April 21, 2024

How the Russian Olive Became a Villain

Yesterday's hero (famous writer, movie star, politician) is the villain of today. There is a lot of that going around — even with trees. Take kudzu. That was like the Fatty Arbuckle of introduced species; everybody "knew it."

My area has seen some heavy snow and quite a few high winds in the past month. Anybody with a chainsaw and a wood chipper has lots of new close friends. At one nearby house, the snow broke a big old Russian olive tree, and while the people there decided to keep its thick trunk as a sort of lawn ornament, I ended up with the branches.

I rarely turn down free firewood. I have never burned Russian olive, a.k.a. oleaster, but when your go-to firewood is pine, any hardwood seems like a bonus.

Among Dad's old forestry books and field guides was Common Forest and Windbreak Trees of Colorado, published by the Colorado State Forest Service in 1963, and like most of that agency's work, geared toward private landowners, particularly those wanting to plant shelterbelts (windbreaks) around houses and outbuildings on the windswept prairie. 

Russian olive (Columbia Univ.)

Elaeagnus angustifolia
was praised. "Drought resistant and makes rapid growth . . . the fruit is relished by insect-eating songbirds and other wildlife."

In the West, tamarisk is our kudzuand both are being hunted with insects. But Russian olive has been "cancelled" too.  

I learned that at some conference in northern New Mexico a few years back, when I ended up talking trees with the environmental manager for Pícuris Pueblo, and she was like "Death to Russian olives!"  True: In New Mexico and Nevada it is officially a "noxious weed," while California, Nebraska, Wisconsin, and Wyoming label it an "invasive weed."

Background from a Columbia University site on introduced species (archived version):

The Russian olive was introduced to the central and western United States in the late 1800’s as an ornamental tree and a windbreak, before spreading into the wild. By the mid 1920’s it became naturalized in Nevada and Utah, and in Colorado in the 1950’s. . . .

 Its value for wildlife is a "yes, but":

The "olives" (Columbia Univ.)

Over 50 different species of mammals and birds do eat the fruit, 12 of them being game birds. Deer and other livestock feast on the leaves of the Russian olive and beavers use the branches for constructing dams. The canopy of the Russian olive provides good thermal cover for some wildlife species. Doves, mocking birds, roadrunners and other birds use the thick growth of branches as nesting sites.

The Russian olive, with its tendency to spread quickly, is a menace to riparian woodlands, threatening strong, native species like cottonwood and willow trees. They are responsible for out competing a lot of native vegetation, interfering with natural plant succession and nutrient cycling and choking irrigation canals and marshlands in the western United States. This displacement of native plant species and critical wildlife habitats has undoubtedly affected native birds and other species. The heavy, dense shade of the Russian olive is also responsible for blocking out sunlight needed for other trees and plants in fields, open woodlands and forest edges. Overall, areas dominated by the Russian olive do not represent a high concentration of wildlife.

And they are hard to kill, spreading from suckers when the main trunk is cut. It sounds like brush-hogging with some herbicide is the way to control them; there is no natural pest to be imported, according to the site that I linked to.

Dad planted one in our backyard in Lakewood, Colo., along the high cedar fence he built. I remember its silvery leaves. But when I look down at that yard in Google Earth today, it appears to have been replaced by other trees, a pushback against the invasion.