Siberian elm (Ulmus pumila) growing near the Truckee River in Reno, Nevada. Photo: Kelsey Fitzgerald.
- Leaves: small, serrated edges, parallel veins. Alternate arrangement on branch.
- Flowers: Feb-Mar. Small and brown.
- Fruit (seeds): Mar-Apr. Green, fading to brown as they dry. Disc-shaped and papery.
- Bark: Gray-brown, deeply furrowed.
You may recognize this tree from—well, everywhere. You’ll find it growing along the banks of the Truckee River, in yards, on roadsides, under fences… Siberian elm are weedy and fast-growing, and were introduced to the U.S. from Asia in the 1860s (Moore & Davis 2003). They have now spread across much of the U.S., and are thriving in the Reno area.
In early spring (Feb-March), look for the tiny brown flowers of the Siberian elm, which bloom before leaves emerge, hugging close to the tree’s bare branches. Pollinated by the wind, the papery green “fruit” of the elm develop a few weeks later. When the fruit falls and dries, you will find the disc-shaped seeds blowing all over town.