Photo credit: Nancy Loewenstein, Auburn University, retrieved from Bugwood.org (Image Number: 5306027), used under CC BY-NC 3.0 US, modified from the original
Common Name: Autumn Olive
Scientific Name: Elaeagnus umbellata
Habitat: along streams, ornamental
Provincial Designation: Prohibited Noxious
Prohibited Noxious weeds are plant species designated in the Alberta Weed Control Act. Prohibited noxious weeds must be destroyed, meaning all growing parts need to be killed or the plant's reproductive mechanisms need to be rendered non-viable.
Autumn olive is native to Asia and was brought to North America. It has been grown as an ornamental shrub, for food and cover for livestock, and as a windbreak.
Autumn olive can grow into dense thickets and out-compete native vegetation. It also has nitrogen-fixing roots that can change the nutrient cycle in the soil making it difficult for native species that depend on poor soils to grow.
Autumn olive is a deciduous shrub that grows up to 4 m tall. The flowers are fragrant and have four white or light yellow sepals.
The characteristically silvery single leaves have smooth, wavy edges and are egg-shaped (2-7 cm x 1-2 cm). The branches have single thorns about 2½ cm long. Shoots and young branches have silvery scales on them which disappear when it rains making it an important identifying feature.
Autumn olive fruits are 1 cm long, red and juicy with silver dots.
Can Be Confused With
Russian Olive - Elaeagnus angustifolia - introduced, more likely to have rusty scales on leaves and branches, berries are orangey-red.
Buffaloberry - Elaeagnus commutata - native shrub, usually smaller with more stems per plant, lots of rusty spots on the bottom of the leaf.
Learn more about this species:
See Fact Sheet — Alberta Invasive Species Council