Species of conifer
The
western larch
(
Larix occidentalis
) is a species of
larch
native to the mountains of western
North America
(
Pacific Northwest
,
Inland Northwest
); in
Canada
in southeastern
British Columbia
and southwestern
Alberta
, and in the
United States
in eastern
Washington
, eastern
Oregon
, northern
Idaho
, and western
Montana
. It is the most productive of the three species of larch native to North America.
[2]
[3]
Description
[
edit
]
The tree is a large
deciduous
conifer
reaching 30 to 60 meters (98 to 197 feet) tall, with a trunk up to 1.5 m (4 ft 11 in) diameter; the bark ranges from orangish to purplish brown.
[4]
The crown is narrow conic; the main branches are level to upswept, with the side branches often drooping. The shoots are dimorphic, with growth divided into long shoots (typically 10 to 50 centimeters (4 to 20 in) long) and bearing several
buds
, and short shoots only
1 to 2 millimeters (
1
⁄
32
to
3
⁄
32
in) long with only a single bud. The
leaves
are needle-like, light green,
2 to 5 cm (
3
⁄
4
to 2 in) long, soft
[4]
and very slender; they turn bright yellow in the fall, leaving the pale orange-brown shoots bare until the next spring.
[5]
The seed
cones
are ovoid-cylindric,
2 to 5 cm (
3
⁄
4
to 2 in) long, with 40 to 80 seed scales; each scale bearing an
exserted
4 to 8 mm (
3
⁄
16
to
5
⁄
16
in)
bract
. The cones are green
[4]
to reddish purple when immature, turning brown and the scales opening flat or reflexed to release the
seeds
when mature, four to six months after pollination. The old cones commonly remain on the tree for many years, turning dull gray-black.
[5]
Individual specimens can live centuries, even up to a millennium.
[4]
The largest known specimen is about 1,000 years old, 50 m (160 ft) tall and over 2 m (7 ft) in diameter with a 10 m (34 ft) crown, located at
Seeley Lake, Montana
.
[4]
[5]
Distribution
[
edit
]
Western larch grows almost exclusively in the drainage of the
Columbia River
, from the east of the
Cascade Range
to the west of the
Continental Divide
.
[4]
It covers the regions from around
Kamloops
,
British Columbia
, to
Weiser, Idaho
, and
Central Oregon
.
[4]
It appears on ranges including the
Blue Mountains
and others in southeast BC and northwest
Montana
, usually on moist slopes up to 1,800 m (5,900 ft) above sea level.
[4]
It can grow from elevations between 500 and 2,400 m (1,600 and 7,900 ft) and is very cold tolerant, able to survive winter temperatures down to about ?50 °C (?58 °F). It only grows on well-drained soils, unable to thrive on waterlogged ground.
[6]
Ecology
[
edit
]
Western larch grows more quickly than many associated trees, as it needs to because larch is
shade intolerant
. With its thick bark, nonflammable foliage and protective cones, the species is very
fire resistant
.
[4]
In the late 20th century, after wildfires had been suppressed for almost a century, larches at Seeley Lake and
Glacier National Park
were endangered by major fires enabled by
fuel ladder
; normally smaller fires would have depleted the fuel.
[4]
In more recent years, many smaller fires have been allowed to take their course.
[4]
Grouse browse the tree's leaves and buds.
[7]
The seeds are an important substitute winter food for some birds, notably the
pine siskin
but also the
redpoll
, and
white-winged crossbill
. This is frequently during times when other conifer cones that are a more preferred diet are in short supply.
[8]
[9]
[10]
Woodpeckers utilize the
heart rot
of older specimens to make openings, which are used by various small animals.
[4]
Assisted migration
[
edit
]
In 2010, the
Government of British Columbia
implemented an
assisted migration
program of western larch to a new habitat in northern British Columbia, about 1000 kilometers north of its current range.
[11]
Assisted migration of
Canadian forests
had been proposed as an adaptation measure in response to
climate change
. Indeed, as average temperatures rise, the optimal climate conditions for trees species are also moving North. Research had shown that western larch trees have no trouble growing in northern BC, an area whose climatic conditions are predicted to match the western larch's historical range by 2030.
[3]
British Columbia started seeding western larch trees in northern BC in the early 2010s. This was the first assisted migration program for a North American tree. The western larch was selected for because of its significant commercial importance and the fear that
climate change
and parasites such as the
mountain pine beetle
would considerably diminish its supply. To pre-empt opposition from biologists and other groups, the government avoided making public consultation on the program. Instead, they framed the policy as an introduction of a non-exotic species to a similar environment, and implemented the program through the province's existing legal and regulatory framework.
[3]
Foresters in the United States have also initiated "experimental treatments" of larch-dominated national forests in Montana.
[12]
However, if some "aggressively warming climate scenarios" actually unfold, foresters will need to let go of any expectations of helping this species maintain a presence south of the Canadian border.
[13]
Uses
[
edit
]
Indigenous peoples applied the resinous gum to injuries and chewed it to treat sore throat.
[4]
Some also ate the
cambium
and sap;
[14]
the
Kutenai
and
Salish peoples
of Montana in particular collected the sap.
[4]
A medicinal tea was made from the bark or foliage.
[4]
Some
Plateau Indian
tribes drank an infusion from the young shoots to treat
tuberculosis
and
laryngitis
.
[15]
The sweetish
galactan
of the sap can be made into baking powder and medicine.
[7]
An extract of the tree is sold as a health supplement.
[4]
The water-soluble
arabinogalactan
is used in food, medicine, ink, and paint.
[4]
The
wood
is tough and durable, but also flexible in thin strips, and is particularly valued for
yacht
building; wood used for this must be free of knots, and can only be obtained from old trees that were
pruned
when young to remove side branches. Small larch poles are widely used for rustic fencing.
[16]
The wood is highly prized as
firewood
in the
Pacific Northwest
where it is often called "tamarack," although it is a different species than the
tamarack larch
. The wood burns with a sweet fragrance and a distinctive popping noise.
[17]
Western larch is used for the production of
Venice turpentine
.
[18]
Gallery
[
edit
]
-
Western larch in autumn
-
Leaves and mature cones
-
Larix occidentalis
-
Young cones
References
[
edit
]
- ^
Farjon, A. (2013).
"
Larix occidentalis
"
.
IUCN Red List of Threatened Species
.
2013
: e.T42315A2971858.
doi
:
10.2305/IUCN.UK.2013-1.RLTS.T42315A2971858.en
. Retrieved
November 19,
2021
.
- ^
Rehfeldt, Gerald E.; Jaquish, Barry C. (March 2010).
"Ecological impacts and management strategies for western larch in the face of climate-change"
.
Mitigation and Adaptation Strategies for Global Change
.
15
(3): 283?306.
doi
:
10.1007/s11027-010-9217-2
.
ISSN
1381-2386
.
S2CID
154285038
.
- ^
a
b
c
Klenk, Nicole L. (March 1, 2015).
"The development of assisted migration policy in Canada: An analysis of the politics of composing future forests"
.
Land Use Policy
.
44
: 101?109.
doi
:
10.1016/j.landusepol.2014.12.003
.
ISSN
0264-8377
.
- ^
a
b
c
d
e
f
g
h
i
j
k
l
m
n
o
p
q
Arno, Stephen F.; Hammerly, Ramona P. (2020) [1977].
Northwest Trees: Identifying & Understanding the Region's Native Trees
(field guide ed.). Seattle:
Mountaineers Books
. pp. 70?76.
ISBN
978-1-68051-329-5
.
OCLC
1141235469
.
- ^
a
b
c
"Larix occidentalis"
.
Gymnosperm Database
. February 26, 2004. Archived from
the original
on March 14, 2006
. Retrieved
February 3,
2022
.
- ^
Lowery, David P. (February 27, 1985).
"Western Larch (Larix occidentalis Nutt.): An American Wood"
(pdf)
.
Fs-243
.
243
. Missoula, MT:
USFS
: Forestry Sciences Laboratory – via
USDA
.
- ^
a
b
Whitney, Stephen (1985).
Western Forests (The Audubon Society Nature Guides)
. New York: Knopf. p.
363
.
ISBN
0-394-73127-1
.
- ^
"Pine Siskin: Life History"
.
allaboutbirds.org
. Retrieved
February 24,
2021
.
- ^
"Common Redpoll: Life History"
.
allaboutbirds.org
. Retrieved
February 24,
2021
.
- ^
"White-winged Crossbill: Life History"
.
allaboutbirds.org
. Retrieved
February 24,
2021
.
- ^
Buranyi, Stephen (January 20, 2016).
"How British Columbia Is Moving its Trees"
.
motherboard.com
. Vice Media Inc. Archived from
the original
on April 29, 2016
. Retrieved
February 20,
2021
.
- ^
Crotteau, Justin S (August 2019).
"Initiating Climate Adaptation in a Western Larch Forest"
(PDF)
.
Forest Science
.
65
(4): 528?536.
doi
:
10.1093/forsci/fxz024
.
- ^
Rehfeldt, Gerald E.; Jaquish, Barry C. (March 2010).
"Ecological impacts and management strategies for western larch in the face of climate-change"
.
Mitigation and Adaptation Strategies for Global Change
.
15
(3): 283?306.
doi
:
10.1007/s11027-010-9217-2
.
ISSN
1381-2386
.
S2CID
154285038
.
- ^
Turner, Nancy J.
Food Plants of Interior First Peoples
(Victoria: UBC Press, 1997)
ISBN
0-7748-0606-0
- ^
Hunn, Eugene S. (1990).
Nch'i-Wana, "The Big River": Mid-Columbia Indians and Their Land
.
University of Washington Press
. p. 354.
ISBN
0-295-97119-3
.
- ^
"Fence Post 101: Start with a Good Fencing Foundation"
.
zarebasystems.com
. Woodstream Corporation
. Retrieved
February 26,
2021
.
- ^
"Larch Firewood"
.
firewood-for-life.com
. Retrieved
February 26,
2021
.
- ^
"Turpentine Oil | Applications and Specifications"
.
turpentine-oil.com
. Retrieved
February 23,
2021
.
External links
[
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]