Pine family (Pinaceae)
This coniferous tree is 30–80' tall at maturity, and the trunk of a
mature tree is ¾–2' across and straight. The crown of this tree is
narrowly conical and relatively open, while the trunk below the crown
is naked for about one-third to two-thirds of the tree's length as a
result of self-pruning. The
primary branches, originating from the trunk, are slightly ascending
above, widely spreading in the middle, and slightly drooping below.
There are also shorter twigs that originate from the primary branches.
Outer trunk bark of older trees is gray and somewhat scaly, while outer
trunk bark of young trees is gray and smooth. The outer bark of larger
branches is gray and relatively smooth, while twigs are brown, grayish
brown, or reddish brown. When the outer bark breaks away on
the trunk and larger branches, patches of reddish inner bark may become
visible. Tufts of 10-20 needle-like leaves develop on short spur-shoots
(about 3 mm. long) of the twigs. These leaves are ¾–1" (2–2.5 cm.)
long, about 0.5
mm. across, light to medium green, linear in shape, hairless, and
deciduous; they become yellow during autumn before they fall to the
Because Tamarack (Larix laricina) is monoecious, both male
flowers and female flowers develop on the same tree. The male flowers
develop from the tips of twigs, where they resemble clusters of yellow
buds. The female flowers develop near the spur-shoots of twigs on short
curved peduncles (up to 5 mm. long); they develop on immature scaly
cones that are reddish purple and less than ½" (12 mm.) in length. The
flowers are cross-pollinated by the wind during early to mid-spring.
Afterwards, the female cones continue to develop, becoming mature
during the late summer or early autumn of the second year. Mature cones
are ½–¾" (12–20 mm.) long, broadly
ovoid in shape, and brown to reddish brown. Each cone has 10-20
spirally arranged scales that are overlapping. The scales are
ovate-orbicular in shape and either smooth, slightly undulate, or
slightly lacerated along their upper margins. At the base of scale,
there are 2 winged seeds. The seed body is about 2-3 mm. in length,
while its wing is about 4-6 mm. long. The winged seeds are distributed
by the wind. The woody root system is very shallow (up to 2' deep) and
widely spreading. This tree reproduces primarily by reseeding itself,
although it can also reproduce by layering when its lower branches
touch moist ground.
The preference is full sun, wet conditions (but not flooded), an
acidic peaty soil, and cool climate. However, moist sites with
more mineral-rich soil are tolerated as well. This tree can be
propagated from either seeds or cuttings. It can live for
150-200 years (rarely longer), and seed cones may be produced in as
little as 15-30 years.
Habitat: The native Tamarack (Larix laricina)
is rare, occurring only in the NE corner of the state; it is
state-listed as 'threatened' (see Distribution
Map). Illinois lies along the southern
range-limit of this tree; it is more common further to the north.
Tamarack occurs primarily in the Great Lakes region,
northeastern United States, and boreal areas of Canada. The primary
habitat consists of forested or shrubby bogs where sphagnum mosses are
often present on the ground. Less commonly, Tamarack occurs in less
acidic wetlands, such as forested fens. In forested bogs, Tamarack is
often codominant with Black Spruce (Picea
mariana). Because of its
shallow roots and thin bark, this tree is easily damaged by wildfires.
In Illinois, it is found in high quality natural areas.
Associations: Many insects feed on the needle-like leaves,
and other parts of Tamarack (Larix
laricina) and other larches (Larix
spp.). These insect feeders include woolly conifer aphids (Adelges
spp.), giant conifer aphids (Cinara spp.), plant
bugs (Miridae), adults
of some spittlebugs (Aphrophora
spp.), larvae of Pristiphora
(Larch Sawfly), larvae of Urocerus albicornis (White-horned
Horntail), larvae of various long-horned beetles and bark beetles
(Cerambycidae, Scolytidae), and larvae of Coleophora laricella (Larch
Casebearer Moth), Tolype
laricis (Larch Lappet Moth), and other moths.
Another insect that is found on Tamarack is the Larch Tree Cricket
See the Insect Table for a
more complete listing
of these species. Vertebrate animals also use larches as a source of
food and for other purposes. The seeds of Tamarack are eaten by the Red
Crossbill, Pine Siskin, and other birds (see the Bird Table
information). Some birds, like the Blue Jay, Bald Eagle, and Osprey,
use larches as nesting sites (DeGraaf, 2002; Uchytil, 1991). The seeds
of this tree are also eaten by the Red Squirrel, mice, voles, and
shrews (Uchytil, 1991). White-tailed Deer feed sparingly on the twigs
and young shoots, while the Porcupine feeds on the inner bark.
Volo Bog in Lake County, Illinois.
Tamarack (Larix laricina)
is one of the few trees that flourishes in
bogs. Because this tree has a relatively open crown that produces only
light shade, shrubs are usually abundant in Tamarack-dominated bogs.
Tamarack is unusual for a coniferous tree because it sheds its leaves,
becoming leafless during the winter. This reduces its ability to
provide protective cover for wildlife during the winter. A similar
species, Larix decidua (European
Larch), is cultivated as a landscape
plant, although this is rather uncommon. It has been known to escape
from cultivation and naturalize in Illinois on rare occasions. This
latter tree can be distinguished from Tamarack by its longer seed cones
(¾–1½" in length) that have more numerous scales; these scales are
hairy when they are young. The leaves of this tree are also slightly
longer in length (up to 1¼"), and it adapts to drier situations. There
are additional larch species (Larix
spp.) in western North America, but
they also have larger seed cones with more numerous scales. Another
common name of Larix
laricina is American Larch.