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SPECIES:  Philadelphus lewisii
Creative Commons image by Dave Powell, USDA Forest Service (retired), Bugwood.org.

 


Introductory

SPECIES: Philadelphus lewisii
AUTHORSHIP AND CITATION : Carey, Jennifer H. 1995. Philadelphus lewisii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.usda.gov/database/feis/plants/shrub/philew/all.html [].
ABBREVIATION : PHILEW SYNONYMS : Philadelphus californicus Benth. [18] SCS PLANT CODE : PHLE4 PHLEA PHLEE PHLEG2 PHLEH PHLEI PHLEL2 PHLEO PHLEP2 PHLEP3 COMMON NAMES : Lewis' mock orange mockorange syringa Gordon's mockorange TAXONOMY : The currently accepted scientific name for Lewis' mock orange is Philadelphus lewisii Pursh (Hydrangeaceae) [14,15,18]. Recognized varieties [18] and subspecies [14,32] are as follows: Philadelphus lewisii var. angustifolius (Rydb.) Hu Philadelphus lewisii var. ellipticus Hu Philadelphus lewisii var. gordonianus (Lindl.) Jepson Philadelphus lewisii var. helleri (Rydb.) Hu Philadelphus lewisii var. intermedius (A. Nels.) Hu Philadelphus lewisii var. lewisii Pursh Philadelphus lewisii var. oblongifolius Hu Philadelphus lewisii var. parvifolius Hu Philadelphus lewisii var. platyphyllus (Rydb.) Hu Philadelphus lewisii subsp. californicus (Benth.) Munz. LIFE FORM : Shrub FEDERAL LEGAL STATUS : No special status OTHER STATUS : No entry


DISTRIBUTION AND OCCURRENCE

SPECIES: Philadelphus lewisii
GENERAL DISTRIBUTION : Lewis' mock orange occurs in the northwestern United States and southern Canada. It occurs from extreme southern British Columbia south to California, and east to north and central Idaho, western Montana, and southwestern Alberta [14,15,34]. Philadelphus lewisii ssp. californicus occurs from the southern Cascade Range of southwestern Oregon south through the Sierra Nevada to Tulare County, California [14,32], and P. l. var. gordonianus occurs in the Coast Ranges and the Cascade Range from British Columbia south to northern California [43].
Distribution of Lewis' mock orange. Map courtesy of USDA, NRCS. 2018. The PLANTS Database. National Plant Data Team, Greensboro, NC [44].
ECOSYSTEMS : 
   FRES20  Douglas-fir
   FRES21  Ponderosa pine
   FRES22  Western white pine
   FRES23  Fir-spruce
   FRES25  Larch
   FRES28  Western hardwoods
   FRES29  Sagebrush
   FRES34  Chaparral-mountain shrub
   FRES36  Mountain grasslands


STATES : 
     CA  ID  MT  OR  WA  AB  BC



BLM PHYSIOGRAPHIC REGIONS : 
    1  Northern Pacific Border
    2  Cascade Mountains
    4  Sierra Mountains
    5  Columbia Plateau
    8  Northern Rocky Mountains


KUCHLER PLANT ASSOCIATIONS : 
   K010  Ponderosa shrub forest
   K011  Western ponderosa forest
   K012  Douglas-fir forest
   K013  Cedar-hemlock-pine forest
   K014  Grand fir-Douglas-fir forest
   K025  Alder-ash forest
   K026  Oregon oakwoods
   K028  Mosaic of K002 and K026
   K034  Montane chaparral
   K051  Wheatgrass-bluegrass
   K055  Sagebrush steppe


SAF COVER TYPES : 
   210  Interior Douglas-fir
   212  Western larch
   213  Grand fir
   219  Limber pine
   221  Red alder
   222  Black cottonwood-willow
   227  Western redcedar-western hemlock
   229  Pacific Douglas-fir
   230  Douglas-fir-western hemlock
   233  Oregon white oak
   234  Douglas-fir-tanoak-Pacific madrone
   237  Interior ponderosa pine
   244  Pacific ponderosa pine-Douglas-fir
   245  Pacific ponderosa pine


SRM (RANGELAND) COVER TYPES : 
   109  Ponderosa pine shrubland
   203  Riparian woodland
   209  Montane shrubland
   421  Chokecherry-serviceberry-rose
   422  Riparian


HABITAT TYPES AND PLANT COMMUNITIES : 
Lewis' mock orange commonly occurs in open coniferous forests and at
forest edges [34], and is usually associated with other shrubs.  In dry
Douglas-fir (Pseudotsuga menziesii) forests on the western slope of the
Cascade Range in Oregon, Lewis' mock orange is positively (significant at
P<0.05) associated with beaked hazelnut (Corylus cornuta), oceanspray
(Holodiscus discolor), poison-oak (Toxicodendron diversilobum), baldhip
rose (Rosa gymnocarpa), and hollyleaved barberry (Mahonia aquifolium).
It reaches its greatest importance in the Douglas-fir/hollyleaved
barberry/disporum (Disporum spp.) community type [26].  Lewis'
mock orange is positively (significant at P<0.05) associated with
ninebark (Physocarpus malvaceus) on talus slopes in western Montana [25].

Lewis' mock orange occurs in moist draws and riparian areas, especially
in drier regions of the Northwest.  In eastern Oregon, Lewis' mock orange
is associated with willows (Salix spp.), alders (Alnus spp.), and
hawthorns (Crataegus spp.) [13].  It occurs with red-osier dogwood
(Cornus sericea) and Saskatoon serviceberry (Amelanchier alnifolia) in
north-central Washington [6].  It occurs with Saskatoon serviceberry and
common chokecherry (Prunus virginiana) on rocky outcrops of the National
Bison Range in western Montana [29].  In Oregon white oak (Quercus
garryana) woodlands in northern California, Lewis' mock orange occurs
along stream channels with oceanspray, cluster rose (R. pisocarpa), pale
serviceberry (A. pallida), and Indian plum (Oemleria cerasiformis).  A
Lewis' mock orange/brittle bladderfern (Cystopteris fragilis) community
type has been described [41].

Lewis' mock orange occurs in seral shrubfields and chaparral communities.
In northern Idaho, Lewis' mock orange is a component of the tall shrub
union that follows logging and burning [48].  In southwestern Oregon,
Philadelphus lewisii ssp. californicus occurs in chaparral dominated by
wedgeleaf ceanothus (Ceanothus cuneatus).  Other shrubs present include
skunkbush sumac (Rhus trilobata), yerba santa (Eriodictylon
californicum), chaparral honeysuckle (Lonicera interrupta), Klamath plum
(P. subcordata), hollyleaf redberry (Rhamnus crocea ssp. ilicifolia),
and pale serviceberry [7].

MANAGEMENT CONSIDERATIONS

SPECIES: Philadelphus lewisii
IMPORTANCE TO LIVESTOCK AND WILDLIFE : Lewis' mock orange is of minor importance as a forage species for livestock [43]. Sampson [36] considered it poor to useless browse for cattle and horses. However, Shaw [37] reports that in riparian areas in eastern Oregon, Lewis' mock orange is heavily browsed in areas accessible to cattle. Lewis' mock orange is a moderately important winter forage species for deer and elk in the northern Rocky Mountains. In southern British Columbia, Lewis' mock orange is of moderate importance as a winter forage species for white-tailed deer and Rocky Mountain elk, and of low importance to other wild ungulates [4]. In Montana, a 1957 study based on rumen samples showed that Lewis' mock orange constituted 2 percent of mule deer diets in the winter and a trace in the summer [47]. In northern Idaho, use by white-tailed deer was moderate, although a few individual plants were browsed heavily [42]. Lewis' mock orange seeds are eaten by quail and squirrels [46]. PALATABILITY : Although generally considered of low palatability, Lewis' mock orange is browsed heavily at times [21,37,42,43]. New sprouts of Lewis' mock orange are very palatable [1,21,36]. See FIRE MANAGEMENT for discussion of Lewis' mock orange palatability following fire. NUTRITIONAL VALUE : NO-ENTRY COVER VALUE : Lewis' mock orange occurs in dense shrub habitats which probably provide good cover for wildlife. In north-central Washington, Lewis' mock orange occurs in a riparian cover type which is preferred in both summer and winter by mule deer for thermal and security cover [6]. VALUE FOR REHABILITATION OF DISTURBED SITES : NO-ENTRY OTHER USES AND VALUES : Native Americans used the strong, hard branches of Lewis' mock orange for bows, arrows, combs, tobacco pipes, cradles, and netting shuttles [17,34]. Lewis' mock orange is cultivated as an ornamental, but Philadelphus coronarius, a European species, is the most commonly grown mock orange in the Northwest [39]. Lewis' mock orange is the Idaho state flower [17]; it is illegal to collect Lewis' mock orange in Idaho for export or sale [30]. OTHER MANAGEMENT CONSIDERATIONS : Lewis' mock orange is very sensitive to herbicide sprays [2,31]. Effects of herbicides on Lewis' mock orange are described [27].

BOTANICAL AND ECOLOGICAL CHARACTERISTICS

SPECIES: Philadelphus lewisii
GENERAL BOTANICAL CHARACTERISTICS : Lewis' mock orange is a native, deciduous, erect to spreading shrub that grows 3 to 10 feet (1-3 m) tall. The showy flowers occur in clusters of three to fifteen. The fruit is a four-chambered capsule about 0.24 to 0.39 inch (0.6-1 cm) long [34]. Seeds are about 0.08 inch (0.2 cm) long. Lewis' mock orange is extremely variable in both vegetative and floral characteristics [39]. RAUNKIAER LIFE FORM : Phanerophyte REGENERATION PROCESSES : Lewis' mock orange reproduces vegetatively and by seed. Seeds accumulate in the seedbank. Sparsely distributed viable seeds were collected from the top 2 inches (5 cm) of soil in forested sites in central Idaho [19] Stratification of Lewis' mock orange increases germination. Seeds stratified for 8 weeks at 41 degrees Fahrenheit (5 deg C) then placed in a sand medium at 72 to 79 degrees Fahrenheit (22-26 deg C) had 64 percent germination. The germination rate was less than 10 percent for seeds stratified less than 8 weeks [39]. Germination was 52 percent when stored at room temperature for 3 years and 39 percent when stored at 40 degrees Fahrenheit (4 deg C) [28]. Germination was low when seeds were fully exposed to light or kept in complete darkness [39]. Fruit development was adversely affected by drought in northern Idaho. Fruit partially developed, turned brown, and opened, but no viable seed was produced [8]. Lewis' mock orange sprouts from the root crown [10]. SITE CHARACTERISTICS : Lewis' mock orange occurs on well-drained, moist sites [46]. It grows on deep, rich alluvial loams to rocky or gravelly loams [43]. Lewis' mock orange is commonly found on rocky sites, at the base of talus slopes and cliffs, along streams, and in seasonally moist draws [6,15]. It is found at talus margins in the Columbia River Basin [11]. It occurs at seeps, springs, and rocky wet areas in the Crooked River National Grasslands in central Oregon [16]. Lewis' mock orange occurs from sea level up to 7,000 feet (2,100 m) in the Cascade Range [15,43]. Philadelphus lewisii ssp. californicus grows from 1,000 to 5,000 feet (300-1,500 m) elevation on rocky slopes and in canyons in the Sierra Nevada [36]. Lewis' mock orange grows best on northern and eastern exposures [43]. SUCCESSIONAL STATUS : Lewis' mock orange is tolerant of moderate shade [43]. It is an early to mid-seral species [38] and is often present in seral shrub communities following logging and burning [48]. Although normally scattered at low densities [43], it sometimes occurs in dense, localized stands [17]. SEASONAL DEVELOPMENT : Flowering of Lewis' mock orange occurs from May through July. Fruit matures in late summer and seeds are dispersed in September or October [39]. The following dates are general ranges drawn from several studies in northern Idaho. Specific times for several years are reported [8,33]. Development Date of Occurrence bud burst early April leaf out late April to early May leaf growth late April to mid-May stem elongation early May to late May flower bloom late June to July fruit development begins in July leaf fall late September to late November

FIRE ECOLOGY

SPECIES: Philadelphus lewisii
FIRE ECOLOGY OR ADAPTATIONS : Lewis' mock orange occurs in both forested environments which frequently experience fire and on rocky scree slopes which may not burn at all. In western Montana, Lewis' mock orange occurs in Douglas-fir habitat types which had historical fire frequencies of 5 to 45 years [10]. The ability of Lewis' mock orange to sprout after top-kill by fire enables it to persist in these forests. FIRE REGIMES : Find fire regime information for the plant communities in which this species may occur by entering the species name in the FEIS home page under "Find Fire Regimes". POSTFIRE REGENERATION STRATEGY : Tall shrub, adventitious-bud root crown Ground residual colonizer (on-site, initial community)

FIRE EFFECTS

SPECIES: Philadelphus lewisii
IMMEDIATE FIRE EFFECT ON PLANT : Lewis' mock orange is top-killed by fire, but the root crown usually survives and produces sprouts [10,23,24]. DISCUSSION AND QUALIFICATION OF FIRE EFFECT : NO-ENTRY PLANT RESPONSE TO FIRE : Lewis' mock orange sprouts vigorously from the root crown following fire [10,23,24]. After an April fire on a south-facing slope in north-central Idaho, Lewis' mock orange increased to prefire densities by the third postfire growing season [22]. The following two studies have investigated the sprouting response of Lewis' mock orange to fire. Seral brushfields within the grand fir (Abies grandis)/pachistima (Pachistima myrsinites) habitat type in northern Idaho were burned in either spring (late March - early April) or fall (October). Temperatures during the fires ranged from 67 to 78 degrees Fahrenheit (19-26 deg C), and relative humidities ranged from 25 to 48 percent. Lewis' mock orange on sites burned in October did not sprout until the following April. Lewis' mock orange on the spring-burned sites sprouted 4 to 8 weeks after the fire. Twenty completely top-killed Lewis' mock orange (eleven on the fall burned sites and nine on the spring burned sites) were measured at the end of the first postfire growing season [24]: Fall Fires Spring Fires Average crown diameter (ft) prefire 4.7 (143 cm) 4.7 (143 cm) postfire 2.4 (73 cm) 2.2 (67 cm) Average crown height (ft) prefire 8.8 (268 cm) 9.6 (293 cm) postfire 4.1 (125 cm) 3.7 (113 cm) No. basal sprouts per plant prefire 1.5 0.6 postfire 38.0 28.9 Average postfire sprout height (ft) 2.4 (73 cm) 2.1 (64 cm) A multiple regression equation is presented which relates the number of postfire basal sprouts to prefire crown height, crown diameter, and crown volume [24]. In another study in north-central Idaho, a brushfield was burned three times at 5-year intervals (31 March 1965, 3 May 1970, and 14 May 1975). Maximum air temperatures during the fires were 77, 81, and 88 degrees Fahrenheit (25, 27, and 31 deg C), and relative humidities at 4:00 pm were 35, 16, and 27 percent, respectively. Leaves on shrubs and succulent herbaceous growth depressed the fire in 1975. A single Lewis' mock orange was followed during the study. The plant was dormant during the first fire, but leaves were beginning to emerge at the time of the second fire and were completely emerged at the time of the third fire. With each successive fire, average sprout height decreased. Reduced growth following the second and third fires may have resulted from the advanced phenological stage at the time of those fires. Sprout height and number were measured the first growing season following each fire. Crown height and diameter were measured during the second postfire growing season [23]. No. basal sprouts Average sprout height (ft) 1965 14 2.0 (61 cm) 1970 19 1.5 (46 cm) 1975 16 1.0 (30 cm) Crown height (ft) Crown diameter (ft) prefire 7.0 (213 cm) 1.5 (46 cm) 1966 4.0 (122 cm) 2.0 (61 cm) 1971 2.5 (76 cm) 2.0 (61 cm) 1976 2.5 (76 cm) 1.5 (46 cm) DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : NO-ENTRY FIRE MANAGEMENT CONSIDERATIONS : Lewis' mock orange palatability increases following fire. After a spring fire in northern Idaho, utilization of Lewis' mock orange by Rocky Mountain elk was significantly (p<0.05) greater on recently burned sites than on adjacent unburned sites [21]. % of available twigs browsed 1st season 2nd season Control 1.3 0.6 Burn 36.3 30.0 Allometric equations, which can be used to estimate fuel quantities, have been developed for Lewis' mock orange. The equations use basal stem diameter to estimate foliage biomass and total biomass [5].

References for species: Philadelphus lewisii


1. Asherin, Duane A. 1975. Changes in elk use and available browse production on north Idaho winter ranges following prescribed burning. In: Hieb, S., ed. Proceedings, elk logging-roads symposium; [Date of conference unknown]; Moscow, ID. [Place of publication unknown]: [Publisher unknown]. 122-134. [17049]
2. Balfour, Patty M. 1989. Effects of forest herbicides on some important wildlife forage species. Victoria, BC: British Columbia Ministry of Forests, Research Branch. 58 p. [12148]
3. Bernard, Stephen R.; Brown, Kenneth F. 1977. Distribution of mammals, reptiles, and amphibians by BLM physiographic regions and A.W. Kuchler's associations for the eleven western states. Tech. Note 301. Denver, CO: U.S. Department of the Interior, Bureau of Land Management. 169 p. [434]
4. Blower, Dan. 1982. Key winter forage plants for B.C. ungulates. Victoria, BC: British Columbia Ministry of the Environment, Terrestrial Studies Branch. [17065]
5. Brown, J. K. 1976. Estimating shrub biomass from basal stem diameters. Canadian Journal of Forest Research. 6: 153-358. [10107]
6. Carson, Robert G.; Peek, James M. 1987. Mule deer habitat selection patterns in northcentral Washington. Journal of Wildlife Management. 51(1): 46-51. [608]
7. Detling, LeRoy E. 1961. The chaparral formation of southwestern Oregon, with considerations of its postglacial history. Ecology. 42(2): 348-357. [6360]
8. Wagonfehr, Bob. 1987. Chaparral and the Tonto land management plan. In: Wagner, Michael R., ed. Challenges and opportunities in chaparral management: Proceedings of the Southwestern Society of American Foresters annual fall meeting; 1986 November 12-14; Prescott, AZ. SAF Publication No. SAF 87.10. Flagstaff, AZ: Northern Arizona State University and the San Francisco Peaks Chapter of the Society of American Foresters: 14. [5654]
9. Eyre, F. H., ed. 1980. Forest cover types of the United States and Canada. Washington, DC: Society of American Foresters. 148 p. [905]
10. Fischer, William C.; Bradley, Anne F. 1987. Fire ecology of western Montana forest habitat types. Gen. Tech. Rep. INT-223. Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Research Station. 95 p. [633]
11. Franklin, Jerry F.; Dyrness, C. T. 1973. Natural vegetation of Oregon and Washington. Gen. Tech. Rep. PNW-8. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station. 417 p. [961]
12. Garrison, George A.; Bjugstad, Ardell J.; Duncan, Don A.; [and others]. 1977. Vegetation and environmental features of forest and range ecosystems. Agric. Handb. 475. Washington, DC: U.S. Department of Agriculture, Forest Service. 68 p. [998]
13. Heady, Harold F., ed. 1988. The Vale rangeland rehabilitation program: an evaluation. Resour. Bull. PNW-RB-157. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station; U.S. Department of the Interior, Bureau of Land Management. 151 p. [5726]
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16. Hopkins, William E.; Kovalchik, Bernard L. 1983. Plant associations of the Crooked River National Grassland. R6 Ecol 133-1983. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Region. 98 p. [1193]
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19. Kramer, Neal B.; Johnson, Frederic D. 1987. Mature forest seed banks of three habitat types in central Idaho. Canadian Journal of Botany. 65: 1961-1966. [3961]
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23. Leege, Thomas A. 1979. Effects of repeated prescribed burns on northern Idaho elk browse. Northwest Science. 53(2): 107-113. [5116]
24. Leege, Thomas A.; Hickey, William O. 1971. Sprouting of northern Idaho shrubs after prescribed burning. Journal of Wildlife Management. 35(3): 508-515. [1437]
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