Populus tremuloides : Trembling Aspen


Scientific Name:

Kingdom: Plantae


Class: Dicoteldonae (two seed-leaves)

Family: Salicaceae (Willow Family)

Genera: Populus (Poplar) (Lat. classic latin name for poplar trees)

Species: tremuloides (Lat. tremulus=trembling, quivering, referring to the trembling of the leaves in even slightest wind.)

English Name(s):

Trembling Aspen, Quaking Aspen, White Poplar, Mountain Aspen

First Nation Names:




  • Bark smooth chalky white to greenish-white. Bark becoming furrowed on oldest trees.
  • Slender tree up to 12 meters tall occasionaly taller, but often much shorter.
  • Trunk diameter not usually greater than 30cm.


  • 3-7 cm long. by 1-6 cm wide. Ovate, short-acuminate in shape.
  • Fresh green above and paler below.
  • Have a flat petiole (stalk). This is what allows them to tremble in even the slightest breezes.
  • In Yukon often silvery-green in colour by mid-summer due to a widespread leaf miner outbreak.
  • Margins finely crenate.

Reproductive Parts:

  • Female flowers 5-10mm long.
  • Flowers born in drooping catkins.
  • Male flowers with 5-12 stamens.
  • Trees dioecious (unisexual).


  • Fruit is a capsule slenderly conic in shape, 3-5mm long.
  • Seeds have long hairs and are spread by the wind up to 30 km.

Not to Be Confused With:

  • Populus balsamifera is the only other poplar in our area. It can be distinguished by its rougher bark, different shaped leaves, and its round rather than flat petiole (leaf stalk).
  • When holding a P.balsamifera (Balsam Poplar) leaf by its petiole (stalk), it will roll between two fingers. The leaf of P.tremuloides (Trembling Aspen) will not roll between your fingers.



  • P.tremuloides reproduces primarily vegitatively by suckering (shoots from roots). Trees arrising from suckers are clones of the parent tree.
  • All the trees in a Aspen stand maybe clones of a single tree. While they may all look like individual trees, they are all connected underground by thier roots. The largest organism in the world is a clone stand of P.tremuloides( Trembling Aspen).
  • Aspen bark has chlorophyhyll (green light collecting pigment) and is photosynthetic.
  • One can tell if poplars in a stand are clones or separate trees by the timing of the budding of leaves, bearing of catkins, and colouring of leaves in the autumn. All the trees of a single clone will do these things at the same time as eachother.
  • The sunny side of aspen trunks and branches produce a white chalky substance to shield it from to much sun.
  • Though every leaf on a tree may be infected by leaf miners. The infection apears to not kill the trees.
  • Though the famale trees can produce millions of seeds each year. The seeds are only viable for 3days-3weeks and most will not germinate.

Life Cycle:

  • Fast growing tree lives about 80 years.

Seasonal Cycle:

  • Catkins apear in the spring well before the leaves.
  • Leaves deciuous (dieing back). They turn yellow in autumn before falling off by late September.


Animal Uses:

  • In spring the catkins are loved by bees seeking wax.
  • In times of need ungulates will eat the bark leaving extensive scars on the lower trunk.
  • In Yukon more often than not the leaves of these trees are infected by leaf miners.
  • Many ungulates will browse on the tender young twigs and leaves.
  • One can see where bears have climbed aspens as their claws scratch deep into the soft bark and leave long grey scars.
  • Poplars are the preferred food of beavers.


  • Common forest species. Often on dry south facing slopes in central Yukon.




  • Experiments have shown that they can be grown and harvested every 2 years as a crop; or harvested every 10 years for fuel and fiber; or harvested every 30 years for timber.
  • Wood is used comercially for making toothpicks.


  • Astringents salicin and populin in the inner bark undoubtedly draw cuts together and speed healing.
  • The inner bark is said to contain a quinine substitute.


  • Leaves contain 20-30% of thier dry weight in protien. A concentrate has been produced from the leaves that is almost as nutritional as meat and can be produced more quickly and cheaply.
  • Leaves taste somewhat like spinach and are very nutritious.
  • The inner bark can be eaten as emergency food or dried and ground to flour.
  • The sap can be drunk or boiled down into a syrup.

Traditional Gwich'in:





          Traditional Other:


          • Acording the the Victorian Language of Flowers these plants symbolize lamentation and fear.
          • In many languages the name for P.tremuloides translates as "woman's tongue".
          • In Sicily it is cutomary on solstice eve to cut down the tallest poplar and drag it through the village while shouting and beating a drum. A crowd dances and sings around the tree.
          • Inner bark was used in a smoking mixture by Plains Indians.
          • The aspen is said to have provided the wood for the Cross of Christ and its leaves still tremble remembering His Passion.
          • The bark was thought to make women barren if it was drunk with the kidney of a mule.
          • The poplar was sacred to Hercules because when bitten by a snake he found a remedy for the poison in its leaves.


          • Blackfoot used the trunks for centre poles of cerimonial lodges.
          • Cotton from the seeds has been used to make cloth and paper.
          • Leaves and twigs dye wool grey, gold and brown.


          • Chippewa would spit in a cut, draw the edge together, chew aspen bark or root and apply it thickly as a poultice as soon as possible.
          • Leaf or Bark tea was used for fever, rheumatism or arterial swellings. It was also used as a wash for cuts, wounds, sore arms and legs, gangrenous wounds, eczema, burns, body odour, and even cancer.
          • Roots were steeped but not boiled and the tea given every hour to pregnant mothers when close to birthing to reduce excessive flow and premature birth. (Chippewa)



            Typical leaf.

            Smooth greenish-white bark.

            Female catkins going to seed.

            Catkin in flower.

            Illustration from: Illustrated Flora of BC

            Range Maps

            World Range: Boreal North America; From NL to AK south to VA and Mexico.

            Prov/State Abrev. List

            In Yukon: Widespread north to Porcupine River.

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