For more Oregon reading , check out: 1  These Are The 10 Best Places To Retire In Oregon. 2  These Are The 10 Most Miserable Cities In Oregon. 3  These Are The 10 Drunkest Cities In Oregon.
A perennial plant or simply perennial is a plant that lives for more than two years. The term is often used to differentiate a plant from shorter-lived annuals and biennials.
A perennial stream or perennial river is a stream or river (channel) that has continuous flow in parts of its stream bed all year round during years of normal rainfall.he boundaries between perennial, intermittent, and ephemeral channels are indefinite, and subject to a variety of identification methods adopted by local governments, academics, and others with a need to classify stream-flow permanence.