Autumn Olive is a plant native to Asia that was first brought to the United States as an ornamental in the 1830’s. It has egg shaped green leaves with silver undersides and red berries that have small silver scales. It is deciduous and can routinely grow to 20 feet in height and 30 feet in width.
In the 1950’s, soil conservation organizations started to use it widely for erosion control and things snowballed from there, resulting in one of the more notorious invasive plant problems that we face.
We were recently hiking at Twin Creek Metropark near Dayton Ohio. Early in the hike, as can be seen in the title photo, we were coming up a slight grade in what appeared to be an old farm field, and the trail was basically fenced in by run away Autumn Olive plants. In this former pasture there were countless Autumn Olives, from 1 to 25 feet in height.
The problem with invasive plants, and Autumn Olive specifically, is they out compete the native plants. They leaf out earlier in the spring and drop their leaves later in the fall, blocking their native competitors from sunlight. We saw several examples of this competition on our hike.
Here you can see it growing up through a Redcedar tree,
and here displacing one of our native sunflowers, the Jerusalem Artichoke.
Autumn Olives are proficient reproducers with plants yielding up to 200,000 berries per season.
The berries are consumed by wildlife, especially birds, with the seeds passing through their digestive tracts to be deposited elsewhere, spreading the plants far and wide. We certainly saw that at Twin Creek.
The berries are edible to humans but the single somewhat soft seed is a bit large for the rather meager flesh of the fruit. When I tasted them in August they were still somewhat bitter, but that usually improves as the temperature cools in the fall.
Eradicating Autumn Olive is a challenge. You can pull them out but the shear number of plants is too overwhelming for that labor intensive exercise. Prescribed burning generally is not successful as the roots survive and the plants tend to be the first to recover, again giving them competitive advantage over the native plants.
Drastic times call for drastic measures and therefore many authorities recommend targeted application of herbicides. That was the approach they were using at Twin Creek, where we traversed a field that had numerous plants that had been effectively treated with a herbicide.
We will never be able to eradicate Autumn Olive entirely but herbicide application, especially at ecologically critical sites, will allow the native plants to thrive without competition from this non-native aggressor.