Russian olive is a small ornamental tree native to western and central Asia.
It was introduced to North America because of its attractive silver leaves, cold hardiness, and tolerance of low humidity and drought. Russian olive has small, fragrant yellow flowers and edible silver berries that are sought after by wildlife. However, it has escaped cultivation and has become highly invasive.
How does it spread?
Russian olive is successful because it is a post-disturbance colonizer that produces prodigious quantities of long-lived seeds, which are dispersed in the droppings of birds and small mammals that forage on the berries, as well as by flowing water. Further spread occur directly by intentional human introduction and indirectly by the activity of beavers which aid population establishment.
Where would I find it?
Russian olive, with its deep taproot and well developed root system, is tolerant of a variety of adverse conditions, including drought and saline, alkaline or infertile soils. The species grows well in moist to dry areas, from riparian areas and wetland margins to forests and grasslands. Its nitrogen-fixing ability allows it to grow on thin, mineral soils. Russian olive is also somewhat fire resistant and establishes easily in burned over areas.
What problems does it cause?
Russian olive displaces native vegetation, exploits the limited water resource, decreases critical wildlife habitat and interferes with natural plant succession and nutrient cycling where it has escaped cultivation and invaded dry areas. It is challenging if not impossible to eradicate or control as it re-sprouts from cut stems and spreads quickly by bird dispersed seed, often becoming the dominant woody plant in the ecosystem.
- Weeping Pear (Pyrus salicifolia) (z4)