The Douglas-fir/pinegrass habitat type in central Idaho : succession and management

108 Pages·1993·6.6 MB·English

by  Steele, Robert W. (Robert Wilbur)

Archive Document
Historic,
Do not assume content reflects current
scientific knowledge, policies, or practices.

United States/ The
Department Douglas-fir/Pinegrass
ofAgriculture
Forest Service Habitat Type in Central
Intermountain
Research Station Idaho: Succession and
General Technical
Report INT-298 Management
May 1993
Robert Steele
fUf
SJl
Kathleen Geier-Hayes
0
THE AUTHORS for sampling. Ray Cullinane and Sharon Bradley
(Challis National Forest) offered information on
ROBERT STEELE is a research forester assigned to potential sampling areas. Ken Neiman (Northern
the Conifer Ecology and Regeneration research work
Region) provided information on sample plots in
unit at Boise, ID. Since joining the Intermountain
northern Idaho.
Research Station in 1972, he has concentrated on
development of forest habitat type classification, and
RESEARCH SUMMARY
on classification and management of successional
forest communities. He earned a B.S. degree in forest A succession classification system for the Douglas-
management and an M.S. degree in forest ecology at fir/pinegrass habitat type is presented. It is based on
the University of Idaho.
reconnaissance sampling of 167 stands: 44 old-growth
KATHLEEN GEIER-HAYES is a research forester in sites, three pairs of old-growth versus disturbance
the Conifer Ecology and Regeneration research work sites, and 1 17 additional disturbed sites. A total of 1
unit. She has worked part-time on the classification potential tree layer types, 32 shrub layer types, and 60
and management of successional forest communities herbaceous layer types are categorized by a hierarchi-
since the project's beginning in 1979. She joined the cal taxonomic classification. Diagnostic keys based on
Intermountain Station full time in 1986. She earned a indicator species are provided forfield identification of
B.S. degree in biology at Boise State University and an the layer types.
M.S. degree in forest science at the University of Idaho. Implications for natural resource management are
provided based on field data and observations. These
ACKNOWLEDGMENTS implications include: occurrence of pocket gophers
and success of tree plantations by site preparation
Financial support for this study was provided by treatments, initial growth rates of tree seedlings and
the Intermountain Region of the Forest Service, U.S. yield capability of mature trees, microsite needs of
Department of Agriculture, through a memorandum of natural tree seedlings, big-game and livestock forage
understanding with the Intermountain Research Station. preferences of shrub and herb layer types, and
Several people provided supplemental information responses of major shrub and herb layer species to
and expertise. Doug Basford (Salmon National various disturbances. Species composition data for
Forest) provided site history information for some each of the sampled tree, shrub, and herb layer types
sampled areas and suggested other areas suitable are displayed in tables.
The use oftrade orfirm names in ttiispublication is forreaderinformation
anddoes notimply endorsementby the U.S. DepartmentofAgriculture of
anyproduct orservice.
Intermountain Research Station
324 25th Street
Ogden, UT 84401
11 1
CONTENTS Page
Age to Breast Height 42
Page Site Index and Yield Capability 43
Introduction 1 Pocket Gophers 43
Methods 2 Snow Damage to Pine Plantations 45
The PSME/CARU Habitat Type 2 Competition With Tree Seedlings 46
Pinusponderosa (FIFO) Fhase 3 Big Game and Livestock 51
Calamagrostis rubescens (CARU) Phase 4 Deer 52
Festuca idahoensis (FEID) Fhase 5 Elk 52
Pachistima myrsinites (PAMY) Phase 5 Cattle 54
Agropyron spicatum (AGSP) Phase 5 Sheep 54
Arctostaphylos ava-urs/(ARUV) Fhase 5 Black Bear 55
Successional Features 6
References 55
Successional Classification 6
Appendixes:
The Tree Layer 7
A-1 Palatability ratings, constancy, and average
Size Class Notations 8 .
canopy cover (percent) of shrubs by layer
Populus tremuloides Layer Group (POTR L.G.) ..9 type in the PSME/CARU h.t., FIFO phase 59
Pinus contorta Layer Group (PICO L.G.) 10
A-2. Palatability ratings, constancy, and average
Pinusponderosa Layer Group (FIFO L.G.) 1 canopy cover (percent) of shrubs by layer
Ps(eFuSdoMtEsuLg.Ga.)menziesiiLayer Group 11 type in the PSME/CARU h.t., CARU phase 62
B-1 Palatability ratings, constancy, and average
The Shrub Layer .
1 canopy cover (percent) of herb layer species
Artemisia tridentata Layer Group (ARTR L.G.) ..14 by layer type in the PSME/CARU h.t., FIFO
Purshia tridentata Layer Group (PUTR L.G.) 16
phase 64
Ceanothus velutinus Layer Group
B-2. Palatability ratings, constancy, and average
(CEVE L.G.) 18
canopy cover (percent) of herb layer species
Ribes cereum Layer Group (RICE L.G.) 19 by layertype in the PSME/CARU h.t., CARU
Salixscouleriana Layer Group (SASC L.G.) 20
phase 73
Prunus virginiana Layer Group (FRVI L.G.) 21
C. Succession classification field form
Symphoricarpos oreoptiilus Layer Group
forthe Douglas-fir/pinegrass h.t 82
(SYOR L.G.) 21
D. List of plant species abbreviations
The Herb Layer 21
used in the text 83
Annuals Layer Group (ANN. L.G.) 24
Bromus carinatus Layer Group (BRCA L.G.) 25
TABLES
Potentilla glandulosa Layer Group
(POOL L.G.) 29 1. Elevational range and important tree
Geranium viscosissimum Layer Group species in phases of the PSME/CARU h.t 3
(GEVI L.G.) 30 2. Phase designations of the PSME/CARU
Epilobium angustifolium Layer Group
h.t. suggested by various studies 3
(EPAN LG.) 30
3. Key to tree layer groups and layertypes,
Antennaria micropiiylia Layer Group with code numbers, in the PSME/CARU h.t 9
(ANMI LG.) 31
4. Successional role of major shrub species
Apocynum androsaemifolium Layer Group in phases of the PSME/CARU h.t 1
(AFAN LG.) 31 5. Key to shrub layer groups and layertypes,
Fragaria vesca Layer Group (FRVE L.G.) 32 with code numbers, in the PSME/CARU h.t 15
Lupinusspp. Layer Group (LUF. L.G.) 33 6. Successional roles of important herb layer
CarexgeyeriLayer Group (CAGE L.G.) 33 species In phases of the PSME/CARU h.t 22
Calamagrostis rubescens Layer Group
7. Key to herb layer groups and layertypes,
(CARU L.G.) 33 with code numbers, in the PSME/CARU h.t 26
Management Implications 34
8. Occurrence of natural tree seedlings
Natural Tree Establishment and Related
(percent) by silvicultural method and
Microsites 34 overstory composition forthe FSME/
Pinus contorta 36 CARU FIFO and CARU phases 37
h.t.,
Pinusponderosa 36
9. Occurrence of natural tree seedlings
Pseudotsuga menziesii 39
(percent) by site preparation method for
Planted Tree Establishment 40 the PSME/CARU h.t., FIFO and CARU
Growth and Yield 42
phases 38
Page Page
10. Regeneration efficiency (RE) classes of 9. Succession classification diagram of the
seedbeds for natural tree seedlings in shrub layer in the PSME/CARU h.t., PlPO
the PSME/CARU h.l, PlPO and CARU phase 13
phases 38 10. Succession classification diagram of the
11 . Regeneration efficiency (RE) classes of shrub layer in the PSME/CARU h.t., CARU
shrub cover and other microsites for natural phase 14
tree seedlings in the PSME/ CARU h.t., 1 1. Succession classificationtliagram of the
PlPO and CARU phases 39 shrub layer in the PSME/CARU h.t., FEID
12. Occurrence of natural tree seedlings phase 14
(percent) by tree and shrub layer groups 12. An ARTR-RICE shrub layer type in the
in the PSME/CARU h.t., PlPO and CARU Iron Creek drainage southwest of Salmon,
phases 40 ID, in 1983 17
13. Success of tree plantations by site 13. An ARTR-CARU shrub layer type in the
treatment in the PSME/ CARU h.t., Iron Creek drainage southwest of Salmon,
PlPO phase 41 ID, in 1983 17
14. Success of tree plantations by site 14. A PUTR-PUTR shrub layertype southeast
treatment in the PSME/ CARU h.t., of Placerville, ID, in 1986 18
CARU phase 42 15. A CEVE-CEVE shrub layertype northwest
15. Growth and yield capabilities of trees of Carmen, ID, in 1983 19
in the PSME/CARU h.t 43 16. A RICE-RICE shrub layer type in the
16. Responses of major shrub and herb layer Noho Creek drainage north of Stanley, ID,
species to various disturbances in the in 1989 20
PSME/CARU h.t 47 17. Relative successional amplitudes of
17. Index classes to big game and livestock important herb layer species in the
forage preferences by shrub layer type in PSME/CARU h.t 23
the PSME/CARU h.t., PlPO phase 51 18. Succession classification diagram of the
18. Index classes to big game and livestock herb layer in the PSME/CARU h.t., PlPO
forage preferences by shrub layer type in phase 24
the PSME/CARU h.t., CARU phase 52 19. Succession classification diagram of the
19. Index classes to big-game and livestock herb layer in the PSME/CARU h.t., CARU
forage preferences by herb layer type in phase 25
the PSME/CARU h.t., PlPO phase 53 20. A POGL-POGL herb layer type on Banner
20. Index classes to big-game and livestock Ridge southeast of Lowman, ID, in 1986 30
forage preferences by herb layer type in 21 . An EPAN-CARU herb layer type north of
the PSME/CARU h.t., CARU phase 54 Idaho City, ID, in 1985 31
22. An APAN-CARU herb layer type northwest
FIGURES of Prairie, ID, in 1988 32
23. A CAGE-CARU herb layertype southwest
1. Distribution of the PSME/CARU h.t., PlPO of Placprville, ID, in 1986 34
phase and FEID phase in central Idaho 2 24. A CARU-CARU herb layertype southeast
2. Distribution of the PSME/CARU h.t., CARU of Placerville, ID, in 1986 35
phase in central Idaho 4 25. Occurrence of sites with pocket gopher
3. Relative successional amplitudes of major mounds (solid bars) and sites without mounds
tree species in the PSME/CARU h.t 6 (hollow bars) following various disturbances
4. Succession classification diagram of the tree in the PSME/CARU h.t., PlPO phase 44
layer in the PSME/CARU h.t., PlPO phase 7 26. Occurrence of sites with pocket gopher
5. Succession classification diagram of the tree mounds (solid bars) and sites without mounds
layer in the PSME/CARU h.t., CARU phase 8 (hollow bars) following various disturbances
6. Succession classification diagram of the tree in the PSME/CARU h.t., CARU phase 45
layer in the PSME/CARU h.t., FEID phase 8 27. Height-age relationships of free-growing
7. A sapling POTR-pole POTR tree layer type tree seedlings and some important shrub
southwest of Idaho City, ID, in 1986 10 species in the PSME/CARU h.t 49
8. Relative successional amplitudes of major 28a.A PSME/CARU site in 1983 about 3
shrub species in the PSME/CARU h.t 12 years after a stand-destroying wildfire 50
28b.Same site in 1989 50
The Douglas-fir/Pinegrass
Habitat Type in Central Idaho:
Succession and Management
Robert Steele
Kathleen Geier-Hayes
INTRODUCTION
the West (Layser 1974). By focusingon climax po-
Because ofthe increasingandoftenconflictingde- tential, they enable investigators to hold time con-
mands on ournaturalresources, landmanagers need stant while grouping plant communities accordingto
to predictchanges invegetationresultingfrom human their environment. Conversely, environment can be
activities. Butmanyfactors influencevegetal change. held relatively constant by focusing on one habitat
Oftenthe integral ofcause and effectas weU asran- type while studying vegetal dynamics overtime.
dom, cyclic, andtemporal relationshipsinvegetation This report explores the changes in vegetation and
dynamics are bewildering. Afirststeptowardunder- related resource values occurring overtime in one
standingthe complexity ofserai vegetationis tore- forest environment, thePseudotsuga menziesiil
duce the number ofunits by aclassification. Calamagrostis rubescens habitat type (PSME/CARU
Habitat type classifications focus on the environ- h.t.) (Steele and others 1981). Our classification ap-
mental differences affecting vegetation. They pro- proach recognizes the individual nature ofspecific
vide a logical framework for studying succession and sites interms ofexisting and potential species com-
occasionally imply successional relationships, but do position. It also recognizes that land managers need
not classify serai communities. This classification of site-specific guidelines for management. Manage-
serai vegetation is designed for general field use. ment implications for many species can be derived
The natural classifications we use have broader ap- from the species' successional strategy and reaction
plication and often allow better predictions than to a particular disturbance. This report canbe ap-
technical classifications designed for a specific use. plied to specific sites by combiningknowledge ofthe
The widely accepted habitattype system ofclassifi- successional characteristics for each major species
cation is an outstanding example ofa natural classi- either existing or potentially existing on a particular
fication. As its originators, R. and J. B. Daubenmire site. Sometimes, the preliminary nature and mea-
(1968), pointed out "... that system may be consid- ger data base require managers to regard the infor-
ered the closest to a natural one that allows the mation as no more than a tentative guide. Users
most predictions about a unit from a mere knowl- should focus on the relative nature ofdata in this
edge ofits position in the system." We developed the report, rather than the absolute values. Suggested
followingclassification with these criteria in mind. revisions and other feedback from users are always
The relative position ofa classified unitin the sys- welcome. Becausethis reportwas developedthrough
tem can help predict the successional status ofthat a series ofapproximations, itwill always be open to
unit. We found that some types ofserai vegetation further refinement.
result from a specific disturbance; other types de- This report applies one concept for classifying se-
velop mainly through uninterrupted succession. rai vegetation (Steele 1984). It recognizes the some-
These cause-and-effectrelationships are presented what independent nature ofsuccession in the tree,
in sections dealing with classification and with man- shrub, and herbaceous layers (often due to layer-
agement implications. specific disturbances such as selective tree harvest-
Vegetation is influenced by both time and environ- ing or grazing), treatingthese three successions
ment. Environment, as it affects vegetation, can be separately. It recognizes the high potential diversity
delineated by habitat types or potential climax com- ofearly and midseral vegetation and the relative for-
munities (Daubenmire 1952) that are relatively age values to livestock and big game. It also indi-
stable, barring disturbance. Time, as it relates to cates some ofthe relationships between site treat-
succession, can be delineated by community types or ment, planted tree survival, competingvegetation,
serai stages that can be obliterated, slightly altered, and pocket gopher populations. Perhaps most im-
or advanced through various disturbances. Habitat portant, it provides a common framework for com-
type classifications have proven useful in much of munication among various disciplines.
1
The objectives ofthis report are: In central Idaho, PSME/CARU is widespread, al-
1. To develop a classification ofserai plant commu- though it is rare in the Lost River Range and the
nity types in the PSME/CARU h.t. based on indica- southern halfofthe Lemhi and Beaverhead Ranges.
tor species and vegetal structure. These areas have a pronounced continental climate,
2. To identify successional relationships ofcommu- as indicated by the prevalence ofPseudotsuga/
nity types and relate these communities to the man- Juniperus communis andPseudotsugaIArnica
agement treatments that gave rise to them. cordifolia habitat types and a strongrepresentation
3. To present species composition and canopy cov- ofPinusflexilis. PSME/CARU is virtually absent in
erage information for each shrub and herbaceous such areas, both in Idaho and Wyoming. It also be-
comes scarce wherever a strong maritime influence
layer sampled and its relative value as forage forbig
game and livestock. exists, as in northern Idaho and adjacent areas.
4. To describe suitable conditions for natural and Where PSME/CARU occurs in northern Idaho, con-
artificial establishment oftree seedlings and early tiguous cooler, wetter sites are commonly anAbies
lasiocarpa habitat type with no intervening Tsuga
growth characteristics oftrees in relation to site
series (Daubenmire and Daubenmire 1968), suggest-
treatment, microsite conditions, and competing
ing a locally diminished maritime effect. In central
vegetation.
5. To provide a basis for developing preliminary Idaho, PSME/CARU is most prevalent, and likely
managementimplications by serai community type. zonal, alongthe dry eastern periphery ofmaritime
influence (fig.l). The environments immediately
METHODS eastward are continental. Thus, PSME/CARU ap-
pears to have a maritime affinity, but is best repre-
This report is the fourth ofa series on succession sented where the maritime influence is greatly
and management in forest habitat types. The meth- diminished.
ods are identical to those used previously. Method
details are available in the earliest final report
(Steele and Geier-Hayes 1987). In general, sam-
pling methods were similar to those used in the cen-
tral Idaho habitat type study (Steele and others
1981). Circular plots (375 m^ in size) were subjec-
tively located to represent the range ofsite condi-
tions and vegetal diversity characteristic ofthe habi-
tattype. Recorded observations included age oflast
disturbance, plant coverage by species, percent sur-
vival ofplanted tree seedlings, occurrence ofpocket
gopher mounds, snow damage to tree seedlings,
methods oflogging, slash disposal and site prepara-
tion, and thickness ofdufflayer. The plant coverage
data were used to develop a succession classification
(Steele 1984). They were later assembled in synthe-
sis tables (Mueller-Dombois and Ellenberg 1974)to
verify the early serai to climax arrangement of
stands as indicated by the classification.
THE PSME/CARU HABITAT TYPE
In the Northern Rockies, PSME/CARU appears to
be the most widely distributed habitat type in the
Pseudotsuga series. It ranges from southern British
Columbia (Brayshaw 1965) and eastern foothills of
the Cascade Mountains in Washington (Daubenmire
and Daubenmire 1968) to central Montana (Pfister
and others 1977) and eastern Oregon (Hall 1973;
Johnson and Simon 1987). It extends southward Figure 1—Distribution ofthe PSME/
through Idaho, encroaching into adjacent Wyoming CARU h.t., PlPO phase (•) and FEID (f)
(Steele and others 1983) and barely reaching Utah phase in central Idaho.
inthe RaftRiverRange (Mauk and Henderson 1984).
2
.
—
Table 1 Elevational range and importanttree species in phases ofthe PSME/CARU h.t.
Phase and elevational range (ft)
AGSP^ FIFO ARUV^'^ CARU FAMY FEiD
2,700- 3,500- 2,300- 4,700- 6,000- 6,200-
Treespecies 5,300 6,600 5,400 7,900 7,700 7,600
Pinusponderosa S3 S S
Larixoccidentalis (S) (s)
Pinus contorta (S) (S) (S) (S)
Populus tremuloides (S) (S) (S)
Pseudotsuga menziesii c c C c c C
'From Pfisterandothers 1977.
'FromCooperandothers 1991
= majorserai;s= minorserai; C =majorclimax; () =occursinonlypartofthephase.
The PSME/CAEU h.t. ranges in elevation from Pinusponderosa (PIPO) Phase
about 4,100 to 7,900 ft (1,250 to 2,408 m) in central
Idaho, but may occur as low as 2,300 ft (701 m) in The PIPO phase ranges from Montanathrough
northern Idaho. This broad range is segmented central Idaho, extendinginto eastern Washington
elevationally and geographically by several phases. (table 2). It is found between 4,100 and 6,600 ft
Elevational range and important serai trees ofthe (1,250 and 2,012 m) in Idaho, mainly in the west-
various phases are shown in table 1. central portion (fig. 1). It extends as low as 3,500 ft
(1,067 m) inMontana (Pfister and others 1977).
Table 2—Phase designations of PSf^E/CARU h.t. suggested by various studies
Phases None AGSP FIFO ARUV CARU PAMY FEID
British Columbia:
Tisdale and McLean 1957
lllingsworth and Arlidge 1960
Brayshaw 1965
McLean 1970 X
Alberta:
Ogilvie 1963
Stringerand LaRoi 1970
Montana:
Pfisterand others 1977
Northern Idahoand eastern Washington:
Daubenmire and Daubenmire 1968
Cooperand others 1991
Lillybridge and Williams 1984
Eastern Oregon:
Hall 1973 X
Johnson and Simon 1987 X
Central Idaho:
Steele and others 1981
Eastern Idahoand western Wyoming:
Cooper 1975 0
Steele and others 1983 X
Northern Utah:
Maukand Henderson 1984
'Apparentlya PSME/LIBOh.t. or PSMEA/ACAh.t.
=phasedefined; 0=phasesuggested bydataordescription.
3
This phase represents a warm, relatively produc-
tive segment ofthe habitat type. Consequently, it
supports the greatest number ofspecies and the
greatest complexity ofserai communities. Early
serai conditions usually support few trees, but occa-
sionally may include an open stand ofPopulus
tremuloides orPinus contorta. More often, scattered
youngPinusponderosa comprise the sparse tree
layer. Serai shrubs are particularly evident in this
phase. Their high coverages often obscure the climax
potential ofa Calamagrostis sward. Species and
coverages are a direct consequence ofthe types of
past disturbances and seed availability. Purshia tri-
dentata (from scarification) and Ceanothus velutinus
(from burning) indicate early serai conditions. They
may vary from nearly pure coverage to major compo-
nents ofa diverse shrub layer. Certain herbs also
characterize early serai conditions. Iliamna rivularis
(from burning) andPotentillaglandulosa (from
scarification) are common early serai indicators.
Where grazing is limited, Geranium viscosissimum
soon becomes an additional important component.
Mid to late serai stages may contain remnants of
previousPinus contorta orPopulus tremuloides
stands. The longer livedPinusponderosa is a major
serai tree and often codominates the site with
Pseudotsuga. The shrub layer, generated during
earlier stages, declines beneath the trees. It is char- Figure 2—Distribution of the PSME/
acterized by more persistent shrub species such as CARU h.t., CARU phase in central
Prunus virginiana, P. emarginata, Salix scouleri- Idaho.
ana, and Symphoricarpos oreophilus. None ofthese
persist indefinitely beneath a climax tree canopy.
The undergrowth gradually shifts from shrubby to Idaho and occurs as low as 4,700 ft (1,433 m) in
herbaceous. In the herbaceous layer, Calamagrostis Montana (Pfister and others 1977).
may be accompanied by conspicuous amounts of Productivity ofboth timber and browse is less
Carexgeyeri, Poa nervosa,Arnica cordifolia.Aster than in the FIFO phase. Pinus contorta is usually
conspicuus, Fragaria spp., orApocynum andro- the major serai tree, butPopulus tremuloides may
saemifolium. The relative amounts ofthese species be present. In northwestern Montana and in British
reflect the nature and intensity ofpast disturbance. Columbia where this phase also occurs, Larix occi-
In climax to near-climax condition,Pseudotsuga dentalis may occupy disturbed sites. Aless diverse
is the dominant tree. The open nature ofthe stand and often poorly developed shrub layer reflects the
greatly prolongs Pinusponderosa. Shrub layers are coolertemperatures ofthis phase. Artemisia triden-
depauperate or nonexistent. Calamagrostis, fol- tata ssp. vaseyana and Chrysothamnus invade bare
lowed closely byArnica, is most successful beneath soil exposed by burning or scarification. Ceanothus
the tree canopy, creating a sward that is characteris- velutinus germinates from buried seed following
tic ofthe habitat type. burning, but attains appreciable coverage only at
the lower, warmer extremes ofthe range ofthis
Calamagrostis rubescens (CARU) phase. Ribes cereum also germinates from buried
Phase seed and may be the dominant shrub on scarified
sites. These shrubs indicate early serai conditions,
The CARU phase is common nearthe Idaho- yet they rarely achieve densities comparable to the
Wyoming border, in east-central Idaho, and across FIFO phase. Early serai herbaceous layers may be
much ofMontana. From east-central Idaho, it oc- diverse, though seldom luxuriant. Potentillaglan-
curs westward sporadically at elevations above the dulosa, and on the cooler sites, Carex rossii, respond
limits ofPinusponderosa (fig. 2) and likely extends to scarification. On soil exposed by scarification or
into northern Idaho (table 2). It ranges in elevation burning,Antennaria microphylla can become an im-
from about 6,400 to 7,900 ft (1,951 to 2,408 m) in portant species. Bromus carinatus may increase on
4