BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Philadelphus lewisii | Lewis' Mockorange 



GENERAL BOTANICAL CHARACTERISTICS : 
Lewis' mockorange 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' mockorange is extremely variable in both vegetative and
floral characteristics [39].


RAUNKIAER LIFE FORM : 
   Phanerophyte


REGENERATION PROCESSES : 
Lewis' mockorange 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' mockorange 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' mockorange sprouts from the root crown [10].


SITE CHARACTERISTICS : 
Lewis' mockorange occurs on well-drained, moist sites [46].  It grows on
deep, rich alluvial loams to rocky or gravelly loams [43].  Lewis'
mockorange 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' mockorange 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' mockorange grows best on
northern and eastern exposures [43].


SUCCESSIONAL STATUS : 
Lewis' mockorange 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' mockorange 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

Related categories for Species: Philadelphus lewisii | Lewis' Mockorange