BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Pinus contorta var. contorta | Shore Pine 



GENERAL BOTANICAL CHARACTERISTICS : 
Shore pine is a short-lived, native conifer [9,22,25,43].  At maturity,
depending on the site, shore pine reaches heights of 20 to 50 feet (6-15
m) and d.b.h.'s of 6 to 20 inches (15-50 cm) [16,26,40,46].  The trunk
is often twisted, and crown shape varies from dense and round to
irregular [17,19,27].  The bark of shore pine is furrowed and up to 1
inch (2.54 cm) thick [3,9,26].  Shore pine has many branches [4,9,26].
The short, narrow leaves occur in fascicles of two [3,17,19,26,44].  The
cones are persistent [19,22,33,44,49].  They are about 1.5 to 2 inches
(3.8-5.1 cm) long [19,49].  Cones of shore pine are typically
nonserotinous [9,10,26].  Serotiny tends to increase farther inland but
is erratic and unpredictable [26].


RAUNKIAER LIFE FORM : 
   Phanerophyte


REGENERATION PROCESSES : 
Shore pine does not reproduce by sprouting [40].

Shore pine begins producing cones between 5 and 10 years of age [10,22].
Good seed crops usually occur every other year [10].  Owen and Molden
[50] discuss development of lateral shoot terminal buds.  Shore pine
produces large amounts of flowers and pollen [3,9,49].

Percentage of sound seed ranges from 75 to 79 percent [9].  Fresh seed
requires no stratification, but stored seed requires 20 to 30 days
stratification.  Seeds are viable for up to 17 years in cold storage
[22].  Seed falls approximately 200 feet (60 m) from the source under
normal conditions [9].  Shore pine requires absorbent soils, light, and
warm temperatures for germination [8,22].


SITE CHARACTERISTICS : 
Shore pine grows in a maritime climate throughout most of its range.
Annual precipitation, which falls year-round and mostly in the form of
rain, is 60 to 200 inches (1,500-5,000 mm) [15,26].  Shore pine occurs
from sea level to the subalpine zone (5,030 feet [1,525 m]) in Alaska
[3,45].  Shore pine occurs in peat bogs and muskegs on gentle slopes and
lowlands [11,19,40,42,49].  It is most common on poorly drained, deep
Histosols [11,42,45].

Conditions are xeric in the southern-most part of shore pine's
distribution, where it occurs in closed-cone pine and cypress
communities of California [48].  Shore pine habitat here includes
coastal dunes, seaside bluffs, and exposed rocky headlands; winds may be
strong and salty [48].  Soils are Inceptisols, Alfisols, and Ultisols;
best growth is on well-drained loams with a pH of 5 [16,26].  Here shore
pine occurs at elevations between sea level and 1,690 feet (0-507 m)
[33].

Overstory and understory tree species not mentioned in Distribution and
Occurrence include yelow cedar (Chamaecyparis nootkatensis), Mendocino
White Plains lodgepole pine, bishop pine (Pinus muricata), and common
juniper (Juniperus communis) [20,34,47].  Associated shrubs are
huckleberries (Vaccinium spp.), bog Labrador-tea (Ledum groenlandicum),
bog kalmia (Kalmia polifolia), northern twinflower (Linnaea borealis),
bunchberry dogwood (Cornus canadensis), and crowberry (Empetrum nigrum)
[1,8,41,46,47].  Commonly associated herbs are sedges (Carex spp.),
naked sedge (Calamagrostis nutkatensis), rusty menziesia (Menziesia
ferruginea), and narrowleaf cottonsedge (Eriophorum angustifolium)
[8,46,47].  Sphagnum moss (Sphagnum spp.) is a common associate in
Alaska [46,47].


SUCCESSIONAL STATUS : 
Facultative Seral Species

Shore pine occurs in extreme habitats that are unfavorable to other,
potentially competitive species [9,49].  Windthrow and landslides are
common [15].

Shore pine is a climatic climax in bog woodlands, reproducing under its
own canopy [36].  Shore pine is considered a climax species in many
areas [6,41,46].

Shore pine is shade intolerant [25,26,40].



SEASONAL DEVELOPMENT : 
Male and female strobili are initiated late in the growing season.
Development continues in the spring [26].  Pollen shedding begins in mid-
to late May [9,10,26].  Cones mature between September and October, with
seed dispersal following shortly afterward [22,26,40].

Related categories for Species: Pinus contorta var. contorta | Shore Pine