Common Conifers in New Mexico Landscapes
Total Page:16
File Type:pdf, Size:1020Kb
Ornamental Horticulture Common Conifers in New Mexico Landscapes Bob Cain, Extension Forest Entomologist One-Seed Juniper (Juniperus monosperma) Description: One-seed juniper grows 20-30 feet high and is multistemmed. Its leaves are scalelike with finely toothed margins. One-seed cones are 1/4-1/2 inch long berrylike structures with a reddish brown to bluish hue. The cones or “berries” mature in one year and occur only on female trees. Male trees produce Alligator Juniper (Juniperus deppeana) pollen and appear brown in the late winter and spring compared to female trees. Description: The alligator juniper can grow up to 65 feet tall, and may grow to 5 feet in diameter. It resembles the one-seed juniper with its 1/4-1/2 inch long, berrylike structures and typical juniper foliage. Its most distinguishing feature is its bark, which is divided into squares that resemble alligator skin. Other Characteristics: • Ranges throughout the semiarid regions of the southern two-thirds of New Mexico, southeastern and central Arizona, and south into Mexico. Other Characteristics: • An American Forestry Association Champion • Scattered distribution through the southern recently burned in Tonto National Forest, Arizona. Rockies (mostly Arizona and New Mexico) It was 29 feet 7 inches in circumference, 57 feet • Usually a bushy appearance tall, and had a 57-foot crown. • Likes semiarid, rocky slopes • If cut down, this juniper can sprout from the stump. Uses: Uses: • Birds use the berries of the one-seed juniper as a • Alligator juniper is valuable to wildlife, but has source of winter food, while wildlife browse its only localized commercial value. Dense alligator foliage. The trees have little commercial value juniper populations are thinned to improve outside their occasional use as firewood, potpourri, wildlife habitats. and fence posts. Pests: Pests: • The alligator juniper pests are the same as the one- • Spider mites seed juniper. • “Cedar”’ bark beetles • Western cedar borer • Tiger moth (occasionally) • Gymnosporangium rusts • True mistletoes New Mexico Extension Master Gardener Manual—First Edition IV.H.1 New Mexico Extension Master Gardener Manual Pests: Insects and diseases are usually not serious problems on well-cared-for trees. Pests include: • Spider mites • Bark beetles • Western cedar borer • Spittlebugs • Juniper twig pruner • True mistletoe • Gymnosporangium rusts. Rocky Mountain Juniper (Juniperus scopulorum) Description: The Rocky Mountain juniper is a small, evergreen tree that grows up to 35 feet in height. A native of western North America, it occurs in mixed or pure stands of open woodland in New Mexico and Arizona at elevations of 5,000-8,000 feet. It also often occurs on dry, rocky ridges. It does well in cultivation, adapting to a wide range of soils and moisture conditions. It is winter-hardy, slow- growing, and very long-lived. The fruits are blue with a whitish bloom-fleshy berries Eastern Red Cedar (Juniperus virginiana) (cones) about 1/4 inch in diameter. They ripen in the second season. The flowers are small and conelike. Description: The eastern red cedar is a medium They are borne separately on male and female plants. evergreen tree, commonly 10-40 feet, having a The leaves are opposite, scalelike and pale blue-green pyramidal shape that becomes rounded with age. to dark green. On new shoots, the leaves are awl- Like most junipers, it is very slow-growing and shaped, sharp-pointed and spreading. Stems often moderately long-lived. The fruits are pale blue with a divide near the ground with thick and ascending whitish bloom-fleshy berries (cones) about 1/4 inch branches. The bark is red to gray-brown, furrowed, across. They ripen in the second season. The flowers thin and shredded. The roots are wide-spreading. are small and conelike. They are borne separately on male and female plants. The pale to dark green leaves A closely related species is the Utah juniper—a smaller are opposite and scalelike, covering older twigs plant with bluish, one-seeded fruit. A common and closely in alternating pairs. On new shoots, the typical tree of Great Basin ranges, it is little known leaves are awl-shaped, sharp-pointed and spreading. in cultivation. New stems are short, often dividing near ground with thick and ascending branches. The bark is red Other Characteristics: to gray-brown, furrowed, thin and shredded. The • It is tolerant of droughty and moist sites. However, roots are wide-spreading. The eastern red cedar has the moist sites must be well-drained. many intergrading varieties, differing in color and growth form. Uses: • The Rocky Mountain juniper can be used as a Other Characteristics: windbreak in the outer rows of multirow plantings, • Native to eastern North America, but cultivated in where it will not be overtopped by taller trees. It New Mexico. also can be used in single-row windbreaks, when a • Planted most successfully at elevations below dense, medium-height barrier is desired. 7,000 feet. • This species of juniper provides food and cover for • Is very winter-hardy and tolerant of droughty and numerous birds and mammals; winter food and salty soils. protection is particularly important for pheasant, mule deer, and whitetail deer. Uses: • The Rocky Mountain juniper’s yearlong coloration • For cultivation, the eastern red cedar requires dry and attractiveness to wildlife makes it useful for soils and full sunlight. This species offers great recreational plantings. hardiness for some planting sites. IV.H.2 Ornamental Horticulture • For use as a windbreak, plant this species in the • This cypress makes an excellent nesting habitat for outer rows of multirow plantings, where it will not small birds and cover for small game. be overtopped by taller trees. It can be used in Pests: single-row windbreaks when a dense, medium- • Bark beetles height barrier is desired. • Flat headed borers, the western cedar borer • The eastern red cedar provides food and cover for • Spider mites numerous birds and mammals, especially in winter. • Twig pruners • It is suitable for screen plantings. • Cypress scale Pests: • Same as Rocky Mountain juniper. Giant Sequoia (Sequoiadendron giganteum) Description: The species includes the largest living beings. They potentially can grow to 150 feet when cultivated and to 250 feet in the wild. The crown is Arizona Cypress (Cupressus arizonica) conic and becomes broader with old age or when the top is lost in lightning strikes. The bark is thick red Description: The Arizona cypress is an evergreen tree brown or dark brown. It often is fluted, fissured, and growing to a height of 35-50 feet with a spread of 10- strongly ridged, thick, and moderately soft. The 15 feet at the base. The foliage is scalelike and blue- shoots are green, becoming red-brown during the green in color. The bark is cherry red to gray. The fruit second season. The foliage occurs in rather wiry sprays is a globular cone about 1-1 1/4 inches in diameter. set all around the shoot. The cones are green ripening to brown or green in the second year. After the second Other Characteristics: year, they are woody and ovoid, persisting on the tree. • Best planted at elevations of 6,500 feet or lower. • Possesses drought tolerance as well as an ability to Other Characteristics: withstand considerable heat. • Native to the western slopes of the Sierra Nevada in California. The trees are most common in about Uses: six dozen groves in the southern part of its range. • For cultivation, the Arizona cypress does best on • The giant sequoia is very tolerant of cold and well-drained soils. It also does well in low precipita- dry sites. It has been recorded to live as long as tion areas with irrigation. Container-grown stock 3,500 years. is recommended. Bare rootstock also may be used. • Some of the nicest examples in New Mexico are in However, more care in planting and early mainte- Santa Fe and Los Alamos. nance is required, and poorer survival rates can be expected. Trees grown from seed vary considerably Pests: in form, density, and foliage color. Improved • Giant sequoia is relatively free of serious insect and varieties have been introduced, which are propagated disease problems in landscape settings. Due to size, vegetatively, assuring uniformity of appearance. older specimens are prone to damage from light- • The Arizona cypress can serve as a windward row ning. Lack of water can stunt the tree and cause in a multirow windbreak and as a dense single- browned foliage. row windbreak. It will make an attractive hedgerow, if pruned annually, but will not sprout from older branches. IV.H.3 New Mexico Extension Master Gardener Manual Other Characteristics: • Deodar cedar is native to the drier western Himalayas from west Nepal to eastern Afghanistan. It does well in New Mexico at elevations of 6,000 feet or below. Because of its range of habitats in the Himalayas, it shows variation in ability to with- stand winter cold. The plants from the west of the range in Pakita province, Afghanistan generally are more hardy. The ‘Cashmere’ variety appears to be hardy in Santa Fe (7,000 feet). The ‘Shalamar’ variety reportedly is also hardy in Santa Fe, but has been less available. True Cedars, Atlas Cedar (Cedrus Atlantica) • Deodar is tolerant of dry sites and is very hardy, although the needles may be damaged at the tips Description: The Atlas cedar is native to the Atlas during some winters. Mountains of Morocco and Algeria and can grow to a height of 60 feet in cultivation. In the wild, the trees Pests: vary in the development of the wax associated with • No significant pests have been noted. stomatal bands, resulting in very blue trees and less attractive gray-green ones. The trees generally are grown in the warmer parts of New Mexico but also have performed well up to 7,000 feet in elevation.