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Kingdom: Plantae
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Figure 1: Maple Tree |
Geography 316: Biogeography
Biogeography of Bigleaf Maple (Acer macrophyllum)
by
Alicia Mariscal, student in Geography 316, Fall 2001
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Kingdom: Plantae
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Figure 1: Maple Tree |
Description of Species |
Habitat |
Natural History |
Evolution |
Distribution |
Other Interesting Issues |
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The
bigleaf maple is a commercial hardwood, small to medium sized tree on the
Pacific Coast. It grows from 25 to 100 feet tall and 1 to 9 feet in
diameter. These larger size dimensions occur when it grows in the rich,
alluvial river bottomlands (Sudworth 1908). It is also found in mountain
valleys, as the border of low mountain streams and foothill areas; and on
rocky slopes (Harlow et al.
1979; Peattie 1991). The bigleaf maples’ name derived from foliar
attributes, mature leaves are from 7 to 14 inches in diameter (van
Gelderen et al. 1994); deeply
5-lobed; and shiny on top with a glabrous (smooth, not hairy) surface,
paler green underneath (Sargent 1905; Sudworth 1908).
The
leaves turn a clear, reddish yellow just before falling. The leave stems
are from 6 to 12 inches long. When the tree
is about twenty years old and the leaves are grown for that season,
drooping clusters of fragrant yellow flowers (a polygamous species)
appear. The flowers are about 1/4 inch long
on a stalk that is about 1/2-3/4 inch long; these together form racemes 4
to 6 inches long (Sargent 1905; van Gelderen et
al. 1994). |
| Figure 2: Maple Leaf (TreeGuide Inc. 2001) |
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These flowers produce the trees’ tawny or yellowish brown fruit, their seeds (Figure 3), which in large quantities appear in autumn. The seeds usually remain on the branches until winter or longer. This tree is deciduous and sheds all of its leaves (Peattie 1991). The wings of the seeds, or samaras, are slightly divergent and about 1˝ inches long (Crittenden 1997). The outer portion of the seed is covered with stout and sharp pale brown hair (Sudworth 1908). The wings spread out at <90° angle (Hickman, 1993). |
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bark of bigleaf maples is checkered or with narrow grooves (Crittenden 1997).
Characteristic of old trunks are rough bark with pale gray to reddish-brown
colored hard, scaly ridges. The wood is finely grained and hard, with a light
brown color and a very light reddish tint (Sudworth 1908). Large burls
occasionally develop along the boles of older trees, which are frequently
defective (Harlow et al. 1979). |
Figure
3: Maple Seed |
In
dense forest conditions it develops a narrow crown, and a bole (or stem of the
tree) usually without limbs for a half to two-thirds of its height (Preston
1976). When the tree grows in an open area the short tree trunk generally
separates into several ascending, stout branches that form a compact ovate to
subglobose crown (Sudworth 1908). In all of its habitats it has a shallow and
far-reaching root system (Preston 1976).
A.
macrophyllum has
been identified for 200 years (van Gelderen et
al. 1994). The first scientist to collect specimens of this tree was
Archibald Menzies, a botanist with the Vancouver Expedition. The first Americans
to collect specimens were Lewis and Clark. Thomas Nuttall, a botany professor at
Harvard provided us with the first visual illustration and written description
of the bigleaf maple in his work, The
North American Sylva. Pursh wrote a full description of the tree in 1814
(van Gelderen et al. 1994). This tree
also grows in England, its seeds brought over by David Douglas (Peattie 1991).
Habitat:
The bigleaf
maple is the largest maple tree in the Pacific region (Sudworth 1908). It is
also called broadleaf, Oregon, Canyon, or White maple (Crittenden 1997; Peattie
1991).
This
tree is found primarily in cool habitats (Crittenden 1997). The bigleaf maple
grows on a variety of soils, but usually it is found in rich humus soils that
are moist and gravelly (Sudworth 1908). Frequent fires (Rundel & Parsons
1977) aid the growth of the trees in these areas.
The maple is also the principal forest species in areas where the land is burned or logged, such as in some sections of southwestern Oregon (Harlow et al. 1979).
The
trees grow in dense stands over large areas of land, in small groves, or
scattered. It is usually found in proximity to other evergreen broad-leaved
species or coniferous trees, such as lowland Douglas firs, red alder, Pacific
madrone, cypress, California redwood, and California laurel (Axelrod 1977;
Harlow et al. 1979; Sudworth 1908).
Natural History:
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The bigleaf maple
tree begins to flower (Figure 4) at about twenty years of age. Insects and bees pollinate
the tree and produce about 1000 pollen grains (55µm each) for an individual flower. This is a low number of pollen grains
when compared to wind-pollinated oaks, birches, ashes, poplars, and elms that
produce about 10,000 pollen grains per flower. Characteristic of the Acer
genus to have a low pollen yield, it is one reason why microfossils of Acer
pollen are infrequently found (van Gelderen et
al. 1994). This
tree effectively naturally regenerates each year, due to the abundance of seed
it produces, especially in the open areas. Stump sprouts are full of vitality
(Harlow et al. 1979). The bigleaf maple grows the most during its first forty- to sixty years, after which time growth decreases considerably. A mature tree is between two and three hundred years old. The forest trees live a range of fifty to eighty-five years (Sudworth 1908). |
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Figure 4: Maple Tree Flower |
Evolution:
An angiosperm, the
earliest known Acer (A.
amboyense) was found in eastern North America from the fossil remains of the
late Cretaceous period about 67 MYA. All maple fossils have been
located exclusively in the Northern Hemisphere and the trees seem most abundant
during the Miocene (Oterdoom 1994).
The
closest fossil relative to A. macrophyllum
appears to be A. merriamii Knowlton
(or A. oregonianum Knowlton) from the
Late Miocene around 5 MYA (Macginitie 1969; Oliver 1934). Macginitie (1969)
notes the potential for a taxonomic problem with assigning the name of a fossil
species to a living species, for although they may be morphologically similar it
is difficult to determine if the species are genetically identical.
The
flowering and sexual mating of Acer have
ranged from wind-pollinated to insect-pollinated and monoecy to dioecy.
A.
macrophyllum
is an insect-pollinated dicot in which
female flowers occur before male flowers (Oterdoom
1994).
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The
form of the leaves in the Acer genus
has changed over time. From the Late Oligocene to the Early Pliocene (from
around 23 to 5 MYA, including the Miocene) the leaf form evolved from the
originally more common 3-lobed maples to 5-lobed maples, as evidenced in the
paleobotanical studies of the broadening of the A. tricuspidatum leaf base (Oterdoom 1994). A.
macrophyllum
belongs to the deciduous maple Aceraceae family, which has 200 species
distributed among 2 genera (van Gelderen et
al. 1994). Acer species is
believed to have originated in central and western China although no fossils
have been located in this area (Oterdoom 1994). Cladistic analysis
has concluded that the Aceraceae family was formed by earlier members of the
Sapindaceae like Bohlenia, which was characterized by loss of a stipule and a
locule, as well as a change to opposite from alternate leaves. The Dipteronia
line of the Aceraceae seems to be more closely related to the Sapindaceae
ancestor Bohlenia, except for a change in the secondary venation of its
pinnately compound leaves. The A. arcticum
line resulted in an actinodromous maple leaf after the fusion of a minimum
of three leaflets (Stewart & Rothwell 1993; van Gelderen et
al. 1994). |
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Figure
5 illustrates the phylogeny of the Acer genus divided into five
groups, relating them to Acer’s most prehistoric ancestor (de
Jong 1994). |
Figure 5: Maple Evolutionary Tree (de Jong 1994) |
Distribution:
Figure 6 highlights
thirty-seven counties in California that contain native groves of the bigleaf
maple within them. A. macrophyllum has
a continuous distribution on the Pacific coast of California, and is native to
the west coast of North America (Harlow et
al. 1979).
Fossil
records reveal that the bigleaf maple is a descendant to the associates of the
Miocene floras of the central Great Basin (Axelrod 1977). It is also a member of
the Blue Mountains flora in Oregon. It has been found in the Miocene of western
Nevada. This tree is a contributor to the San Francisco Bay region savanna and
oak woodland sites. In southern Humboldt County it was seen as a riparian
species in the forest. It has been located on the mesic slopes of the Shasta fir
closed forests; and six small to medium-sized stands of the bigleaf maple are on
the northern portion of Santa Cruz Island.
The
maple tree is found in numerous locations in the western states, as illustrated
in Figure 7. Among these
include the area south of 55şN latitude on the coast of Alaska (Sargent 1905;
Sudworth 1908); in British Columbia and its islands up to 1,000 feet above sea
level (Crittenden 1997; Harlow et al.
1979); west of the Cascade Mountains in Washington and Oregon (Peattie 1991);
and throughout California, especially the Coast Ranges and Sierra, and including
areas from 3,000 to 7,000 feet in Southern California (Crittenden 1997; Harlow et
al. 1979).
Maps of Distribution:
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Figure
6: Map of bigleaf maple tree distribution in California |
Figure 7: Map of bigleaf maple tree distribution in North America (TreeGuide Inc. 2001) |
Other Interesting
Issues:
A.
macrophyllum is
a shade tree, mostly because of its very long and broad leaves. Since it is
lobed it allows some light to pass through. A walk through a mixed evergreen or
conifer forest would find these trees growing in the light gaps of the forest.
The light yielded through this tree when its reddish yellow leaves are just
about to fall is spectacular. My favorite place locally where this occurs is in
Muir Woods National Monument in Marin County, California.
Pseudomonas
acris, a
bacterial agent, sometimes causes a leaf spot on the leaves of this tree in
California. An aphid, Drepanosiphum
oregonensis, was first discovered on this tree in North America. Unknown
until its discovery on the bigleaf maple, this aphid is native to the eastern
Mediterranean (van Gelderen et al. 1994).
The
commercialization of this species has increased due to the demand for western
maple burls and fancy grained logs. It is one of the main hardwood lumbers of
the west, and is used for similar purposes as the eastern maple. The main uses
of the wood are for furniture, flooring, interior veneers, and boat building (Peattie
1991; Preston 1979). In the past it has also been used for making gun stocks,
canoe paddles, and sugar made from its sap (Peattie 1991).
The
bigleaf maple has only four known rare cultivars which are only occasionally, if
still, available: ‘Kimballiae’ and ‘Seattle Sentinel’ from Washington,
‘Rubrum’ from the U.C. Berkeley Blake Gardens, and ‘Tricolor’ from
Germany which is no longer in cultivation (van Gelderen et al. 1994).
Interesting
Websites:
CalFlora:
Information on California plants for education, research and conservation. 2000.
Acer
California: The CalFlora Database
Fire Effects
Information Service. 2001. Index of Species Information. Species: Acer macrophyllum. [Online].
Available: http://www.fs.fed.us/database/feis/plants/tree/acemac/
Government of
British Columbia, Ministry of Forests. 2001. Treebook: Bigleaf Maple. [Online].
Available:
National Park
Service. 2001. The Bigleaf Maples of English Camp. [Online]. Available: http://www.nps.gov/sajh/maple.htm
Phommosaysy, Chan.
2001. CSU Fullerton, Biological Sciences. Bigleaf Maple – Acer
Available:
http://biology.fullerton.edu/courses/biol_445/Web/blmaple.htm
TreeGuide
Inc. 2001.
Bigleaf Maple: Acer Macrophyllum Pursh.
[Online].
Available:
http://www.treeguide.com/Species.asp?SpeciesID=87&Region=NorthAmerican
Puget Sound Shorelines, Washington State Department of Ecology. 2001.
Bigleaf Maple – Acer
Available:
http://www.ecy.wa.gov/programs/sea/pugetsound/species/maple.html
Bibliography
Axelrod, D.I. 1977. Outline History of California Vegetation. In Terrestrial
Vegetation of
New York: John Wiley & Sons.
©
Brousseau, Br. A., Saint Mary's College. 1995. CalFlora:
Information on California plants for education, research and conservation. 2000.
Berkeley, California: The CalFlora Database [a non-profit
organization]. [Online]. Available: http://www.calflora.org/.
[September
27, 2001]
CalFlora:
Information on California plants for education, research and conservation. 2000.
Berkeley, California: The CalFlora Database [a non-
profit
organization]. [Online]. Available:
http://www.calflora.org/.
[September 27,
2001]
Crittenden, M. 1997. Trees of the West. Millbrae: Celestial Arts.
de Jong, P.C. 1994. Taxonomy and
Reproductive Biology of Maples. In Maples of the World, eds.
D.M. van Gelderen, P.C. de Jong, and H.J.
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Harlow, W.M., E.S. Harrar, and F.M. White, eds. 1979. Textbook of Dendrology. San Francisco: McGraw-Hill Book Company.
Hickman, J.C., ed. 1993. The Jepson Manual: Higher Plants of California. Berkeley: University of California Press.
Macginitie, H.D. 1969. The
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Through
Pliocene, eds. T.N. Taylor and E.L.
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McClellan, J.E., and B. McClellan, California Academy of Sciences. 1999. Maple Tree. CalFlora:
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research and conservation. 2000.
Berkeley, California: The CalFlora Database [a non-profit
organization]. [Online]. Available:
http://www.calflora.org/.
[September 27,
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Mountains, Oregon. In Contributions to
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Peattie, C.D. 1991. A Natural History of Western Trees. Boston: Houghton Mifflin Company.
Preston
Jr., R.J. 1976. North American Trees –
Third Edition. Ames: The Iowa State University
Press.
Puget Sound
Shorelines, Washington State Department of Ecology. 2001. Bigleaf Maple – Acer
Available:
http://www.ecy.wa.gov/programs/sea/pugetsound/species/maple.html
[Permission Granted October 31, 2001].
Rundel, P.W.,
and D.J. Parsons. 1977. Montane and Subalpine Vegetation of the Sierra
Nevada and Cascade Ranges. In Terrestrial
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of
California, eds. M.G. Barbour, and J.
Major, 565. New York: John Wiley & Sons.
Sargent, C.S. 1905. Manual of the Trees of North America. Cambridge: The Riverside Press.
Stewart,
W.N., and G.W. Rothwell. 1993. Paleobotany and the Evolution of Plants – Second
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Sudworth, G.B. 1908. Forest Trees of the Pacific Slope. Washington: U.S. Government Printing Office.
TreeGuide
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Bigleaf Maple: Acer Macrophyllum Pursh.
[Online]. Available:
http://www.treeguide.com/Species.asp?SpeciesID=87&Region=NorthAmerican [Permission Granted October 23, 2001].
van Gelderen, D.M., P.C. de Jong, and H.J. Oterdoom. 1994. Maples of the World. Portland: Timber Press, Inc.
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