnqae “Vy “eyeWWOpPIT] vISTMOWY
‘AuadsojAyd ‘Aydearsoyeworys ‘SGUOMAAM ‘1L‘S9OL *FP8°SPSA *GUOAXO

*sutaqjyed orydeasojyeumoryo uo
postq uotoas sty} Jo AuaSoyAyd oy] Jo 1AVYO pue UOTSSNdsSIp v pue doe}eJUOp
-I1], JO sotoods jsoul Joy suvrS0yEWOTYO dATWLJWOSaadat Sapnjout Apnys
ewyL ‘euetojord Surzeas [ewe pue ‘soystrajovareyo [vorso,oydaow
‘UOIINdIIjSIp [BVOTSO]OOS YIM peayejet10o oae sdnox8qns osoyL ‘poy
-Uapl orev veep) “Vy JO sdnoar8qns o1ydeaSojewoayo udaog ‘VISTULOJIV
JO avyV op] Uooas oy] JO sTsATeuL oTydeaZojeWOTYO & ST ApNIS STYL

(LOPS YIN ‘UapsO ‘uoT}eIg JUSWIIedxY aSuey
7? \SoIOY uleyUNOUIOIUT) ‘“SniTI ‘°d FZ ‘TPI-LNI ‘ded ‘soy
“ALIS “LOT VSN ‘ovzeWopItL uotjoos ‘eIsTuaj}1y Jo sdrys
-uoT}e[oI OTJouaSo[Ayd pus sostszojovVaeyoO orydersojewoIyO ‘“EL6T
YAWANNTd AYYHd *V
pue “SNAAALS GUVHOI “YNHLYVOW LNVuNG “a ‘1 GIAVd ‘SYNVH

“Aypiquyeyed ‘eynazediay “y ‘tyooryjor ‘vy ‘tprsta “y ‘vovusid “Vy
‘eqoyisuoy “y ‘vuRd “Vy “TIAOTSIq “Vy ‘epnosnqre “Vy ‘eIeOpTA} VISTMIOIIY
‘AuosojAyd ‘Aydersoyewor1yo ‘SGUOMAAM ‘L'S9L ‘PPS ‘°StSN *GUOAXO

*suzeyjed o1ydersoj;euloaryo uo
poeseq uotjoes sity} Jo AuoSsoyAyd oy) Jo javYoO pue UOTSSNostp & puv deJeJUEp
-I1], JO satoads jsow I0J sulVASO}JBWOAYO dAT}eJUOSoId9I Sopnjour Apnys
eyL ‘eoUetejord BSuizeis [ewrue pue ‘sojstrajovaieyo [eotso,oydrouw
‘uoTNqIIj{SIp [VOTSO[ODS YIM posye[etq0d ore sdnoaSqns ssoyL ‘“poyn
-Udpt oie ByeWopta] *V Jo sdnoaSqns orpdeaSojywuioayo dA “BISTWAWAV
JO de}eWOPTLL UOTOES oY] JO stsAyTvue oTydeaSoyeworyo v st ApNis STyL

(*TOPFS YRIN ‘UspsO ‘uoTIeIS JUsUITIOdXY oSuLy
FY ySoLOT ureyunowusezuy) ‘snqt ‘°d pZ ‘TPI-LNI ‘ded ‘soy
"AIOS ‘JOY VASN ‘avyewepiL uolyoos ‘eIstmojty Jo sdiys
-UO0T}V[9I OoUuasSoTAY puv soysttajovavyo oTydersozeurotiyo) ‘“EL6T
YAWNN Id AYWHd *V
pue ‘SNAAXLS GUVHOIY ‘UNHLYVOW INvund “a ‘Tl GIAVd ‘SINVH

“Aipquyeyed ‘eynazediay “vy ‘Tppooryjor “Vy ‘eprsia *y ‘eoewskd *y

‘AuosojAyd ‘Aydvasoyeworyos ‘SGUOMAAM ‘“L'S9L ?PP8"°StSA *GHOTXO
*suzoqjed o1ydearsojyeuor1yo uo
poseq uoToos Sty] Jo AuaSoyAyd oy Jo JAVYO pu UOTSSNoSIp v puUe aeJEJUOp
=11L JO sotoods ysoul 10y sweaSoyeUIOIYO VAYVJUeSeAdoa sapntour Apnyqs
ey. ‘aouetejoid Sutzeas yTewtue pue ‘solstzojyovVarRvyoO [eorso;oydazout
‘uoTINqIAISIp TeoOTSO]OON YIM poyeToqq0o) oav sdnoasqns ossoyL ‘poyy
-uopl ore ByeWopla} ‘y Jo sdnorSqns o1yderaSoyewmoayo uoaog “vISTUO}IV
JO dvyeopILT UOTIeS oy] JO sisAyeue oTydeaS0jyeWOILYO v st ApNIs STYL
(*‘LOFPS YeIN ‘uepsO ‘uoT{eIS JUOWTIOdxY osuvy
2 YSoIOY ulequnNowodz]) ‘sny[t ‘°d FZ STFI-LNI ‘ded ‘soy
"Adag “IO VASN ‘oejeopIaL, uotoes ‘eTsTuUIOjTy Jo sdrys
-UOT]V[AI OTJoOUaSOTAY puv soystsoyoVareyo oTydearSoywMOIYO ‘“EL6T
YAWANNITd AYYHd *V
pue ‘SNHAQLS GUVHOIY ‘YNHLYVOW LNVUNC “a **1 GIAVd ‘SYNVH

Headquarters for the Intermountain Forest and
Range Experiment Station are in Ogden, Utah.
Field Research Work Units are maintained in:

Boise, Idaho

Bozeman, Montana (in cooperation with
Montana State University)

Logan, Utah, (in cooperation with Utah
State University)

Missoula, Montana (in cooperation with
University of Montana)

Moscow, Idaho (in cooperation with the
University of Idaho

Provo, Utah (in cooperation with Brigham
Young University)

Reno, Nevada (in cooperation with Uni-
versity of Nevada)

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