Cercocarpus montanus

Taxonomy: Rosaceae (rose family)

Common names: mountain mahogany, true mountain mahogany, alderleaf mahogany, palo duro

By: Bonnie Parham, Rondus Chee, and DeAnn Spiros (Summer 2002)

Description Habitat Nutrition Medicinal Uses

Other Uses and Values Toxic property Palo duro

Varieties of Mountain Mahogany Chemical Structures References

Mountain Mahogany

Scientific name: Cercocarpus montanus

Plant family: Rosaceae

Plant Type: Deciduous shrub

Cercocarpus - Greek for "shuttle-fruit" or "tailed fruit," referring to the long tail

montanus - of the mountains

Varieties of mountain mahogany:

C. montanus var. argenteus

Silver mountain mahogany

C. montanus var. blancheae

Island mountain mahogany

C. montanus var. flabellifolius

C. montanus var. glaber

Birchleaf mountain mahogany

C. montanus var. macrourus

Klamath mountain mahogany

C. montanus var. minutiflorus

Smooth mountain mahogany

C. montanus var. montanus Raf.

True mountain mahogany or

Alderleaf mountain mahogany

C. montanus var. paucidentatus

Hairy mountain mahogany

True or Alderleaf Mountain Mahogany

Description

True or alderleaf mountain mahogany is a shrub or small tree that can grow to be 7 to 20 feet high. The stems are reddish brown and as they age they turn pale gray. Mountain mahogany has leaves that are dark green on top with a fuzzy silver underside. The leaves are thick, fuzzy, and clustered and somewhat resemble birch leaves.

Flowers of the mountain mahogany can be whitish-pink, red, or yellow. They also have silver-white fruits and curling, feathery “tails” as they wither. The flowers are not very showy but they do have a very pleasant, sweet smell. The bloom period is from May through November. Mountain mahogany has brown seeds which are dispersed in the air on the feathery plumes.

The roots of the mountain mahogany plant are strong, lateral, and come from a large root crown. They descend to depths of 3.3 feet or more. The average root depth found in north central New Mexico was 3.7 feet. The maximum root depth was between 4 and 5.6 feet and this was found near Colorado Springs. The roots of the true or alderleaf mountain mahogany may have associations of nitrogen-fixing endomycorrhizae.

True mountain mahogany is in all probability a long-living plant. In Utah, some true mountain mahogany was found to be 54 years old. True mountain mahogany exhibits relatively low initial growth rates and seedling heartiness. The plant can be seeded or transplanted and the seeds can be stored for a number of years.

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Habitat

True or alderleaf mountain mahogany commonly grows on plains, foothills, rocky slopes,

ridges, ledges, and bluffs. It grows between elevations of 4,000 and 8,000 feet, but typically

between 6,000 and 8,000 feet. Mountain mahogany commonly grows in coarse, shallow,

well-drained residual soils in sunny areas, and it sometimes grows in the moist, fertile,

relatively deep soil of canyon bottoms.

Distribution:

True or alderleaf mountain mahogany grows in the following states:

· Arizona

· California

· Idaho

· South Dakota

· New Mexico

· Oklahoma

· Texas

· Kansas

· Nebraska

· Oregon

· Montana

· Nevada

· Utah

· Wyoming

· Colorado

Nutrition

Mountain mahogany is considered nutritious to foraging animals because the mineral levels compare favorably with those of other forage plants. According

to the U.S. Department of Agriculture, Fire Sciences Laboratory, June 2002 report, “True mountain mahogany has a desired calcium to phosphorus ratio of

7.5:1. Summer foliage in Colorado was found to have 11.2% to 16.3% crude protein and 33.4% to 38.7% digestible organic matter. The true mountain

mahogany leaves and twigs collected in Utah contained the following mineral concentrations in parts per million:

Zn 34.2 Cu 28.9

Mn 12.0 Fe 166.4

Ca 5486.0 Mg 2632.0

Na 386.6 P 731.8

N 9048.0

True mountain mahogany has low manganese, iron, potassium, and phosphorus when compared to its associates. Copper concentration is relatively high;

browsing animals would be poisoned by copper toxicity if true mountain mahogany were their sole diet item.”

U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (2002, June). Fire Effects Information System, [Online].

Available: http://www.fs.fed.us/database/feis/ [Parham, June 23, 2002].

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Medicinal Uses

The root of the alderleaf or true mountain mahogany plant is considered one of the Navajo Indian’s life medicines. Because of the emetic properties,

the Navajos use the root and leaves of the plant to treat stomach problems. It is also given to new mothers to speed recovery after giving birth.

Mountain mahogany has some ceremonial uses as well. It is used to make ceremonial equipment and medicine. It is used as an emetic in 5 and 9

night ceremonies.

Other Uses and Values

Alderleaf or true mountain mahogany is used for household items. Its hard wood is perfect for tool handles, weaving forks, and battens. It was used for fire sticks, throwing sticks, and prayer sticks. It is also recorded that the hard wood was occasionally carved for arrow points.

The Spanish New Mexicans used the mountain mahogany to keep bedbugs away. They would hang the leaf twigs around their bed or dry them and put them in little pouches and place them under their mattress. Mountain mahogany is also used as an early dye. The roots and bark produce a reddish-brown dye for use on leather and baskets,

Mountain mahogany is also an excellent forage plant for sheep, deer, elk, and antelope. In fact, hunters chew the leaves from mountain mahogany browsed by deer for good luck in hunting.

Another use for true mountain mahogany is in landscaping. It is a very heat and drought tolerant plant and it can be used for water-efficient landscaping in dry environments. It is planted as an ornamental plant throughout the Southwest.

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Toxic Property

Studies from Colorado State University and Texas A&M University show mountain mahogany to be a toxic plant. Mountain mahogany contains

concentrations of cyanogenic glycosides and may develop hydrocyanic acid (HCN) under certain conditions. The plant is normally, but not always, below

the dangerous level. Effects such as bruising, wilting, withering, or drying of leaves appear to add to the glucoside-enzyme reaction. Wilted leaves due to

cutting the plant appear to be the most dangerous.

All domestic animals are susceptible to HCN poisoning and cattle are the most susceptible. The cyanide blocks the action of the cellular enzyme

cytochrome oxidase and thus prevents hemoglobin from releasing oxygen to the tissues. Death results rapidly from anoxia.

Livestock symptoms:

Hydrocyanic acid (HCN) is one of the most rapid acting poisons. Signs of illness may start within 5 minutes of the time the animal starts eating the plant.

Death may occur within 15 minutes, or the animal may live for several hours. Symptoms in general order of occurrence are as follows:

· Salivation and labored breath

· Muscle tremors

· Incoordination

· Bloating

· Sustained contraction of voluntary muscles

· Bright red venous blood

· Convulsions

· Death due to respiratory failure

Fortunately, even when plants contain considerable quantities of potential HCN, anything that prevents its development in the stomach lessens or entirely

removes the danger of poisoning. Certain feeds such as alfalfa and linseed cake hold back the production of HCN and may prevent poisoning. If symptoms

are typical of HCN poisoning, treatment with sodium thiosulphate will be effective.

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Varieties of Mountain Mahogany

Birch Mountain Mahogany

This plant’s leaves are alternate and persistent; it is commonly at the end of spur shoots. It is about ý to 2 inches long, it is also obviate. The leaves are

dark green or yellow green above the leaf and are lighter in color on the bottom. Its generally smooth margins are jagged about the midpoint and below.

The flower is small, not easily seen, trumpet-shaped, and is also smooth. The birch evergreen shrub may reach 15 feet tall or grow to be 40 feet.

Island Mountain Mahogany

The way to distinguish this plant is, in the shade of this plant are red stipules, which are caduous, abscising soon after the leaf has fully expanded.

Smooth Mountain Mahogany

The name is given to this plant because of its smooth, almost hairless leaves. It is a large shrub or small tree. The flowers are white to yellowish, singly

or in clusters of 3.The fruits are brown, slender, leathery, with a whitish plume like tail at the tip. It may grow up to 20 feet and the width may also be 20

feet. Smooth mahogany blooms in the spring. It may grow on limestone soils.

Silver Mountain Mahogany

The fruit on this plant has white tails. It may look like a threaded needle or a narrow, delicate feather. Fruits are brown, slender, leathery, with a whitish

plume like tail at the tip. The evergreen leaves are about 1 inch long and are a dark green color on the top and are covered with dense white wool on the

underside. The heartwood is a dark brown to red color. It is a shrub. The flower is white to yellowish, singly or in clusters of 3. Its height may grow up to

15 feet and has a width of 15 feet.

Hairy Mountain Mahogany

It is easily identified by it small, narrow leaves and tiny flowers. It is a large shrub and a small tree. The flowers are white to yellowish, and may grow

singly or clustered in 3. Fruits are brown, slender, leathery, with a whitish plume like tail at the tip. It is an evergreen and its height may be 15 feet and

its width is also 15 feet.

Curl-leaved Mountain Mahogany

It is a shrub or small tree which grows from 3-15 feet tall. The trunk and branches are often crooked. The curled leaves and silky curled tails on the fruit

are distinctive. The curled tails on the seeds may straighten out when in dry, hot weather, and curl again in moist conditions. The flexing of the seeds

may help drive the seed into the soil. The leaves are from ý to 1 inch long, and 1/3 to 2/3 of an inch wide. It is dark green and leathery, the even edges

curl under, but the leaf underside are not completely covered .The twigs are a reddish color, and the fruit is feathery, silver-colored, tails are 2 to 3 inches

long. The bark is hard and flaky and up to 1 inch thick.

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Palo Duro

Description:

Palo duro is a variety of cercocarpus montanus. Palo duro means “hard wood” and was given this Spanish name because of the extreme toughness of the trunks and branches. Although true mountain mahogany reaches a much greater height, the wood of the palo duro has a bright red color when freshly cut.

Habitat:

Palo duro grows on bleak rocky slopes and hillsides.

Medicinal uses:

The Tewa Indians recorded that young mountain mahogany in powder form and mixed with cold water is a good laxative.

Other Uses and Values:

The Spanish New Mexicans hang the leafy palo duro twigs around their beds to keep away bedbugs, or dry them, and put them in little bags which are inserted under the mattress for the same purpose. The Navajos use it in preparing a red dye for their wool.