Ulmus rubra (Red Elm)


Botanical Information

FamilyUlmaceae
GenusUlmus
Speciesrubra
CategoryWoody
TypeTree (deciduous)
References2014 Richard Dickinson, Plants of Southern Ontario, (pg. 41) 2009 Michael A. Dirr, Manual of Woody Landscape Plants, (pg. 1166)
OriginNative to south eastern Canada and the United States of America.
Ethnobotanical Uses
Disclaimer
The bark of the Red Elm has been known for its ability to quench the thirst of the early pioneers of North America, which is how it came to get the name Slippery Elm. The inner layer of bark is also known to help with urinary tract infections, burns, diarrhea, sore throat, and helps heal flesh wounds.

Details

USDA Hardiness Zone3 - 7
USDA Hardiness Ref.
Canadian Hardiness Zone1 - 7
Canada Hardiness Ref.
RHS Hardiness ZoneH2 - H3
RHS Hardiness Ref.
Temperature (°C)-15 - 24
Temperature (°F)5 - 54
Height15 - 35 m
Spread20 - 30 m
GrowthFast
Flowering PeriodMarch, April, May

Description and Growing Information

General DescriptionThe tree is vase shaped with a flat topped crown and brownish-red bark.
ID CharacteristicLeaves are alternate, with acute apex, and 5-10 cm long. They are serrated with a hairy underside. Red Elm has a unique flower that appears in early spring before the leaves emerge. The flowers are found in clusters of 3-7. Very definable bark that has a brownish-red colour to it, and has striped fissures rather than diamond fissures which can be found in the American Elm (a close relative).
ShapeA medium upright tree, that maintains the same shape throughout its life.
Landscape
Propagation
CultivationThrives in rich moist soils that are slightly acidic. Can persist in soils with poor drainage, but it is intolerant of wet soils and polution.
PestsSusceptible to Dutch Elm Disease and the Elm Leaf Beetle.
Notable Specimens
HabitatFound at the bottoms of moist valleys and besides rivers and streams.
Bark/Stem DescriptionThe bark is brownish-red in colour with striped fissures, and does not change due to age or season.
Flower/Leaf Bud Description3+ scales on winter buds; brown, pointy, small, and opposite.
Leaf DescriptionLeaves are bristly, hairy, alternate, oval or oblong and have a doubly serrate margin. Leaves change from a green to a bright yellow in the autumn.
Flower DescriptionMonoecious, small flowers in clusters in groups of 3-7. Flowers are light to medium green, borne in early spring, and have no ornamental value.
Fruit DescriptionThe fruit has a winged-like surface, is usually only 2-3 cm long, and ripens in late spring.
Colour DescriptionThe bark is brownish red, and does not change colour throughout its lifespan or season. The canopy is a medium green and turns to a bright yellow in the autumn.
Texture DescriptionThis plant has a coarse texture, unchanging through age and season.

Photographs