top navigation:

Native Plant Propagation Guidelines:
shrubs

Mahonia nervosa (dull Oregon-grape)

Category: 
shrubs

dull Oregon-grape (photo by Carolyn Masson)

An erect evergreen shrub reaching 60 cm tall. Compound leaves resemble holly and are clustered at the base, with nine to nineteen leathery and spiny leaflets that turn purplish in winter. Flowers are bright yellow racemes, becoming edible berries with large seeds and a whitish bloom (Pojar and MacKinnon, 1994). Photo by Carolyn Masson.

Scientific Name: 

Mahonia nervosa (Pursh) Nutt. (Berberis nervosa Pursh)

Family: 
Berberidaceae
English Name: 
dull Oregon-grape
Other Names: 
longleaf hollygrape, creeping hollygrape, cascade Oregon-grape

Geographical Range and Habitat Requirements

Ecological Setting: 

Mesic to dry open slopes and open forests in the lowland, steppe and montane zones (Douglas et al., 1998). Dry to fairly moist, open to closed forests at low to middle elevations (Pojar and Mackinnon, 1994). Scattered to abundant, occasionally dominant in the understory of semi-open forests (persists on cutover sites) on water-shedding sites (Klinka et al., 1989). Can grow in the understory of 300-600-year-old forests and in open meadows and recent clear cuts (Tirmenstein, 1990).

Soil Texture: 

Coarse, skeletal soils (Klinka et al., 1989). Coarse, shallow, rocky soils, coarse alluvium, or glacial outwash.

Nutrients: 

Nitrogen medium soils (Klinka et al., 1989).

Soil Reaction and Salinity: 

Acidic to moderately alkaline. Moderately saline tolerant (Tirmenstein, 1990).

Moisture Regime: 

Moderately dry to slightly moist regimes (Klinka et al., 1989). Well to poorly drained (Tirmenstein, 1990).

Shade Tolerance: 

Grows well in sun or shade (Tirmenstein, 1990).

Successional Status: 

Understorey dominant in early seral stages after low-intensity fires but persists into later seral stages because of its ability to tolerate shade (Tirmenstein, 1990).

BEC Zone and GOE Community Status: 

Associated with oceanspray in the Garry oak-oceanspray community (Klinka et al, 1989).

Uses

Site Rehabilitation: 

Useful for erosion control and site stabilization because of its rhizomatous habit and wide range of shade tolerance (Minore et al., 1996).

Wildlife: 

Browsed by black-tailed deer and Roosevelt elk; foliage eaten by various small mammals, and fruit eaten by many small birds and mammals. Nectar eaten by Anna's hummingbird (USDA, 1988; Tirmenstein, 1990).

Landscaping: 

Popular ornamental. Good ground cover under conifers or deciduous trees (B. Costanzo, personal communication). Four season characteristics – showy bright yellow flowers; grape-like edible fruit; good fall/winter colour. Use on banks or as a ground cover. Good compact habit so could be used in a short border and for ground cover in a woodland setting (S. Bastin, personal communication).

First Nations: 

Fruit eaten mixed with salal and some other sweetening fruits. Shredded bark or roots used to dye basket materials bright-yellow. Bark and berries used medicinally for liver, gall-bladder and eye problems. Berries eaten in quantity as an antidote to shell-fish poisoning (Pojar et al., 1994).

Other Uses: 

Can be used to make jelly. Roots contain an alkaloid (berberine) with anti-bacterial properties (Minore and Rudolf, 1996).

Seed Propagation

Flowering Time: 

Early to late spring (Rose et al., 1999)

Fruit Ripening Time: 

July - August

Seed Collection Time: 

August - September. Fruit should be collected when berries are purplish-blue in colour.

Crop Intervals: 

Annual

Number of Seeds per Kilogram: 

50,705-66,140 (Rudolf, 1974)

Seed Viability: 

Up to 90%

Fruit and Seed Collection and Extraction: 

Use gloves to collect berries or flail from shrubs onto cloths. Clean by macerating with water and allowing pulp to float off (Rose et al., 1998).

Seed Storage: 

Seeds should be superficially dried and sown immediately or store in sealed containers at 2-4º C (Minore and Rudolf, 1996; Rose et al., 1998).

Fruit/Seed Dormancy and Treatment: 

Sow immediately in 1.25 cm of soil, covered with 0.6 cm of sand, and stratify over winter under mulch. Spring-sown seeds should be cold stratified for six to ten weeks at 4oC (Minore and Rudolf, 1996).

Vegetative Propagation

Method Success Rate Time of Collection
Softwood cuttings Good Early summer
Semi-hardwood cuttings n/a n/a
Hardwood cuttings Healed, nodal or basal cuttings treated with rooting hormone (Minore and Rudolf 2001). Late fall or winter
Root cuttings Moderate to good from rhizomes (Rose et al., 1998)  
Suckers  n/a n/a
Plant division Good Spring or fall

Remove spines and leaves and treat with rooting hormone. Use 2:1 vermiculite:sand mixture in a cold frame (Huxley et al., 1992).

Outplanting Characteristics and Requirements

Outplant after two years (Rudolf, 1974; Foster, 1977). Slow to establish; plant in sun to partial shade (best in partial shade) in moist to dry soil. Space approximately two feet for cover (S. Bastin, personal communication)

Seed and Cutting Propagation Techniques

n/a

Additional Information and Photos

For more information and pictures, visit the E-Flora BC website at www.eflora.bc.ca.