Autumn olive leaves and berries. Image credit: August Camp.

Autumn olive leaves and berries

Image credit: August Camp

Autumn Olive

Elaeagnus umbellata

Characteristics

Autumn olive is a small, woody tree known for invading open prairies, disturbed areas, and woodland edges. It houses nitrogen fixing bacteria on its roots, allowing for rapid growth and colonization, while also altering soil conditions. 

  • typically grows up to 15 feet high and 20 feet wide, branching from multiple stems
  • alternate green leaves with a distinct silvery underside and wavy margins
  • stems have 1 inch thorns and new growth is reddish with distinct silvery speckles or scales
  • flowers are cream colored with four petals and bloom around May, turning into yellow or red drupes later in the season

Another key identifying feature of autumn olive are the root nodules visible on plants when physically pulled from the ground. These nodules are bumpy and white, and house bacteria in the genus Frankia, allowing for nitrogen fixation.

For more information, visit Woody Invasives of the Great Lakes (WIGL) Collaborative and Midwest Invasive Species Information Network (MISIN).

Autumn olive branch

Autumn olive with yellow drupes

Image credit: August Camp

Autumn olive speckled branches

The speckled stem of autumn olive

Image credit: August Camp

Autumn olive roots

Autumn olive roots

Image credit: August Camp

Autumn olive root nodules

Root nodules on autumn olive

Image credit: August Camp

KISMA Management Practices

Autumn olive is a prevalent invasive in downstate Michigan, and has a spotty distribution throughout the upper peninsula. Managing this species is similar to managing other woody invasives like common and glossy buckthorn. 

  1. use root wrenches or shovels to loosen root ball and remove as much of the root mass from the soil as possible
  2. hang pulled shrubs upside down to dry, dispose of plants in a landfill, or burn pulled plants if the shrub contains berries
  3. if trees are too large for manual pulling, cut the tree a few inches above the ground and cover with thick trash bag, secure bag to stump with zip tie, spread bag over soil around stump, and weigh the bag down with rocks or wood. Leave the bag in place for two growing seasons. This smothering technique will prevent stump sprout regeneration and kill the root mass.
  4. it is easiest to remove small saplings by hand before they become well established 

Note: Autumn olive can easily regrow if large amounts of root mass is left in the ground, so care should be taken to remove as much of the root from the ground as possible. Wearing protective gloves and sleeves is encouraged due to the thorns present on this plant. Hanging or burning removed plant material is acceptable, however, care should be taken to remove all present fruits before transporting or hanging the pulled material. 

Native Alternatives 

Species such as beaked hazelnut (Corylus cornuta) and downy arrow-wood (Viburnum rafinesquianum) are native understory shrubs that inhabit forest edges similar to autumn olive. Red-osier dogwood (Cornus sericea) and highbush cranberry (Viburnum trilobum) are also good alternatives for replanting in wetland edges and riparian areas.