The Riverbank Wildrye (Elymus Riparius) is generally described as a perennial graminoid. This monocot (monocotyledon) is native to the U.S. (United States) has its most active growth period in the spring and summer . The greatest bloom is usually observed in the mid summer, with fruit and seed production starting in the summer and continuing until fall. Leaves are not retained year to year. The Riverbank Wildrye has a moderate life span relative to most other plant species and a moderate growth rate. At maturity, the typical Riverbank Wildrye will reach up to 4.5 feet high, with a maximum height at 20 years of 0 inches. The Riverbank Wildrye is easily found in nurseries, garden stores and other plant dealers and distributors. It can be propagated by seed. It has a moderate ability to spread through seed production and the seedlings have high vigor. Note that cold stratification is not required for seed germination and the plant cannot survive exposure to temperatures below -33°F. Riverbank Wildrye has low tolerance to drought and restricted water conditions. Plant Basics: Category : Monocot, Growth Rate : Moderate, General Type : Graminoid, Growth Period : Spring, Summer, Growth Duration : Perennial, Lifespan: Moderate, Plant Nativity: Native to U.S., Commercial Availability : Routinely Available. Physical Characteristics: Bloom Period : Mid Summer, Displays Fall Colors: No, Shape/Growth Form: Bunch, Drought Tolerance : Low, Shade Tolerance : Tolerant, Height When Mature : 4.5 feet, Vegetative Spread : None, Flower Color : Yellow, Flower Conspicuousness: No, Fruit/Seed Abundance : Medium, Fruit/Seed Seasonality : Summer Fall, Seed Spread Rate : Moderate, Gardening Characteristics: Propagations (Ways to Grow): Seed, Moisture Requirements : High, Cold Stratification Required: No, Minimum Temperature : -33, Soil Depth for Roots : 10, Toxic to Nearby Plants : No, Toxic to Livestock : No, After-Harvest Regrowth Rate : Slow, After-Harvest Resprout Ability : No, Responds to Coppicing : No, Growth Requirements: pH Range: 4.5–7.2 pH, Precipitation Range: 24–24 inches/yr, Soil Textures : Coarse, Fine, Medium, Soil Depth for Roots : 10, Minimum Frost-Free Days : 100 days, Salinity Tolerance: None, CaCO3 Tolerance: Medium, Sustainability & Use: Leaf Retention: No, Fire Resistant: No, Causes Livestock Bloating : None. Source: USDA, NRCS, PLANTS Database, plants.usda.gov. National Plant Data Center, Baton Rouge, LA 70874-4490 USA