Monthly Archives: June 2015

Low Oregon Grape, Mahonia nervosa

Low Oregon Grape                                                             The Barberry Family–Berberidaceae

Mahonia nervosa (Pursh) Nutt.

Mahonia nervosa woodland(Ma-HOE-nee-uh  nerv-OH-suh)

Names: Low Oregon Grape is also called Cascade Oregon Grape, Cascade Barberry, Dull Oregon Grape, Dwarf Oregon Grape or Longleaf Mahonia.  Nervosa refers to the fan-like veins in its leaves. It is called “dull” because its leaves are not as shiny as Tall Oregon Grape’s leaves and “long-leaf” because it has more leaflets making a longer compound leaf.

 

Low Oregon GrapeThis shorter species is referred to as Low Oregon Grape to distinguish it from Tall Oregon Grape, Mahonia aquifolium.  It is also known as Berberis nervosa. Some botanists have argued that the genus Mahonia is not different enough from the genus Berberis to warrant its own genus. Mahonia is named after American Horticulturist, Bernard McMahon.  Horticulturists have consistently continued to use the genus Mahonia to refer to those species with compound leaves that give them a very different appearance from barberries.

Distribution of Low Oregon Grape from USDA Plants Database

Distribution of Low Oregon Grape from USDA Plants Database

Relationships: There are about seventy species of Mahonia in Asia, and Central and North America, about 13 in North America.  Three are found in the Pacific Northwest. Some cultivated varieties have been developed.

Distribution: It is found from southern British Columbia to central California, mostly west of the Cascade and Sierra Mountains; but it also occurs in northeastern Oregon and Washington and the Idaho panhandle.

Growth: Low Oregon Grape usually grows slowly to about 2 ft. (60cm), but may grow taller, especially in deeper shade.  It forms clumps, spreading by underground rhizomes to about 3 ft (1m) wide.

 

Habitat: It grows in dry to fairly moist, open to dappled, shady woods.

Mahonia nervosa flowersDiagnostic Characters: Mahonia nervosa is the easiest to distinguish from other native Mahonias; it has more leaflets, (9-19 per leaf) per ~12-inch (30cm) long leaf.  Leaves are clustered toward the tip of the stem in a terminal “rosette.”  Otherwise it is very similar to other Oregon Grapes with its spiny, leathery, often bronzy, compound leaves, bright yellow flowers and blue berries.

In the landscape, Low Oregon Grape is an excellent choice for dry shade.  With its leathery, fern-like, leaves, it is an attractive groundcover or border plant for a shady woodland garden. Its prickly leaves make it useful for a low barrier.  Sprays of golden-yellow flowers brighten gloomy, rainy spring days.  Flowers are followed by large clusters of blue berries with a waxy, whitish bloom.

Mahonia nervosa berriesPhenology:  Bloom Period:  April-May.  Fruits ripen August-September.

Propagation:  Seed is best sown as soon as it is ripe in a cold frame; seeds should not be allowed to dry out.  Stored seed requires a stratification period of at least 3 weeks.  Cuttings are best taken September-March, treated with hormone, and stuck in peat/perlite media; leaving only 1 or 2 leaflets and wounding the base of the cutting.  Applying bottom heat is also beneficial.  Layering and division are also possible.

Low Oregon Grape berries

 

Use by people: The tart berries were eaten by natives, but not in quantity; they were more often mixed with sweeter berries such as salal.  Today they are more frequently used in jelly or wine.  The yellow roots were used for dying basket materials; especially Beargrass.  The roots were also boiled to make a medicinal tea.

Use by wildlife: In some areas, Low Oregon Grape is browsed by Black-tailed Deer and Roosevelt Elk.  Many small mammals also eat the foliage, especially the White-footed Vole.  The fruits are eaten by many small birds and mammals.  The nectar of the flowers are favored by Anna’s Hummingbirds.  The plant provides cover for small birds and mammals.

Links:

USDA Plants Database

Consortium of Pacific Northwest Herbaria

WTU Herbarium Image Collection, Plants of Washington, Burke Museum

E-Flora BC, Electronic Atlas of the Flora of British Columbia

Jepson Eflora, University of California

Calphotos

Ladybird Johnson Wildflower Center

USDA Forest Service-Fire Effects Information System

Virginia Tech ID Fact Sheet

Plants for a Future Database

Native American Ethnobotany, University of Michigan, Dearborn


Tall Oregon Grape, Mahonia aquifolium

Tall Oregon Grape    The Barberry Family–Berberidaceae

Mahonia aquifolium plantMahonia aquifolium (Pursh) Nutt.

(Ma-HOE-nee-uh  ak-wih-FOAL-ee-um)

Names: Oregon Grapes have leaflets with sharp spines along their margin.  Because of this feature they are often confused with holly.  In fact, the species gets its name from the name for English Holly, Ilex aquifolium.  Aquifolium literally means leaves that have curved hooks like an eagle’s beak (aquiline is similarly derived).  Other common names include Oregon Grape-Holly, Holly-leaved Barberry, Holly-leaved Oregon Grape, Oregon Hollygrape and Mountain Grape.  It is the state flower of Oregon.

Tall Oregon Grape

 

This species is referred to as Tall Oregon Grape only to distinguish it from Low Oregon Grape, Mahonia nervosa.  Mahonia aquifolium is also known as Berberis aquifolium.  Some botanists argue that the genus Mahonia is not different enough from the genus Berberis to warrant its own genus. Mahonia is named after American Horticulturist, Bernard McMahon.  Horticulturists have consistently continued to use the genus Mahonia to refer to those species with compound leaves that give them a very different appearance from barberries.

 

Relationships: There are about seventy species of Mahonia in Asia, and Central and North America, about 13 in North America.  Some cultivated varieties have been developed.  Low Oregon Grape, Mahonia nervosa, is another common Oregon Grape in our region. Creeping Oregon Grape, Mahonia repens, is chiefly an east of the Cascades species. Mahonias easily hybridize; intermediate forms often appear.

Distribution of Tall Oregon Grape from USDA Plants Database

Distribution of Tall Oregon Grape from USDA Plants Database

Distribution: Tall Oregon Grape is native along the Pacific Coast from southern British Columbia to Northern California.  Its range stretches across eastern Washington to the Idaho panhandle and Western Montana.  It also has been found growing in the Eastern United States, mostly in the Great Lakes Region.  Having long been valued as an ornamental shrub, it may have been introduced to some of those other areas.

Growth: Tall Oregon Grape grows to about 6-8 feet (2-2.5m) tall and spreads by underground stems to about 5 feet (1.5m) wide.  It may grow slowly at first as it becomes established, then will quickly grow to its mature size.

Habitat: Tall Oregon Grape is usually found on somewhat dry, rocky, open sites.  It is often found along roadsides; in fact it is a preferred native for new plantings along major highways.

Tall Oregon Grape has 5-9 shiny leaflets per leaf.

Tall Oregon Grape has 5-9 shiny leaflets per leaf.

Diagnostic Characters: All Mahonias have compound leaves.  Tall Oregon Grape has 5-9 leaflets per leaf with one central vein per leaflet.  The leaves are generally shinier that those of Low or Creeping Oregon Grape. New growth in the spring is usually a bronzy red.  Cold weather in the winter often causes leaves to turn purplish or bronze.  Yellow flowers are borne in erect terminal clusters.  Dark blue, grape-like berries are about 1 cm across with a silvery bloom.

Oregon Grape shrub

 

In the Landscape: Tall Oregon Grape has long been recognized as an outstanding landscaping choice.  It can be used as an accent plant or as a screen.  Its bronzy foliage, bright yellow, lightly scented flowers and bold texture can make an attractive addition to any landscape, but because of its prickly nature it should not be planted along walkways, where people may inadvertently brush up against it.  Old or disfigured stems can be pruned all the way to the ground.Oregon Grape flowers

Phenology:  Bloom Period:  April-May. Fruits ripen September-October.

Propagation:  Seeds should be stratified for 90 days at 40º*F. (4ºC) or planted outside as soon as they are ripe– seeds should not be allowed to dry out. Cuttings should be taken in late fall and treated with hormone.  Suckers from large plants may also be replanted.

Oregon Grape berries make great jelly!

Oregon Grape berries make great jelly!

 

 

Use by people: Some natives ate the sour berries fresh.  The juice has a lot of natural pectin and is great made into jelly or wine, by itself or in combination with other berries such as Salal.  The roots of all Mahonias are bright yellow and were often used for making dye, especially for baskets.

Use by wildlife: Birds eat the berries of Oregon Grape.  The foliage provides cover for many species and browse for deer.  The flowers are very attractive to insect pollinators and hummingbirds.

 

Links:

USDA Plants Database

Consortium of Pacific Northwest Herbaria

WTU Herbarium Image Collection, Plants of Washington, Burke Museum

E-Flora BC, Electronic Atlas of the Flora of British Columbia

Jepson Eflora, University of California

Calphotos

Ladybird Johnson Wildflower Center

Virginia Tech ID Fact Sheet

Native Plants Network, Propagation Protocol Database

Plants for a Future Database

Native American Ethnobotany, University of Michigan, Dearborn

 

*Creeping Oregon Grape

Mahonia repens in pots

Mahonia repens (Lindl.) G. Don

Creeping Oregon Grape or Creeping Mahonia is another valuable landscape shrub/groundcover.  Some consider it a variety of Tall Oregon Grape. It does hybridize easily and intermediate forms can be found. It is native to much of the western United States, but grows mostly east of the Cascades from Central BC southward, only reaching the coast in southern Oregon and northern California.  It is a good as a groundcover that grows only 1 to 2 ft. (30-60cm) tall, spreading by underground rhizomes; in full sun or partial shade.

Links:

USDA Plants Database

Consortium of Pacific Northwest Herbaria

WTU Herbarium Image Collection, Plants of Washington, Burke Museum

E-Flora BC, Electronic Atlas of the Flora of British Columbia

Jepson Eflora, University of CaliforniaMahonia repens

Calphotos

Ladybird Johnson Wildflower Center

USDA Forest Service-Fire Effects Information System

Virginia Tech ID Fact Sheet

Native Plants Network, Propagation Protocol Database

Plants for a Future Database

Native American Ethnobotany, University of Michigan, Dearborn

Oregon Ash, Fraxinus latifolia

Oregon Ash                                                                                        The Olive Family–Oleaceae

Fraxinus latifolia treeFraxinus latifolia Benth.

(FRAKS-ih-nus lat-ih-FOAL-ee-uh)

Names: Latifolia means “wide leaves.”  Oregon Ash has wider leaflets than most Ashes.

Relationships: There are about 65 species of Ashes, mostly in the temperate regions of the northern hemisphere.  About 16 species occur in North America.

Distribution of Oregon Ash from USGS ( “Atlas of United States Trees” by Elbert L. Little, Jr. )

Distribution of Oregon Ash from USGS ( “Atlas of United States Trees” by Elbert L. Little, Jr. )

Distribution: Oregon Ash is found from the southern coast of British Columbia, west of the Cascades in Washington and Oregon, to the coast ranges and Sierra Nevadas of California.

Young Oregon Ash tree.

Young Oregon Ash tree.

Growth: Oregon Ash grows to about 75 feet (25m).  It grows quickly for the first 80 years, then more slowly—living to about 250 years.

Habitat: This tree grows in moist to wet soils near streams, lakes and in flood plains.

 

Oregon Ash typically grows on lakesides and in floodplains,

Oregon Ash typically grows on lakesides and in floodplains,

Wetland Designation: FACW, Facultative wetland, it usually occurs in wetlands but occasionally occurs in non-wetlands.

Flowers are very small.

Flowers are very small.

Fraxinus latifolia leaves

 

 

 

 

 

 

 

Diagnostic Characters: Oregon Ash is our only tree with compound leaves, making it easy to identify.  The oppositely arranged, pinnately compound leaves have 5-7 leaflets.  Flowers are small and inconspicuous, appearing before the leaves.  The seeds are single samaras, like a half of a maple seed, with long (3-5cm) wings, borne in large, drooping clusters.

Single samaras of Oregon Ash.

Single samaras of Oregon Ash.

 

In the Landscape: Oregon Ash is perhaps my least favorite of our native trees.  The new growth is susceptible to aphids.  It is, however, useful for revegetating wet areas that are flooded periodically.  Autumn is its most aesthetic season, when female trees produce attractive seed clusters, followed by bright yellow fall foliage.

Phenology: Bloom Period: March-May. Samaras ripen: August-September.

Propagation: Seeds are best collected slightly green before fully dry on the tree and sown immediately outside or in a cold frame.   Otherwise they require a cool, moist stratification at 40ºF (4ºC) for 90 days.

Use by people: Natives used Oregon Ash wood for canoe paddles and digging sticks. Today the hard wood is used for tool handles, furniture, sports equipment, and barrels.  It also makes good firewood.

Use by wildlife: The winged seeds of Oregon Ash are eaten by a birds and small mammals.  The foliage is food for butterfly larvae and may be consumed by passing browsers.

Links:

USDA Plants Database

Natural Resources Canada

Consortium of Pacific Northwest Herbaria

WTU Herbarium Image Collection, Plants of Washington, Burke Museum

E-Flora BC, Electronic Atlas of the Flora of British Columbia

Jepson Eflora, University of California

Calphotos

Ladybird Johnson Wildflower Center

Silvics of North America

Virginia Tech ID Fact Sheet

Plants for a Future Database

Native American Ethnobotany, University of Michigan, Dearborn

National Register of Big Trees

 

Douglas Maple, Acer glabrum var. douglasii

Douglas Maple LeavesDouglas Maple

 Acer glabrum var. douglasii (Hook.)Dippel

(AY-ser GLAB-rum)

Names: Acer glabrum is better known as Rocky Mountain Maple in the interior regions of the country.   Glabrum means smooth, without hair, referring to its smooth stems and leaves. The variety is named after David Douglas,

Relationships: There are nearly 150 species of maples worldwide.  Most are from eastern Asia.  North America is home to about a dozen.  Maples are popular ornamental trees and there are many cultivated varieties.  We have three native maple species in the Pacific Northwest:  Big-Leaf Maple and two more shrubby cousins, Vine Maple, Acer circinatum, and Douglas Maple, Acer glabrum.

Distribution of Rocky Mountain Maple from USGS ( “Atlas of United States Trees” by Elbert L. Little, Jr. )

Distribution of Rocky Mountain Maple from USGS ( “Atlas of United States Trees” by Elbert L. Little, Jr. )

Distribution: The variety douglasii, is found from coastal southeast Alaska and British Columbia, to southern Oregon; east to Idaho and Montana.

Growth:  It is a small tree or shrub to 30 ft. (10m), usually multi-stemmed.

Habitat: Douglas Maple will withstand drier, more open sites than Vine Maple and will also withstand colder temperatures. Wetland designation: FAC, Facultative, it is equally likely to occur in wetlands or non-wetlands.

Douglas Maple LeafDiagnostic Characters: The toothed leaves of Douglas Maple are 3-5 lobed, 1-3 in. (2-8cm) wide.  Young twigs are usually reddish, in contrast to Vine Maple’s green stems.  The flowers are greenish-yellow.  The samaras are about 1 in (2-3cm) long in a V-shape.

In the landscape: Douglas Maple can be used in the same way as Vine Maple.  Fall foliage ranges from yellow to orange to crimson.

Double samaras of Douglas Maple

Double samaras of Douglas Maple

Propagation:  Seeds do not store well. They are best sown as soon as they are ripe outside or in a cold frame.  Germination occurs in late winter or spring.  The seeds may also be scarified or soaked for 24 hours, then cold stratified at 40ºF (4ºC) for 2-6 months.  Seeds and seedlings need to be protected from rodents, slugs and other herbivores.  Lower branches may be layered to generate rooted cuttings

Use by natives: Natives used Douglas Maple for snowshoe frames.

Use by wildlife: It is an important browse species for deer, elk and other big game animals.  Grosbeaks and small mammals eat the seeds.

 

Links:

USDA Plants Database

Natural Resources Canada

Consortium of Pacific Northwest Herbaria

WTU Herbarium Image Collection, Plants of Washington, Burke Museum

E-Flora BC, Electronic Atlas of the Flora of British Columbia

Jepson Eflora, University of California

Calphotos

Ladybird Johnson Wildflower Center

USDA Forest Service-Fire Effects Information System

Virginia Tech ID Fact Sheet

Native Plants Network, Propagation Protocol Database

Plants for a Future Database

Native American Ethnobotany, University of Michigan, Dearborn

National Register of Big Trees

 

Vine Maple, Acer circinatum

Vine Maple                                                   The Maple Family–Aceraceae

 Vine Maple largeAcer circinatum Pursh.

(Ay-ser Ser-sin-AY-tum)

Names: “Vine” Maple, although not really a vine, has very slender, often sprawling, branches. These branches often root to produce new trees, creating dense thickets underneath the shade of taller conifers.  It is a small, usually multi-stemmed tree or shrub.  Circinatum refers to the “rounded,” regularly lobed leaves.

Relationships: There are nearly 150 species of maples worldwide.  Most are from eastern Asia.  North America is home to about a dozen.  Maples are popular ornamental trees and there are many cultivated varieties.  We have three native maple species in the Pacific Northwest:  Big-Leaf Maple and two more shrubby cousins, Vine Maple, Acer circinatum, and Douglas Maple, Acer glabrum

Distribution of Vine Maple from USGS ( “Atlas of United States Trees” by Elbert L. Little, Jr. )

Distribution of Vine Maple from USGS ( “Atlas of United States Trees” by Elbert L. Little, Jr. )

Distribution:  It is found from Alaska and British Columbia to northern California, from the east side of the Cascade Mountains to the Pacific coast.

Vine Maple often grows as an understory tree/shrub.

Vine Maple often grows as an understory tree/shrub.

Growth: Vine maple grows to 21 feet (7m) and lives about 80 or 90 years.

Habitat: Although in nature, Vine Maple is often found in moist to wet places in the shade of other trees, it will also thrive in sunny openings with adequate moisture.

Wetland designation: FAC-, Facultative, it is equally likely to occur in wetlands or non-wetlands.

 

White flowers with red sepals.

White flowers with red sepals.

Diagnostic Characters: Like all maples, the leaves are arranged opposite each other on the stem.  Vine maple leaves have a very distinctive shape.  Its symmetric, palmate leaves have 7-9 regularly spaced lobes, all nearly the same length.  Young stems are a pale green.  White flowers with wine colored sepals are replaced by widely spreading samaras– the paired, winged seeds almost forming a straight line.

Vine Maples have distinctive rounded, evenly lobed leaves.

Vine Maples have distinctive rounded, evenly lobed leaves.

 

 

 

 

 

 


Vine Maple shrubIn the Landscape: Vine Maple is one of the most popular native shrubs for landscapes.  An enchanting woodland landscape may be created by planting large groupings under the shade of taller trees along with ferns and woodland flowers.  Vine Maple is also a good choice next to buildings and in parking lots.  There is some variability in the fall color display.  Those growing in shade tend to turn a pale yellow; those growing in sun are more likely to turn orange or scarlet.

 

Vine Maple landscape

 

Plants growing in the sun often have redder fall color.

Plants growing in the sun often have redder fall color.

 

 

 

 

 

 

 

Double samaras of vine maple

Double samaras of vine maple

Phenology: Bloom Period:  April-June. Double samaras ripen September to October and are dispersed through November.

Propagation:  Vine Maple seeds do not store well. They are best sown as soon as they are ripe outside or in a cold frame.  Germination occurs in late winter or spring.  The seeds may also be scarified or soaked for 24 hours, then cold stratified at 40ºF (4ºC) for 2-6 months.  Seeds and seedlings need to be protected from rodents, slugs and other herbivores.  Lower branches may be layered to generate rooted cuttings.

 

 

Use by People: Natives used Vine Maple branches for baskets and fish traps.  It was often used for firewood.

Use by wildlife: Summer foliage is a preferred food for deer and elk.  Seeds, buds and flowers provide food for many birds and rodents.  Squirrels and chipmunks will cache the seeds.  In fact, if you try to collect seeds, you may discover that many of the samaras have already had the seed removed!

Links:

USDA Plants Database

Natural Resources Canada

Consortium of Pacific Northwest Herbaria

WTU Herbarium Image Collection, Plants of Washington, Burke Museum

E-Flora BC, Electronic Atlas of the Flora of British Columbia

Jepson Eflora, University of California

Calphotos

Ladybird Johnson Wildflower Center

USDA Forest Service-Fire Effects Information System

Virginia Tech ID Fact Sheet

Native Plants Network, Propagation Protocol Database

Plants for a Future Database

Native American Ethnobotany, University of Michigan, Dearborn

National Register of Big Trees