Shore pine (figure 1) is a subspecies of lodgepole pine that inhabits the coastal strip in Oregon. Insect pests, diseases,
and nonbiological (abiotic) factors may have
an impact on growth, visual appearance, and
productivity of trees. However, shore pine is
quite a vigorous tree and tolerates conditions
most other trees could not. Perhaps the most
commonly observed problems of shore pine are
salt damage and shade (lack of full sun), both
factors that may be confused with insect or
disease damage. Biotic problems such as the pitch
masses of the sequoia pitch moth, the roundish
swellings (caused by western gall rust), reddish
needles and poor needle retention (caused by
foliage diseases) and the smaller pitch masses
at the base of the tree (caused by red turpentine
beetle) are commonly observed but rarely kill the
tree. In this publication, we review the general
nature of shore pine in Oregon and the common
nonbiological, insect pest, and disease problems
that impact tree health.
James E. Reeb, Extension forester, Lincoln County
Extension, Oregon State University. David C. Shaw,
Extension forest health specialist, Department of Forest
Engineering, Resources, and Management, Oregon State
University. Unless otherwise noted, photos are by one of
the authors, © Oregon State University.
Common insect pests and
diseases of shore pine on
the Oregon coast
Figure 1. Shore pine on Battle Rock in Port Orford, Oregon.
EM 9008 • September 2010
James E. Reeb and David C. Shaw
(Pinus contorta Douglas ex. Louden var. contorta)
Shore Pine in Oregon
Lodgepole pine has the widest range of
environmental tolerance of any North American
conifer. Because of this, the species is widely
distributed throughout western North America.
Lodgepole pine is a two-needled pine that is
characterized as a hard pine or a yellow pine.
Lodgepole pines can be found growing in the Rocky
Mountains, Sierra Nevada, and the mountains and
coasts of Oregon. Their range extends from Alaska
to Mexico. It is the only conifer that is native to both
Alaska and Mexico. Lodgepole pines vary in growth
rate and form, depending on location. Lodgepole
pine has four geographic varieties: P. contorta var.
contorta, the coastal form known as shore pine,
beach pine, or coast pine; P. contorta var. bolanderi, a
Mendocino County White Plains form in California
called Bolander pine; P. contorta var. murrayana
in the Sierra Nevada, called Sierra lodgepole pine
or tamarack pine; and P. contorta var. latifolia, the
inland form often referred to as Rocky Mountain
lodgepole pine or black pine. Although the coastal
form grows mainly between sea level and 2,000 ft
(610 m), the inland form is found from 1,600 to
12,000 ft (490 to 3,660 m).
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In much of its range lodgepole pine is an
important commercial timber species. Lodgepole
gets its name from the fact that Native Americans
used its straight slender boles as poles for their
teepees. It is an aggressive and hardy tree capable
of restocking cutover land in a short time. These
trees often reach heights of 80 ft and diameters of
30 in. They are characterized by long clear boles and
short, narrow open crowns. Bark beetles and dwarf
mistletoe are major damage agents of lodgepole
pine outside the coastal areas, while the thin bark
of lodgepole pine makes it easily killed by wildfire.
Along the coast, bark beetles, dwarf mistletoe, and
fire are not very important.
Shore pine
Lodgepole pines growing along the coast of
the Pacific Northwest are called shore pine and
sometimes beach pine or coast pine. Shore pine
(Pinus contorta Douglas ex. Louden var. contorta) is
a small tree that rarely exceeds 60 ft in height. Shore
pine can vary from a shrub form on exposed coastal
bluffs (figure 2), a dwarf tree planted on sand dune
areas (figure 3), or tall trees growing in protected
sites (figure 4). It is characterized by a short, often
“contorted” bole with a dense irregular crown of
twisted branches. In maturity, the crown becomes
conical. The Latin word contorta means contorted
or twisted and refers to the irregular crown of the
typical, scrubby shore pine. They have little to no
commercial timber value; however, the trees are
greatly prized for their aesthetic characteristics
and are important ornamental yard trees. They are
important trees for wildlife, because the pine nuts
are a favorite food of squirrels and songbirds.
Shore pines are often found on histosols (peat
bogs or muskegs) in southeastern Alaska, British
Columbia, and western Washington, and on dry,
sandy, or gravelly sites in western Oregon and
farther south along the coast on inceptisols, alfisols,
and ultisols. Shore pine can be found growing with
Douglas fir, Sitka spruce, western hemlock, western
red cedar, redwood, and Port Orford cedar. On
protected sites, shore pine will be replaced by these
species, whereas on dune and bluff sites, it is the
only tree that can grow there.
Shore pine needles occur two to a bundle and
are typically 1 to 3 in long (2.5 to 7.5 cm), stout and
somewhat flattened, and often appear twisted along
their length. Shore pines start producing cones when
Figure 4. Tall stature trees in Honeyman State Park,
Oregon.
Figure 2. Shore pine at the coastal edge, near Gold Beach,
Oregon.
Figure 3. Shore pine planted in sand dunes, near Dune
City, Oregon.
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they are between 5 and 10 years old. Shore pines are
monoecious; that is, they have both male and female
flowers on the same tree. Male flowers are yellow,
cylindrical and clustered at branch tips, while female
flowers are reddish purple at branch tips and appear
in the upper crown. Female flowers become prickly
cones that are 1 to 2 in long (2.5 to 5 cm) and egg-
shaped. These cones are attached to the branches in
pairs without stalks and measure 0.8 to 2.4 in long
(2 to 6 cm). They are brownish orange when ripe
and tend to point backward toward the main trunk.
Some cones will open and release seed soon after
maturing, while others can remain unopened for
several years. The winged seeds are about 0.2 in long
(5 mm).
Because lodgepole pine occupies such a variety of
sites, when planting shore pine trees it is important
that the seed or seedling source matches the site
where the pines are being planted. A study of shore
pines on Vancouver Island found that seed should
not be transferred more than 500 ft in elevation. It
could be moved 1.5° north or south but only a short
distance east and west. The researchers concluded
that seed used at their research site should come
only from sites within the narrow rain shadow of
Vancouver Island (Ying and Liang 1994). Sorensen
(1992) and Stoneman (1984) both concluded
that Sierra lodgepole pine in Oregon could be
moved over large geographical areas, but should
be restricted to narrow elevation differences. If a
lodgepole seedling from the Blue Mountains in
eastern Oregon is moved and planted on the Oregon
coast, its chances of survival are minimal. Even our
native shore pines can be damaged and sometimes
killed when large storms move large amounts of salt
spray inland. An imported lodgepole seedling does
not stand a chance in our coastal environment.
Landscape vs. natural settings
Shore pine in the landscape is an important
ornamental tree for homeowners (figure 5). As a
yard tree, shore pine can attain heights of 40 ft or
more. Even as a yard tree, its form is very often not
straight, or it is purposely formed into contorted
shapes. Some yard trees are pruned and may not
have limbs for much of the length up the trunk.
In contrast, natural shore pine can occur in dense
stands along the coast. Canopy closure may happen
when the trees are very short, often less than 20 ft
tall. The lower branches extend to the ground and
die from shade after canopy closure. The result is a
thick dense stand with dead limbs extending from
the ground level to the upper canopy, where live
limbs still support needles capable of gathering
sunlight for photosynthesis. Under this closure, very
little other vegetation can survive. Many older shore
pine stands, however, have even-sized trees that are
widely spaced, each tree with a distinctive rounded
crown and contorted branches. The understory may
be thick with evergreen shrubs (salal, evergreen
huckleberry, and rhododendron; figure 6). Most
insects and diseases go unnoticed in natural stands,
whereas the slightest impact on a specimen tree or
on a yard tree may cause worry.
Figure 5. Shore pine in a yard, Port Orford, Oregon.
Figure 6. Shore pine and understory of salal, evergreen
huckleberry, and rhododendron, Honeyman State Park,
Oregon.
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Common problems of shore pine
In the following section, we discuss major
nonbiological problems of shore pine, followed by
insects, and then diseases. Nonbiological problems
such as shading or salt spray may appear as insect or
disease damage, or one may find a biotic agent on a
tree because it is stressed by abiotic factors.
Major Nonbiological Problems of
Shore Pine (see table 1)
Table 1. Nonbiological problems that can impact shore
pine and be confused with insects and disease.
Cause Symptoms and description
Salt damage
Reddish foliage, often on one side of the tree. The
canopy can have a burned look.
Trees often recover. Associated with winter storms that
blow salty water onto land.
Shade
Poor growth, spindly branches, crown uneven and
lacking fullness. May have foliage diseases. Shore pine is
a sun-loving plant and does poorly in shade.
Overwatering
in lawns
Sudden death. Crown becomes red and foliage dies.
Roots develop poorly. Watering shore pine in lawn
settings is hard on the tree, as they are adapted to the
dry Oregon summer/fall. Watering can increase root
diseases such as Phytophthora spp. and Armillaria.
Death is associated with poor root development.
Planting
potted trees
After planting, the tree fails to develop and eventually
dies, or one part of the crown dies. Potted trees may
have constricted roots from being in the pot too long.
When planting this type of tree, be sure to break up the
bound roots and see that the root ball is not shaped like
the pot.
Trenching/
construction
damage
Tree declines and may die. Trenching can damage major
roots, thus weakening tree vigor and possibly allowing
entrance courts for root and butt rots. All roots serve
the crown of the tree, and the size of the below-ground
water and nutrient-uptake apparatus (roots) is related
to the size of the crown. When roots are severed, the
remaining roots may be unable to service the entire
crown as before.
Improper
pruning
Pitch moths common on pruning wounds. Persistant
wound occurs. Pruning should occur from October to
February. Avoid damaging branch collar.
Off-site
planting
Tree declines and dies. Foliage disease causes foliage
loss, tree just seems weak and never vigorous. Ask
about the genetics of the tree before purchasing. (What
is the seed source of this tree?)
Salt damage
Salt damage to shore pine is a common
phenomenon along the Oregon coast in certain
years. Violent storms and high winds along the
coast pick up salt spray (usually in winter) and can
blow this material inland a considerable distance.
Salt interferes with normal biological function of
the needle and will kill part or all of a shore pine
needle. The needle reddens and dies, or portions
of the needle die, depending on how much salt is
deposited. This can give the tree crowns a singed
or scorched look, which may appear only on the
windward side of the crown (figure 7). There is
a clear landscape effect, with trees in exposed
windward hillsides overlooking the ocean often
getting the full brunt of the salt spray, with the
occasional more inland hilltop getting hit also.
Figure 7. Shore pine with salt damage.
(Photo by Alan Kanaskie, Oregon Department of Forestry, used by
permission.)
Shade
Shore pine is a sun-loving tree that can tolerate
Oregon’s coastal rainfall and drizzle patterns. It
requires full sun for best health and vigor. Crowding
and shading will impair tree vigor and result in
spindly and poorly growing trees with poor foliage
retention (figure 8). Some trees growing in deeper
shade may look thin-crowned, have foliage disease
or insect scales on old needles, and have thin spindly
branches with small tufts of foliage at the ends. If
trees are left in this condition for a long time, they
may not respond well if they are suddenly exposed
when competing vegetation is removed.
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Figure 9. A purchased shore pine that died recently after
planting, near Newport, Oregon.
Figure 8. Shore pine growing in shady spot, with poor
foliage retention. Note also that the tree is in a canopy gap
where humid air pools and foliage diseases and gall rust
might be enhanced.
Overwatering
A shore pine growing on a lawn is best left
unwatered, even in our sandy soils, except in the
initial planting. Shore pine is adapted to the summer
and fall drought that occurs most years along
Oregon’s coast. Tree roots develop poorly if the tree
is overwatered. Root diseases such as the exotic
water mold Phytophthora cinnamomi and other
Phytophthora species can cause disease in the well-
watered landscape, whereas they are rarely a concern
in the natural stands. Armillaria root disease can
also impact trees not used to well-watered roots.
Therefore, a tree growing in a watered lawn that
dies for no apparent reason may have been killed by
the invisible action of below-ground agents that are
difficult to detect after the tree has died.
Potted trees
Trees grown in pots can have very constricted
and bound roots, especially if the tree has been in
the pot too long. If you buy a tree that is in a pot
and you pop it out of the pot and plug it into a hole
in the ground, the tree may not thrive. Perhaps it
will remain there for a few months or even a few
years, and then die (figure 9). Another possibility
is that the tree will grow roots out of the bind and
recover to grow into a nice shade tree. Often times a
portion of the crown may die because of poor root
development, but the whole tree does not.
Inspect the root ball of a tree before buying it
to determine if it has severe root binding. If you
purchase a tree, you should know if it has been
potted for too long. When planting a potted tree,
break up the root ball and don’t allow it to retain the
shape of the pot so that the tree can grow roots out
into the surrounding soil.
Trenching/construction damage
The architecture of a given tree is a balance
between the crown and the roots. The size of the
crown is related to the size of the root system. Each
individual leaf has a direct connection to certain
roots due to small capillary water streams. Although
trees have some ability to compensate when a major
portion of the root system is severed, the crown
cannot be sustained, and a portion of the leaves and
branches are shed (die). Butt wounding and root
damage, especially severed roots from trenching,
can cause a tree to die or to lose some portion of
the crown to what appears as drought damage.
Wounding also allows access to root diseases and
wood rots and encourages bark beetles such as the
red turpentine beetle, which further weakens the
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tree. Therefore, trenching and construction damage
are major concerns to existing trees in the landscape
and housing areas. Expect damaged trees to have a
wide range of health problems.
Windthrow
Windthrow of shore pine can occur during violent
windstorms, which often strike the coast of Oregon.
A recent example is the November 2007 storm along
the north coast. Although this is not often confused
with insect damage, heavily broken trees are often
attacked by red turpentine beetle. These beetles
cause pitch masses (1/2–1 inches across (1 – 3 cm))
to form at the base of the tree, where the beetles
enter the inner bark, lay eggs, and feed on cambium.
How this influences overall tree vigor is not well
quantified, as it is thought that a healthy tree can
tolerate red turpentine beetle and that these beetles
rarely kill a tree. However, for crown-damaged trees,
an additional assault on individual tree resources
may further reduce their vigor and the tree may die.
Pruning
Injured trees are more susceptible to insect attack.
Injury can either be naturally occurring, such as
by windstorms or ice breakage, or human-induced,
such as by pruning or breaking of limbs or rupturing
the bark on the trunk. Injured trees release volatile
compounds that attract insects by showing that the
tree’s defenses are weakened. To minimize insect
attacks, do not prune shore pine in the spring or
summer. Pruning should be done between October
and February. Particular attention should be paid to
proper pruning; do not damage the branch collar,
because this will attract pitch moths.
Off-site plantings
Trees that are not genetically suited to an area
are called off-site. Off-site plantings are often more
susceptible to insect attacks. So, if you plant a shore
pine, make sure that the tree was grown from local
seed sources; i.e., it is a shore pine and not a lodgepole
pine from eastern Oregon or the Rocky Mountains.
A. Bark beetles, ambrosia beetles, and wood borers.
Species Notes Symptoms Signs
Red turpentine beetle
Dendroctonus valens
Rarely kills trees Pitch mass at base of tree, up to ~5 ft.
Can be small reddish pitch outs.
Adult beetles red-brown, 3/8 in
long. Grubs feed gregariously.
Pine engraver beetles
Ips species
Pseudips mexicanus
(Monterey pine engraver)
Can kill tops, branches, and whole trees. Usually
invades recent dead tree.
Red boring dust. Pitch out. Red foliage. Adult beetles 1/8–3/16 in long.
White grubs at bark/wood
interface.
Shore pine bark beetle
Pseudohylesinus pini
Known from branches and upper bole of weakened
and dying trees.
Red boring dust. Adult beetles ~ 1/8 in long. White
gurbs at bark/wood interface.
Dendroctonus ponderosae
(Mt. Pine beetle)
The Mt. Pine beetle, which is killing billions of lodgepole
pine trees in western North America, is not present on
the coast, although there have been rare reports of
outbreaks associated with imported fresh firewood.
Ambrosia beetles
Several species
Does not kill trees. Invades recent dead tree. White boring dust outside bark. Pinholes
in wood with associated stain.
Adult beetles 1/64–1/8 in long.
White grubs in “cradles” in wood.
Wood borers
Several species
Monochamus maculosus
(spotted pine sawyer)
Colonizes dead trees. Not a tree killer. Boring throughout dead wood.
Wandering galleries at bark and wood
interface.
Adult beetles and larvae can be
large, >1.5 in.
Major Insect Problems of Shore Pine (see table 2)
Table 2. Potential insect pests of shore pine. Many of these insects are known pests of lodgepole pine and therefore could
influence shore pine. Documentation of shore pine pests is lacking, perhaps due to the low number of pests along the
coast. Symptoms are the visible response of the plant (red foliage, resin flow, reduced growth, and wilting). Signs are the
physical presence of causal agents (beetle grub or fungal fruiting body).
There are few major insect problems of shore pine;
the sequoia pitch moth is perhaps the most common.
We discuss insects that could damage the tree, based
on our local knowledge and their importance in other
lodgepole systems. This discussion follows the listing
in table 2 and begins with beetles.
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B. Defoliators.
Species Notes Symptoms Signs
Silver spotted tiger moth
Lophocampa argentata
Abundance varies year to year.
Rarely harms trees, but can be
unsightly.
Localized defoliation of older needles in
winter and spring. Webbing and red foliage
hang on tre
