BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Pickeringia montana | Chaparral Pea 



GENERAL BOTANICAL CHARACTERISTICS : 
Chaparral pea is a native evergreen shrub from 1.6 to 6.6 feet (0.5-2 m)
in height.  Branches are stiff and dense, with spine-tipped branchlets
[16].  The sclerophyllous leaves are 2 to 6 inches (5-15 cm) long.  The
fruit is a legume containing 6 to 10 seeds.  Root nodules are dense and
arranged in large clusters [13,22].


RAUNKIAER LIFE FORM : 
   Phanerophyte
   Cryptophyte


REGENERATION PROCESSES : 
The primary method of reproduction is vegetative.  Most sources state
that chaparral pea spreads by sprouting from the roots [4,6,20,23].
Munz [16], however, stated that it spreads from rhizomes.  Damaged
plants sprout from the roots and root crown [23,26].

Fruiting is rare [16,20].  Zedler [27] suggests that the few seeds that
do mature have high rates of sterility or low viability.


SITE CHARACTERISTICS : 
The climate in which chaparral pea grows is Mediterranean, characterized
by wet, mild winters and hot, dry summers [19].  Soils are usually low
in fertility [5].  Soil pH varies from moderately to slightly acid
[8,19].  Soil parent materials include siliceous sandstone, siliceous
shale, serpentine, and diabase [26].  Chaparral pea occurs at elevations
from 2,000 to 5,000 feet (610-1,524 m).  It is most commonly found on
ridgetops [3,13,23]

Plant associations:  Overstory associates not listed under Distribution
and Occurrence include Tecate cypress (Cupressus forbesii), Sargent's
cypress (C. sargentii), bishop pine (Pinus muricata), Coulter pine (P.
coulteri), tanoak (Lithocarpus densiflora), and California bay
(Umbellularia californica) [26,27].

Common shrub associates include Eastwood manzanita (Arctostaphylos
glandulosa), chamise, wedgeleaf ceanothus (Ceanothus cuneatus),
chaparral whitethorn (C. leucodermis), birchleaf mountain-mahogany
(Cercocarpos betuloides), sawtooth goldenbush (Haplopappus squarrosus),
poison-oak (Toxicodendron diversilobium), hollyleaf cherry (Prunus
ilicifolia), California scrub oak (Quercus dumosa), and chaparral yucca
(Yucca whipplei) [9,26].

Herbaceous associates are rare in mature chaparral stands but are common
following disturbance in the plant community [5].  Common herbaceous
associates include California goldenrod (Solidago californica), chaparral
pentstemon (Pentstemon heterophyllus), common soap-plant (Chlorogalum
pomeridianum), dove lupine (Lupinus bicolor), wild oat (Avena fatua),
ripgut brome (Bromus rigidus), soft chess (B. mollis), foothill stipa
(Stipa lepida), and smallflower milicgrass (Melica imperfecta) [19,26].


SUCCESSIONAL STATUS : 
Facultative Seral Species

Ecologists disgree as to the successional status of mixed chaparral.  It
has been variously described as climax [7], fire-climax [4], or fire
subclimax [24].  Chaparral pea is a component of mature, mixed chaparral
communities [4,24].  Following fire or other disturbance, it is a
survivor, repopulating the initial community from sprouts [4].  Seedling
colonization following disturbance is largely unstudied.  Chaparral pea
has tentatively been classified as having a low to intermediate rate of
seedling establishment in secondary succession [28].  In the absence of
fire or other disturbance, chaparral pea and associated chaparral shrubs
are replaced by oak woodland or coniferous forest [24].

Since chaparral pea grows in mixed evergreen forest, it is probably
moderately shade tolerant.


SEASONAL DEVELOPMENT : 
Chaparral pea begins growth in February [11].  Plants flower from May
through June [16].

Related categories for Species: Pickeringia montana | Chaparral Pea