Arbutus menziesii

Pacific madrone
Conservation status
Least Concern (IUCN 3.1)[1]
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Asterids
Order:	Ericales
Family:	Ericaceae
Genus:	Arbutus
Species:	A. menziesii
Binomial name
Arbutus menziesii Pursh[2]
Natural range of Arbutus menziesii
Synonyms[3]
Arbutus menziesii var. elliptica DC. Arbutus menziesii var. oblongifolia DC. Arbutus procera Douglas ex Lindl. 1836 not Sol. ex DC. 1839

Arbutus menziesii or Pacific madrone (commonly madrona in the United States and arbutus in Canada), is a species of broadleaf evergreen tree in the family Ericaceae, native to the western coastal areas of North America, from British Columbia to California.

Its waxy evergreen foliage, contorted growth habit, and distinctive flaky bark make it a striking sight in the coastal cliffs and hills where it is abundant.

Common names[]

In Canada, it is simply referred to as arbutus. It is known in the United States as the madrona,^[4] madrone, madroño, madroña, or bearberry. The name strawberry tree (A. unedo) may also be found in relation to A. menziesii (though it has no relation to the strawberry fruit). According to the Sunset Western Garden Book, in the United States, the name "madrone" is more common south of the Siskiyou Mountains of southern Oregon and Northern California and the name "madrona" is more common north of the Siskiyous. The Concow tribe calls the tree dis-tā'-tsi (Konkow language) or kou-wät′-chu.^[5] Its species name was given it in honor of the Scottish naturalist Archibald Menzies, who noted it during George Vancouver's voyage of exploration.^[6][7]

Description[]

Arbutus menziesii is an evergreen tree with rich orange-red bark that when mature naturally peels away in thin sheets, leaving a greenish, silvery appearance that has a satin sheen and smoothness.^[8] In spring, it bears sprays of small bell-like flowers, and in autumn, red berries.^[8] The berries dry up and have hooked barbs that latch onto larger animals for migration. It is common to see madronas of about 10 to 25 metres (33 to 82 ft) in height, but with the right conditions trees may reach up to 30 metres (98 ft). In ideal conditions, madronas can also reach a thickness of 5 to 8 feet (1.5 to 2.4 m) at the trunk, much like an oak tree.^{[citation needed]} Leaves are thick with a waxy texture, oval, 7 to 15 centimetres (2.8 to 5.9 in) long and 4 to 8 centimetres (1.6 to 3.1 in) broad, arranged spirally; they are glossy dark green above and a lighter, more grayish green beneath, with an entire margin. The leaves are evergreen, lasting a few years before detaching, but in the north of its range, wet winters often promote a brown to black leaf discoloration due to fungal infections.^[9][10] The stain lasts until the leaves naturally detach at the end of their lifespan.

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  Tree

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  Leaves

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  The peeling red papery bark is distinctive

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  In spring, it bears sprays of small, white, bell-shaped flowers.

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  Flower Buds

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  Fruit of Arbutus menziesii

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  An old specimen at Henry Cowell Redwoods State Park, with foliose lichens growing on it

Distribution and habitat[]

Madrones are native to the western coast of North America, from British Columbia (chiefly Vancouver Island and the Gulf Islands) to California. They are mainly found in Puget Sound, the Oregon Coast Range, and California Coast Ranges, but are also scattered on the west slope of the Sierra Nevada and Cascade mountain ranges. They are rare south of Santa Barbara County, with isolated stands south to Palomar Mountain in California.^[8] One author lists their southern range as extending as far as Baja California in Mexico,^[11] but others point out that there are no recorded specimens collected that far south,^[8] and the trees are absent from modern surveys of native trees there.^[12] However, other Arbutus species are endemic to the area.

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  Arbutus menziesii lignotuber near ground level provides fire-resistant storage of energy and sprouting buds if fire damage requires replacement of the trunk or limbs.

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  Tree growing in snow at Gowlland Tod Provincial Park, British Columbia

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  Trees growing with Pseudotsuga menziesii var. menziesii in Anacortes, Washington

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  Mature Trees at Deception Pass State Park

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  Mature tree at Big Basin Redwoods State Park, California

Cultivation[]

Arbutus menziesii from Curtis's Botanical Magazine, vol. 135 1909

The trees are difficult to transplant and a seedling should be set in its permanent spot while still small.^[10] Transplant mortality becomes significant once a madrone is more than 1 foot (30 cm) tall. The site should be sunny (south- or west-facing slopes are best), well drained, and lime-free (although occasionally a seedling will establish itself on a shell midden). In its native range, a tree needs no extra water or food once it has become established. Water and nitrogen fertilizer will boost its growth, but at the cost of making it more susceptible to disease.^{[citation needed]}

This plant has gained the Royal Horticultural Society's Award of Garden Merit.^[13]

Uses[]

Native Americans ate the berries raw and cooked, but because the berries have a high tannin content and are thus astringent, they more often chewed them or made them into a cider. Overeating causes cramps.^[14] Native Americans also use the berries to make necklaces and other decorations, and as bait for fishing. Bark and leaves were used to treat stomach aches, cramps, skin ailments, and sore throats. The bark was often made into a tea to be drunk for these medicinal purposes.^[15][16] The wood is durable and has a warm color after finishing, so it has become more popular as a flooring material, especially in the Pacific Northwest.^[17] An attractive veneer can also be made from the wood.^[18] However, because large pieces of madrona lumber warp severely and unpredictably during the drying process, they are not used much.^[7] Madrone is burned for firewood, though,^[15][19] since it is a very hard and dense wood that burns long and hot, surpassing even oak in this regard.

Ecology[]

Many mammal and bird species feed off the berries,^[20] including juncos, American robins, cedar waxwings, band-tailed pigeons, varied thrushes, quail, mule deer, raccoons, ring-tailed cats, and bears. As the fruit are produced in great quantity and may persist on the tree into winter, their value as a food source is great. Mule deer will also eat the young shoots when the trees are regenerating after fire.^[8][15] The flowers also produce nectar which can be made into honey.^[14] Mature leaves are almost always ignored by browsing animals, but young leafy sprouts are eaten by ungulates and the dusky-footed woodrat. It is considered a high-importance winter forage species for many ungulates. ^[21]

It is important as a nest site for many birds,^[15] and in mixed woodland it seems to be chosen for nestbuilding disproportionately to its numbers.^{[citation needed]} This may be due to the susceptibility of the tree to heart rot, which makes it desirable for cavity-nesting birds. Pacific Madrona also provides cover for big game and small mammals, and perching sites for a variety of bird species. They are important habitat for woodpecker and sapsucker species.^[21]

Pathogens[]

Arbutus menziesii has low disease resistance and hosts many pathogens such as heart rot, butt rot, and stem cankers. It is afflicted by a fungal leaf blister disease caused by Exobasidium vaccinii which causes mostly aesthetic damage. ^[21] The species is also lethally affected by fungi of the genus Phytophthora, including the Sudden Oak Death (Phytophthora ramorum) which damages branches and foliage, ^[8] and a canker disease caused by Phytophthora cactorum which leads to root and butt rot.^[21] Other pathogens include Arbutus canker (Nattrassia mangiferae), which causes shoot blight, and Fusicoccum aesculi which causes dieback and creates a burned appearance. Thinning stands, soil loss and compaction, and a host of other impacts increase susceptibility to disease, especially on less dense stands.^[21]

Conservation[]

Although drought tolerant and relatively fast growing, Arbutus menziesii is currently declining throughout most of its range. One likely cause is fire control; under natural conditions, the madrona depends on intermittent naturally occurring fires to reduce the conifer overstory.^[6][8][15] Mature trees survive fire, and can regenerate more rapidly after fire than the Douglas firs with which they are often associated. They also produce very large numbers of seeds, which sprout following fire.^[8]

Increasing development pressures in its native habitat have also contributed to a decline in the number of mature specimens. This tree is extremely sensitive to alteration of the grade or drainage near the root crown. Until about 1970, this phenomenon was not widely recognized on the west coast; thereafter, many local governments have addressed this issue by stringent restrictions on grading and drainage alterations when Arbutus menziesii trees are present.^{[citation needed]}

Invasive species such as Scotch broom and gorse are a threat to the Pacific madrona as they can invade natural areas and outcompete young saplings for space, light, nutrients, and water.^[21]

Largest specimen burned[]

During the Soberanes Fire in the summer of 2016, the largest known specimen of madrone was burned and possibly killed. The tree, 125 feet (38 m) tall and more than 25 feet (7.6 m) in circumference, was listed on the American Forests National Big Tree list, a register of the biggest trees by species in the United States. The tree was located within the Joshua Creek Canyon Ecological Reserve on the Big Sur Coast of California.^[22] The fire was caused by an illegal campfire.^[23]

References[]

Works cited[]

• Chesnut, Victor King (January 24, 1902). Plants used by the Indians of Mendocino County, California. Washington, D.C.: Government Printing Office. Retrieved August 24, 2012.
• Metcalf, Woodbridge (1959). Native Trees of the San Francisco Bay Region. Berkeley, California: University of California Press. ISBN 0520008537. OCLC 2631060.
• Niemiec, Stanley S.; Ahrens, Glenn R.; Hibbs, David E. (March 1995). "Hardwoods of the Pacific Northwest" (PDF). Oregon State University. Retrieved May 25, 2013.

External links[]

Wikimedia Commons has media related to: Arbutus menziesii (category)

• Jepson Flora Project: Arbutus menziesii
• The BC Ministry of Forests and Range Tree Book on Arbutus