Populus tremuloides Michx. - Quaking Aspen
Native , Common
By Steven D. Glenn
Not peer reviewed
Last Modified 03/11/2013
Common NamesQuaking Aspen
Food usesDisclaimer: The information provided here is for reference and historical use. We do not recommend nor do we condone the use of this species for food purposes without first consulting a physician.
Inner bark used by Native Americans for food. Wood used to cure fish and meat. Moerman, 1998
Medicinal usesDisclaimer: The information provided here is for reference and historical use. We do not recommend nor do we condone the use of this species for medicinal purposes without first consulting a physician.
Used by Native Americans for joint pain, heartburn and stomach pain, wound dressing, colds, bed-wetting, veneral disease, deodorant, coughs, and for those "suffering from insanity through excessive drinking". Also used as a protective bath against witches. Moerman, 1998
Other usesUsed by Native Americans for builing material for lodges, dugout canoes, toy whistles, cups, and hats. Moerman, 1998
Populus tremuloides Michx., Fl. Bor. Am. 2: 243. 1803.
?Populus graeca G&D ex C.F. Ludwig., Neu. Wilde Baumz. 35. 1783.
?Populus atheniensis Lod. ex C.F. Ludwig., Neu. Wilde Baumz. 35. 1783.
Populus trepida Willd., Sp. Pl. 4,2: 803. 1806.
Populus laevigata Willd., Sp. Pl. 4,2: 803. 1806.
Populus cretica ex Dumont de Courset, Bot. Cult. ed. 2, 7: 343. 1814.
Populus benzoifera Tausch, Flora 21, 2: 754. 1838.
Populus tremuliformis Emerson, Tree Shrubs Mass. 243. 1846.
Populus tremuloides f. minor Cockerell, Nat. Notes 2: 14. 1891.
Populus tremuloides f. nana Cockerell, Bull. Torrey Bot. Club 18: 172. 1891.
Tremula trepida Raf. ex B.D. Jackson, Index Kew. 2: 1100. 1896.
Populus tremuloides var. sieboldi Schelle in Beissn., Schelle & Zabel, Handn. Laubholzben 14. 1903.
Populus cercidiphylla Britt., N. Amer. Trees 180, fig. 139. 1908.
Populus aurea Tidestrom, Amer. Midl. Nat. 2: 35. 1911.
Populus tremuloides var. davisiana Tidestr., Amer. Midl. Naturalist 2: 35, pl. 1, fig. 10. 1911.
Populus tremuloides var. reniformis Tidestr., Rhodora 16: 206. 1914.
Populus tremuloides var. cercidiphylla Sudw. in Sudw., Check List For. Trees U.S. 61. 1927.
Populus tremuloides var. intermedia Vict., Contr. Lab. Bot. Univ. Montreal no. 16: 8, fig. 2. 1930.
Populus tremuloides var. magnifica Vict., Contr. Lab. Bot. Univ. Montreal no. 16: 10, fig. 2. 1930.
Populus tremuloides var. rhomboidea Vict., Contr. Lab. Bot. Univ. Montreal no. 16: 10, fig. 2. 1930.
Populus tremuloides f. betuloides J.Rousseau, Bull Jard. Bot. Etat. 27: 377. 1957.
HABIT Perennial, deciduous, phanerophytic, tree, diclinous and dioecious; it is small- to medium-sized, typically less than 15 m in height and 40 cm dbh; but ranging up to 35 m tall and diameter of 1 m. It has spreading branches and a pyramidal or rounded crown.
STEMS Main stems erect, round. Bark smooth, light green to sometimes almost white, occasionally furrowed on the oldest specimens, not exfoliating. Bark remains smooth due to persistent periderm (Kaufert, 1937). For a hypothesis that the light-colored bark reduces the risk of winter sunscald injury, probably by protecting the cambium from solar heat gain in subfreezing temperatures see Karels, 2003. For a micro-anatomical study of bark and cambium see Davis & Evert, 1968. Branches erect or ascending. For a study of xylem vessel length see Zimmermann & Jeje, 1981. Twigs brown or light brown or gray or reddish-brown, not odoriferous, terete, 2-6 mm in diameter, smooth, glabrous. Pith brown, 5-pointed, continuous, nodal diaphragm absent. Sap translucent. Roots able to form ectomycorrhizal associations (Vozzo & Hacskaylo, 1974). For a synopsis of the root system see Stettler et al, 1996.
BUDS Terminal and axillary present, scattered along stem; terminal bud ovoid, pointed, viscid; axillary buds 1 per axil, ovoid, viscid. Bud scales dark brown to reddish-brown, imbricate, chartaceous, glabrous. Bud scale scars not encircling the stem. Leaf scars crescent-shaped. Vascular bundle scars 3, crescent-shaped.
LEAVES Alternate, simple, spaced somewhat evenly along and divergent from stem. Stipules lateral, free from the petiole, leaf-like, caducous. Leaves petiolate, petiole flattened, 2-7 cm long, glabrous. Leaf blades: abaxial surface light green, glabrous; adaxial surface green, glabrous, eglandular or occasionally with 1-2 sessile glands at petiole junction; elliptic or ovate or widely elliptic or widely ovate (some forms with extremely broad reniform or sub-orbicular leaves), bilaterally symmetric, 2-10 cm long, 2-9 cm wide, chartaceous, margin serrate, base cuneate to truncate or occasionally sub-cordate, apex acuminate or acute or apiculate or obtuse. Slightly heterophyllous, sometimes observed with leaves of the short shoots finely and regularly toothed; while leaves of the longer shoots with even smaller and more numerous teeth. For an overview of the micro-anatomy of the secondary leaf tissues see Stettler et al, 1996.
FEMALE INFLORESCENCES Precocious, formed on last season's growth, mostly unisexual (10-20% of predominately female trees bear perfect flowers (Fowells, 1965)(Howard, 1996), and some clones alternate between staminate and pistillate forms in different years, or produce various combinations of perfect, staminate, and pistillate flowers (Einspahr & Winton, 1977), axillary raceme, pendant, catkin-like. Usually with 70-100+ flowers. Peduncle and rachis moderately hairy. Bracts 1, subtending each flower, petiolate, adnate to pedicel, apices erose and ciliate, lateral surfaces glabrous. Pedicels 0.5-1.5 mm long, with short and unbranched erect or spreading white hairs, moderately dense, distributed throughout, not glabrescent.
FEMALE FLOWERS Perianth parts indistinguishable from one another, fragrance absent. Gynoecium set on perianth which is a crateriform disk composed of connate tepals (perigon). Perigon persistent, abaxial and adaxial surfaces light green, glabrous. Carpels 2. Locules 1. Style 1, short; stigmas 2, bifid. Ovary superior, ovoid, glabrous. Placentation parietal. For a review of the floral micro-anatomy and vascularization see Fisher, 1928. For a review of the floral micro-anatomy, vascularization and micro/mega-sporogenesis see Nagaraj, 1952.
MALE INFLORESCENCES Axillary raceme, with 8-100+ flowers, precocious, formed on last season's growth, mostly unisexual (4-5% of predominately male trees bear perfect flowers (Fowells, 1965)(Erlanson & Hermann, 1927) some clones alternate between staminate and pistillate forms in different years, or produce various combinations of perfect, staminate, and pistillate flowers (Einspahr & Winton, 1977)(Howard, 1996)), pendant; catkin-like. Peduncle and rachis moderately hairy. Bracts 1, subtending each flower, petiolate, adnate to pedicel, lateral surfaces brown, glabrous, apices erose and ciliate. Pedicels 1-2 mm long, sparsely beset with short and unbranched hairs.
MALE FLOWERS Perianth parts indistinguishable from one another, fragrance absent. Androecium set on perianth which is a crateriform disk composed of connate tepals (perigon). Perigon persistent, abaxial and adaxial surfaces light green, glabrous. Stamens 5-25 per flower, exserted. Anthers glabrous, dehiscing longitudinal. Filaments free, straight, white, glabrous. For a review of the floral micro-anatomy and vascularization see Fisher, 1928. For a review of the floral micro-anatomy, vascularization and micro/mega-sporogenesis see Nagaraj, 1952.
FRUITS Loculicidal 2-valved capsule, green, ovoid, 2-5.5 mm long, 1.5-2 mm wide, glabrous, bearing 6-15 seeds.
SEEDS Seeds 0.5 mm long, glabrous, adnate tufts of "cotton" (which facilitate anemochory) composed of epidermal hairs of the placenta. Endosperm completely consumed by developing embryo so that none remains in the mature seed (Nagaraj, 1952).
HabitatAggressive pioneer species, not shade tolerant; neither does it tolerate long-term flooding nor waterlogged soils. Quaking aspen occurs on a wide variety of sites and soils. It grows on moist upland woods, dry mountainsides, high plateaus, mesas, avalanche chutes, talus, parklands, gentle slopes near valley bottoms, alluvial terraces, and along watercourses. Quaking aspen is highly competitive on burned sites. (Howard, 1996) (Fowells, 1965)
Indigenous to most of North America except the southeastern United States. Quaking aspen is the most widely distributed tree in North America. (Howard, 1996) (Fowells, 1965)
United States -- AK, AR?, AZ, CA, CO, CT, DC, DE, IA, ID, IL, IN, KY?, MA, MD, ME, MI, MN, MO, NC?, ND, NE, NH, NJ, NM, NV, NY, OH, OK?, OR, PA, RI, SD, TX, UT, VA, VT, WA, WI, WV, WY
Canada -- AB, BC, MB, NB, NF, NS, NT, ON, PE, QC, SK, YT
New York Metropolitan Region -- Native, found throughout the metropolitan area.
Global Heritage Rank -- G5
Connecticut -- Not listed
New Jersey -- Not listed
New York -- Not listed
March [week 4] - April
Anemophily (Fowells, 1965)
April [week 2] - May
Good crops every 4-5 years with light seed crops during most of the intervening years (Fowells, 1965) Quaking aspen first flowers at 2 to 3 years. Minimum tree age for production of large seed crops is 10 to 20 years, and maximum seed production occurs at about 50 years of age. There are 3- to 5-year intervals between heavy seed crops. (Howard, 1996)
Anemochory and Hydrochory (Fowells, 1965) (Howard, 1996)
It is difficult to define germination with the small seeds of Populus species; for most species; germinated seedlings should have well-developed hypocotyl hairs, regular growth, and a geotropic response. Seeds that have been dried for storage may suffer injury from rapid imbibition; aeration with humid air after storage has been used to solve this problem. The critical factor for germination is moisture. (Young & Young, 1992)
The time of ripening is quite variable; a safe criterion for time of fruit collection is when a small percentage of the capsules are beginning to open. Pre-strorage drying immediately after collecting is essential for successful storage. A moisture content of 5-8% improves viability and germination of stored seed. After air drying for 4 days store in a sealed container at 41d F. The critical factor for germination is moisture. (Dirr & Heuser, 1987)
Can germinate while floating or submerged; not dependent on light, and with sufficient moisture germination will take place between 0-35dC. Optimum in media of pH 7-8.5; temp. 29-32dC. Most seeds lose viability after 18 weeks. (Faust, 1936)
Viability of fresh seed is good; germination of 80 to 95 percent is reported under laboratory conditions. (Howard, 1996)
Long term viability can be maintained with temperatures below freezing in a dry atmosphere. (Stettler et al, 1996)
Also regenerates readily from roots suckers and stump sprouts. (Fowells, 1965) (Howard, 1996)
For a review of the literature concerning suckering dynamics see Frey, 2003
For a propagation protocol for bareroot quaking aspen using seeds see Day, 2003.
Natural hybrid with P. grandidentata (= P. x smithii) (Fowells, 1965) (Stettler et al, 1996) (Howard, 1996)