Autumn olive (Elaeagnus umbellata)

Light leaf undersides and immature fruit of autumn olive.

 
 

Autumn olive is a shrub or small tree that has distinctively silvery leaves. It grows in a range of habitats, including forest edges, savannas, pastures, and prairies.

Description

Appearance

Autumn olive is a shrub that can grow up to 20 feet tall and 30 feet wide. It has distinctively silvery leaves and large red berries.

Leaves and Stem

Autumn olive leaves are oval with a slightly wavy edge. Leaves are 2-4 inches long and taper at the tips. The leaves are grayish green with uniquely silvery scales on the underside of the leaves. Like many invasive shrubs, it leafs out early in spring and holds onto its leaves into the fall.

Young twigs are silvery with golden brown scales, giving them a speckled appearance. Branches often have thorns that can be inches long on young branches. Mature bark is light gray to gray-brown.

Flowers

Fragrant cream to pale yellow flowers bloom in early spring, from April to June. Flowers bloom in clusters of 1-8 bell-shaped flowers.

Seeds

Fruits are silvery with brown scales when young and change to a speckled red when mature. A single shrub can produce up to 30 pounds of fruit containing 66,000 seeds each year. Birds are attracted to the fruits and spread the seeds.

Roots

Autumn olive has an extensive root system that extends beyond the edges of the crown.

Biology

Autumn olive can spread in a wide range of habitats including forest edges, meadows, open woods, pastures, riverbanks, roadsides, and disturbed areas. It has nitrogen-fixing root nodules that change soil chemistry and allow it to survive in poor soils. Autumn olive can survive in moderate shade as well as full sun.

Origin and Spread

Autumn olive was introduced to the United States from Asia in the 1830s. It was originally planted for erosion control and as wildlife habitat in disturbed areas.  Seeds are spread by birds and other wildlife. Fruit persists on the shrub into the winter, when there is little other food available to wildlife. As one of the few winter food sources it is widely eaten by wildlife, contributing to its spread.

Refer to EDDMapS Distribution Maps for current distribution.

Don't be fooled by these look-alikes

  • Russian olive, Elaeagnus angustifolia (invasive) – has longer, narrower leaves that are silvery on top as well as on the underside.
  • Non-native bush honeysuckles, Lonicera spp. (invasive) – leaves are arranged opposite each other along the twigs and they do not have silvery scales on leaves or twigs.
  • Silverberry, Elaeagnus commutata (native) – leaves remain silvery-green on the upper surface through the season, has dark yellow flowers, and larger, pale yellow fruits.
 
Regulatory Classification

This species is not regulated in Minnesota.

Threat to Minnesota
  • Autumn olive can shade out and outcompete native plants.
  • It changes soil chemistry by increasing nitrogen levels. This can degrade plant communities adapted to low-nutrient environments, such as barrens and prairies. It can promote growth of fast-growing weedy species in such habitats that displace native plants.
What you should do

One way that invasive plant seeds and fragments can spread is in soil.  Sometimes plants are planted purposefully.  You can prevent the spread of invasive plants.

PlayCleanGo: Stop Invasive Species in Your Tracks

  • REMOVE plants, animals & mud from boots, gear, pets & vehicle.
  • CLEAN your gear before entering & leaving the recreation site.
  • STAY on designated roads & trails.
  • PLANT non-invasive species.
Native Substitutes
 
Control Methods

Mechanical control can be done by digging or pulling the plant by hand. Cutting or mowing following up with herbicide application is not recommended because it can stimulate resprouting in mature autumn olive plants.

Herbicide control can be done using systemic herbicides, which are taken up by plants and move within the plant, killing leaves, stems, and roots. Cut plants will resprout if the stump is not treated with herbicide after cutting. Immediately after cutting (within 2 hours), apply an herbicide containing triclopyr (Garlon 3A/Vastlan, Garlon 4, or other brush killers with triclopyr) or glyphosate (Roundup) to the cut stump to prevent re-sprouting. Always follow label instructions for herbicides. Herbicides can be applied to cut stumps with a paintbrush, wick applicator such as a dauber or "buckthorn blaster," or a low volume sprayer.

In cases where more than a few plants are treated, add an indicator dye (available where pesticides are sold), such as Mark-It Blue, to the herbicide to mark which cut stumps you have sprayed.

For basal stem treatment, a method that applies chemical through the bark, low volume spray applications can be made with Garlon 4, Pathfinder II and similar oil-based products. This application method uses triclopyr ester mixed with an oil diluent (i.e. Bark Oil Blue, kerosene) applied directly to the bark of autumn olive from the root collar up about 12-18 inches. An ultra-low volume spray wand should be used to minimize herbicide use and reduce the potential for non-target injury.

Reporting

This species is unregulated, but you can add to the public information about this species by reporting new occurrences through EDDMapS Midwest.

Resources