The state flower of Oregon is the Oregon grape, sometimes called Oregon grapeholly. Not related to more familiar grapes, this shrub is named after the clusters of berries that hang from its branches, reminiscent of traditional grapes. This plant may be listed under two different scientific, or botanical, names due to a debate between botanists as to which genus it actually belongs. Mahonia aquifolium and Berberis aquifolium are both used for this plant.
Officially designated the state flower of Oregon in 1899, the Oregon grape is also commonly known as mahonia. Thought to be related to barberry, this plant is sometimes placed in the same genus, Berberis, as barberry plants. Though the Oregon grape can be found in parts of Washington and California, its primary range is in Oregon, hence its name.
Although these plants are considered evergreen, since they never lose their leaves, the leaves do change to a dark purple shade in winter months. The leaves are longer than they are wide, usually 2 or 3 inches (5–7.6 cm) in length. Similar to holly, the leaves are smooth but pinnated, having small spikes around the edges. Branches contain pairs of leaves along their length, plus a single, unpaired leaf. The rich green leaves have a natural shine and are also used in floral displays for striking foliage.
Blooming in the spring, the yellow flowers occur in small clusters, most often near the end of branches. Six sepals, or the small leaves that enclose a budding flower, surround six petals. At the base of the flower blossom, three bracts, or scale-like leaves, are found.
After blooming, small clusters of dark blue berries are formed. Each berry is only 0.3–0.5 inches (0.7–1.3 cm) wide. Hanging like grapes, these berry clusters are where the state flower of Oregon gets its common name.
The shrub itself grows rapidly and can reach heights of 6 feet (1.8 m). Low maintenance and showy in the Spring and Autumn particularly, Oregon grape shrubs are often used in landscaping. The shrub's drought resistance adds to its desirability.
Beginning with the Native Americans centuries ago, the state flower of Oregon is still used for medicinal purposes. The woody yellow roots can be used to treat skin diseases like psoriasis, eczema, and acne. There is also evidence the plant may help increase the effectiveness of certain antibiotics by lowering bacteria's resistance to them. The leaves, when torn and boiled, can also be used to make a yellow dye, and the berries serve to make purple dye.