Monthly Archives: March 2015

Black Hawthorns, Crataegus douglasii & C. suksdorfii

                                                                                                  The Rose family–Rosaceae

Douglas Hawthorn

Crataegus douglasii flowers have 10 stamens.

Crataegus douglasii flowers have 10 stamens.

Crataegus douglasii Lindl. (var. douglasii)

(kra-TEE-gus doug-LASS-ee-eye)

Suksdorf’s Hawthorn

 Crataegus suksdorfii  (Sarg.) Kruschke

(kra-TEE-gus sooks-DORF-ee-eye)

Names: Mayflower is the name given to Hawthorns in the spring. Douglas Hawthorn is also known as Black Hawthorn, Black Hawberry, Western Thornapple or similar variations thereof.  Suksdorf’s Hawthorn was previously considered a variety of Douglas Hawthorn (C. douglasii var. suksdorfii).  Both can be considered Black Hawthorns due to their black fruits. They are very similar and differ mostly in the number of chromosomes in each cell and the number of stamens within each flower.  The tetraploid Douglas Hawthorn has 10 stamens. The diploid Suksdorf’s Hawthorn has 20 stamens.  Because of the level of polyploidy in each of these species, Suksdorf’s Hawthorn is believed to be a parent of Douglas Hawthorn either through hybridization with another species or by doubling its own chromosome number. It is also known as Crataegus gaylussacia.

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

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

Relationships: There are hundreds of hawthorn species in North America, Europe and Asia.  The exact number is difficult to determine because natural hybridization and polyploidy make it very challenging to classify species within this genus.  Red Hawthorn, C. columbiana, which may be seen in some areas of the B.C. coast, is now either lumped in C. douglasii or C. chrysocarpa  var. piperi.  Oneseed Hawthorn, C. monogyna, is an introduced species, commonly found in the Pacific Northwest.

Distribution of Suksdorf Hawthorn from USDA--note it only occurs in the SW corner of BC. It is unclear if it still is present in SE Alaska.

Distribution of Suksdorf Hawthorn from USDA–note it only occurs in the SW corner of BC. It is unclear if it still is present in SE Alaska.

Distribution: Douglas Hawthorn is the most widespread member of its genus.  It is found from southern Alaska to northern California in the west, and eastward across the northern United States and Canada in disjunctive populations to the Great Lakes region in the northeast.  Suksdorf’s Hawthorn is found in all the Pacific Coast states including Idaho and Montana.  Both species have been observed growing together in eastern Oregon, eastern Washington, Idaho and the San Juan Islands.

Growth: Black Hawthorns grow 20-45 feet (7-15m) tall.

Habitat: Both grow in moist sites in open areas, forest edges and along streams.  Douglas Hawthorn can tolerate drier sites.

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

Black Hawthorn Fruit

Black Hawthorn Fruit

Diagnostic Characters: Black Hawthorns have sharp thorns, about 3 cm long.  Their leaves are thick and leathery with 5-9 lobes only at the top.  White, stinky flowers are borne in clusters.  Fruits are purplish black, apple-like, about 1 cm long.

In the Landscape: Cultivated European species are grown for their attractive flowers and fruits.  Black Hawthorns are good for restoration because their spreading roots hold soil and resist erosion.  They also spread readily by root suckers.  Planted as a hedge, Hawthorns can create an impenetrable, thorny thicket.

Phenology: Bloom Period:  May-June.  Fruits are dispersed mid-July through August.

Propagation: Black Hawthorn seed is best sown fresh outside in the fall.  Some seeds may germinate in the spring, but most will take another year.  Scarification in acid followed by a 3-month warm stratification at 60ºF (15ºC) and then a 3 month cold stratification at 40ºF (4ºC) may hasten germination.  Black Hawthorn root suckers can also be transplanted.

Use by People: The thorns from Black Hawthorn were used by natives for rake tines, lances and fishhooks.  The hard wood was made into tool handles and weapons.  The fruit was eaten both fresh and dried, but was not a favorite food.

Black Hawthorns create an impenetrable hedge which is great for sheltering small birds and mammals.

Black Hawthorns create an impenetrable hedge which is great for sheltering small birds and mammals.

Use by Wildlife: The thickets created by Black Hawthorn are excellent habitat for wildlife, providing cover and nesting sites.  The fruit is consumed by birds, such as Cedar Waxwings, and many types of mammals, but just as for native people, it is not a favorite food for most species of wildlife.

Links for Crataegus douglasii:

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 Manual, 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

Links for Crataegus suksdorfii:

USDA Plants Database

Consortium of Pacific Northwest Herbaria

WTU Herbarium Image Collection, Plants of Washington, Burke Museum

Jepson Manual, University of California

Calphotos

National Register of Big Trees

Bitter Cherry, Prunus emarginata

Bitter Cherry                                                                                       The Rose family–Rosaceae

 Prunus emarginata   (Douglas ex Hook.) D.Dietr.

(PROO-nus ee-marj-ih-NATE-uh)Prunus emarginata fall

Names: As the common name suggests, the fruits of Bitter Cherry are very bitter.  The fruit is inedible to people.  Emarginate means notched at the margins, usually at the tip of a leaf or petal.  I am not sure what this refers to in this species, perhaps just that the leaves are toothed or rounded at the tip.

Relationships: The genus, Prunus, contains cherries, plums, peaches, apricots, and almonds.  There are about 30 species native to North America, but many, many species and cultivated varieties have been introduced.  Most cultivated cherries and plums are from Europe; many ornamental varieties are from China and Japan.

Distribution of Bitter Cherry from USGS ( “Atlas of United States Trees” by Elbert L. Little, Jr.

Distribution of Bitter Cherry from USGS ( “Atlas of United States Trees” by Elbert L. Little, Jr.

Distribution: Bitter Cherry is found from southern British Columbia to southern California along the coast through the Cascades and Sierra Nevadas; east to the Rocky Mountains of Idaho and Montana, and in isolated communities in Wyoming, Utah, Arizona and New Mexico.

Young Bitter Cherry with attractive bark.

Young Bitter Cherry with attractive bark.

Growth: Bitter Cherry grows quickly to 6 to 45 feet (2-15m) tall.  It is not long-lived, perhaps only living about 30-40 years.

Habitat:  Bitter Cherry trees may be found in moist, second growth forests, often along streams.

Wetland designation: FACU, Facultative upland, usually occurs in non-wetland but is occasionally found in wetlands.

Bitter Cherry flowers and leavesDiagnostic Characters: In older trees, Bitter Cherry is most easily identified by its reddish brown, or gray bark with horizontal lenticels (raised pores that allow for gas exchange through the bark).  The leaves are small, (3-8cm), finely toothed and rounded at the tip.  The flowers are white or pinkish in a flat-topped cluster.  Bitter Cherry fruits are bright red, about 1 cm in diameter.  Chokecherry, P. virginiana, a species that is common on the east side of the Cascades, has long, narrow flower clusters and darker, purple to black cherries.

Prunus emarginata treeIn the Landscape: With its attractive bark, flowers and fruit, Bitter Cherry is a pleasing addition to a woodland garden.

Phenology: Bloom Period:  April-June. Cherries ripen July to September, dispersal occurs August through September.

Bright Red Fruit of Bitter Cherry.

Bright Red Fruit of Bitter Cherry.

Propagation:  Bitter Cherry is usually propagated using fresh seed.  A cool, moist stratification at 40ºF (4ºC) for 3 months is necessary to break the embryo’s dormancy.  Seeds may take18 months to germinate; in fact, Bitter Cherry seeds may remain viable in the soil for many years.  Bitter Cherry may also be propagated by softwood taken in spring or early summer, or heel cuttings of semi-hardwood in late summer.

Bark has horizontal lenticels, typical of many cherries.

Bark has horizontal lenticels, typical of many cherries.

Use by People: Natives used cherry bark as decoration in their basket designs.  It was also used for wrapping the joints of many implements, such as spears, arrows and fire drills.

Use by Wildlife: Bitter Cherry is browsed by deer, elk and black bear.  Birds, small mammals and slugs eat the cherries.

Two other Prunus species are found in some parts of our region.  Chokecherry, P. virginiana, although more common on the east side of the Cascades, is found in some parts of the west side, more often in drier, prairie habitats.  It has elongated flower clusters and dark purple to black fruits.  Klamath Plum, P. subcordata, is rare in the Willamette Valley, more common in southern Oregon and the Sierras of California.

  •    The popular evergreen hedge, English Laurel, Prunus laurocerasus, is also in this genus.  It has been overplanted in much of the northwest.  Many people do not realize that it is really a tree that can grow to 45 feet (15m) or more.  It often quickly outgrows its intended location such that even with multiple shearings, it can become too large to handle.  Even more troubling is that birds will carry its seeds to pristine forests, where it will germinate and invade native habitats.  Better choices for evergreen hedges include: Pacific Wax Myrtle, Myrica californica or California Bay Laurel, Umbellularia californica.
  •  You may also see cherry trees that have escaped cultivation growing in seemingly wild habitats, (Sweet Cherry, P. avium, a native of Eurasia and north Africa is the most likely renegade.)

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 Manual, 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