Click on a listing below to see information about that species.
Arizona Ash
(Fraxinus velutina)
Arizona Cypress (Cupressus arizonica)
Austrian Pine (Pinus nigra)
Broadmoor Juniper (Juniperus sabina 'Broadmoor')
Carolina Poplar (Populus canadensis 'Eugenii')
Chaste Tree (Vitex agnus-castus)
Chinese Photinia (Photinia serrulata)
Common Juniper (Juniperus communis)
Common Trumpet Vine (Campsis radicans)
Desert Willow (Chilopsis linearis)
Eastern Redbud (Cercis canadensis)
English Ivy (Hedera helix)
Golden Rain Tree (Koelreuteria paniculata)
Green Ash (Fraxinus pennsylvanica)
Heavenly Bamboo (Nandina domestica)
Honey Locust (Gleditsia triacanthos inermis)
India Hawthorn (Rhaphiolepis indica)
Japanese Boxwood (Buxus microphylla japonica)
Kentucky Bluegrass (Poa pratensis)
London Plane Tree (Platanus x acerifolia)
Maidenhair Tree (Ginkgo biloba)
Mugo Pine (Pinus mugo)
New Mexico Olive (Forestiera neomexicana)
Parney Cotoneaster (Cotoneaster lacteus)
Ponderosa Pine (Pinus ponderosa)
Quaking Aspen (Populus tremuloides)
Scots Pine (Pinus sylvestris)
Siberian Elm (Ulmus pumila)
Silk Tree (Albizia julibrissin)
Tea's Weeping Mulberry (Morus alba 'Pendula')
Weeping Willow (Salix babylonica)
The Arizona ash is a moderately fast-growing tree that is tolerant of hot summers, cold winters, and alkaline soil, making it especially useful in Albuquerque. The male tree produces abundant pollen, and the female produces large amounts of seeds, both undesirable characteristics. The leaves are divided into three to five oval leaflets. Arizona ash is susceptible to ash whitefly and banded ash clearwing borer. It is much less likely to be attacked by the ash bark beetle and other pests than is the green ash.
The Arizona cypress is a conifer with scale-like leaves and woody, globe-shaped cones made up of shield-like scales. The tiny leaves are grayish-green with a point at the tip. Arizona cypress has rough bark that flakes off in patches to reveal a reddish-brown inner bark. Arizona cypress is best adapted to hot climates with dry, alkaline soils. It is native to the trans-Pecos region of Texas to southwestern New Mexico and southern Arizona. It is generally used for windbreaks, and is long-lived. It is often attacked by the cypress bark mealybug which causes branch dieback.
The Austrian pine grows fairly quickly to form a broad, densely spreading, crowned tree of about 50 feet. Its regularly-whorled branches support stiff, shiny, dark green needles in bundles of two. This native of western Asia is very well adapted to cold, windy areas that are relatively dry. Although it is susceptible to the pine tip moth, a healthy tree will be damaged much less than would a ponderosa or mugo pine.
Broadmoor juniper is a short, but broadly spreading juniper with bright green foilage. The foilage is soft and creates a distinct mounding effect. Junipers are the most widely used and overused woody ornamentals in the western US. They are usually overplanted and poorly spaced in urban landsacpes and are ruined by improper pruning. Broadmoor juniper is well adapted to dry, poor soils, but suffers in midsummer from spider mites on dry or dusty sites. Spider mite damage seems to be less where a two- to four-inch layer of mulch is maintained, possibly due to more uniform soil moisture and the increased survival of beneficial insects in course, organic mulches.
The carolina poplar is a fast-growing and generally short-lived tree that is native to the higher elevations of North America. It is very cold hardy and also does well in hot summers, but needs regular moisture. As with most members of Populus, it is subject to a host of leaf-defoliating, stem-sucking, gall-forming, and root-invading insects, and to several leaf spot- and canker-causing diseases. Many members of this genus are prone to branch failure. Carolina poplar is also often the cause of concrete and plumbing failures, creates a network of surface-protruding roots, and produces large amounts of airborne pollen and messy seeds. It should not be planted near building entrances or patio spaces where high maintenance is needed.
The chaste tree is usually a multi-trunked, spreading woody plant that is grown into small trees or large shrubs. It is tolerant of a wide variety of soils and performs best in hot climates. The chaste tree has large spikes of blue flowers in summer and fall, and is heavily used by pollinating and beneficial insects. The leaves are divided into five to seven leaflets that are green above and pale underneath. Varieties are available with white to pink flowers.
Chinese photinia is an evergreen tree or shrub used for its colorful foliage. The dark green leaves with serrated edges turn red in the winter. The new growth is bright reddish-pink. Photinia needs regular pruning, but is fairly drought tolerant. It attracts numerous species of beneficial insects during the blooming period.
Common juniper is native to the Rocky Mountains, and is the most widely used woody ornamental in the Southwest. There are well over 100 types of juniper to choose from, of different colors, textures, and sizes. Most homeowner mistakes are made by underestimating the juniper's mature size. Juniper is best adapted to alkaline soils that remain relatively dry. It is most prone to infestations of spider mites during early spring and late summer, and should be regularly sprayed with a strong fan of water..
The trumpet vine is a large woody vine that climbs vigorously in almost all climates. It is supported by aerial rootlets and may profusely sucker. The leaves are compound with up to 11 leaflets and support clusters of up to 12 orange, tubular flowers. Because of its aggressive nature, trumpet vine can damage fences and walls, and should only be used where there is adequate room to spread. Trumpet vine is a close relative of catalpa and desert willow.
Desert willow is native to the desert Southwest, and is best adapted to gravelly washes and streams in low elevations. Once established, it can survive quite well with no supplemental watering. The abundance of long, narrow fruits and excessive self-seeding can be a problem in some areas. The desert willow is a member of the Bignonaceae, which is also represented on campus by the caltalpa and trumpet vine. Desert willow does not respond well to mechanical injury and has fairly brittle wood.
Eastern redbud is a small tree with simple, heart-shaped leaves. The leaves appear after the pea-shaped, rose-colored flowers are produced on stems at least two years old. The redbud is an understory tree and suffers leaf burn in dry, reflected heat. It is adapted to moist sites such as river bottoms and alluvial sites, and is short-lived. Redbud is a favorite in small patios because of its beautiful spring color, small size, and pest-free status.
English ivy is the most widely planted ground cover in the US. Its roots grow deep and thick and are excellent at controlling erosion. Ivy climbs by aggressive, aerial rootlets, and will destroy a building surface. Ivy should not be allowed to begin to climb in trees because of its tenacious strangling ability. Ivy requires regular maintenance when planted near walkways, buildings, and outdoor features. Unmaintained English ivy also increases the presence of rodents. On the good side, it is fairly drought tolerant.
The golden rain tree is a medium-sized tree that displays bright yellow flowers in large, loose clusters. The fruit is produced in papery capsules that hang down like lanterns. The tree withstands poor soils, heat, cold, and winds, and creates an open and attractive canopy. Golden rain trees should never be planted near building entrances since they attract the red shouldered bug, which can become a serious nusiance.
Green ash is a tree native to the eastern half of the US. It is the most widely planted of all native American ashes. It is relatively fast-growing and does best in rich soils with regular water. It is tolerant of hot summers and cold winters. When stressed, green ash is severely attacked by the ash bark beetle, clear-winged bores, whiteflies, and scales. It is so prone to pests that it is not considered a useful landscape tree. Male trees produce prodigious amounts of pollen. Large amounts of seeds become a litter problem.
Nandina domestica is actually closely related to barberry, but is refered to as bamboo because of its cane-like stems and delicate foliage. It grows best in rich soils with regular water and light shade in hot areas. It needs an iron supplement if planted in alkaline soils. There are many varieties of Nandina to choose from, varying in stem and leaf color to plant size and shape.
The honey locust is native to the central U.S. It is fast-growing, with an upright trunk and spreading, arching branches. The trunk is dark grey with stout, flat, fissured ridges in long strips. The trunk may also possess stout spines in points of three. The leaves are bipinnately compound, with leaflets that are shiny green above and dull green underneath. The fruits are long, dark brown, bean-like pods that contain sweet, edible pulp, thus the name "honey locust." The tree can reach up to 70 feet in height, though few in New Mexico obtain such lofty summits. It is tolerant to a wide variety of soils and temperatures, but definitely does best in hot climates with regular moisture. The honey locust is not shade-tolerant, and requires full sun. Several varieties of honey locust are available for different uses in the landscape, but this tree is probably overused as a landscape ornamental. It is also prone to heaving concrete. Few in Albuquerque have become quality specimen trees. This tree is attacked by the honey locust plant bug as it leaves out in the spring, causing the leaflets to crinkle up and curl. It is also susceptible to the false pit scale insect and various wood borers.
India hawthorn is an evergreen shrub with glossy, leathery leaves and low, compact growth. It is best adapted to full sun, but the leaves burn in hot areas with reflected heat. The flowers are produced in mid-winter and range from white to red. India hawthorn is fairly pest-free in Albuquerque. There are many varieties to choose from for a range of flower color and plant size.
Japanese boxwood is widely used in the Southwest for hedges. Boxwood such as those against Johnson Center are often clipped for a formal, structured appearance. If grown in a more open area and not hedged, it develops into a medium-sized, billowing, and weeping shrub. Hedging practices often increase the incidence of diseases and insect pests. Closely monitor this plant in the summer for scale insects and mites. This type of boxwood is well adapted to our summer dry heat and alkaline soils.
Kentucky bluegrass is a cool-season turf grass with a rich, blue-green leaf. It is used on most parts of campus as the dominant turf grass, but is overseeded with grasses that are less water-demanding. Bluegrasses recover quickly from traffic and abuse and are a necessary component of the campus arboretm due to their ability to tolerate so many visitors and uses. Albuquerque lies in a transition zone for both cool- and warm-season grasses. Bluegrass in Albuquerque reaches peak growing acitvity in September and October, and again in March and April. It naturally goes dormant during the hot parts of the summer. The bluegrass at UNM is maintained to be dormant during December, January, and February due to potential ice conditions, and is pushed to green during the hot summer to support campus activities. To lessen the University's water demands, Kentucky bluegrass is overseeded with compatible cool-season grasses such as fine leaf fescue and annual rye grass varieties.
The London plane tree is a hybrid between the eastern US sycamore and the oriental plane tree of Europe. It grows to become a large, stately tree with smooth, cream-colored branches, and bark that sheds in patches to reveal lighter bark beneath. It can reach 90 feet in height, and can spread to over 40 feet in width. It is often used in streetscapes and mall areas because it tolerates a wide variety of conditions. The tree does suffer greatly from the sycamore scale insect if it is drought-stressed or in areas with a high level of reflected heat. The London plane tree has three- to five-lobed leaves that resemble maple leaves, thus the species name acerifolia. The fruit is produced in clusters of balls hanging on stalks. Although the London plane tree can become chlorotic in high alkaline soils, the trees here at Johnson Center exhibit a light green to yellow leaf that is a genetic characteristic.
The ginkgo is a hardy and attractive tree native to China, and is actually closely related to conifers. It is the last surviving member of what was once a large and variable family of trees. Pollen is produced in cones on male trees, and the seeds, produced on female trees as in conifers, are naked, with a thin, juicy pulp that gives the tree a disgusting odor. For this reason, ginkgos should only be selected from nursery stock to ensure planting of a named variety of the male sex. The leaves of the ginkgo are fan-shaped, with two lobes, and are a light, dull green, turning a striking gold in fall. Their shape resembles the leaf shape of the maidenhair fern, which has led to the moniker of "maidenhair tree." Its bark is grey, and is deeply furrowed on older trees, which can reach 60 feet in height. The ginkgo is widely planted as a street tree since it is tolerant of a wide range of environmental conditions, and is essentially insect- and disease-free.
Mugo pine is a small, shrubby tree that has a nice appearance in rock gardens. Most mugo pines, such as those on the southwest corner of Johnson Center, suffer from attack of the pine tip moth.
New Mexico Olive is native to parts of the arid Southwest. It is generally multi-trunked and grows to 10 to 12 feet tall. Plants that have both male and female flowers (not all do) produce dark blue, 1/4" fruit that is an important food for birds. The ripened fruit stains walkways and walls easily, so it is best to plant fruiting trees away from hardscapes. The edges of the 1"- long, smooth green leaves are often curled due to attack of eriophyid mites.
Cotoneaster is well-adapted to dry, low-maintenance areas with poor soils. Unfortunately, it is too frequently planted near walkways and turf borders where the required subsequent pruning destroys its natural, beautiful, arching and weeping shapes. C. lacteus in particular needs ample room to spread as it grows to ten feet and more. When unpruned, it will produce prodigious amounts of long-lasting clusters of red fruits. Although most members of the Rose family are favorites of insects and disease, cotoneaster is fairly free of pests in the Albuquerque area. Many different species and varieties are available for different site requirements.
Ponderosa pine is a fast-growing tree native to western North America. It has long, stout needles in bundles of threes and cones with a distinct, sharp awns. Ponderosa pines can grow to 200 feet and are tolerant of a variety of soils, but need good drainage. Due to its intense maintenance requirements for insect pests, ponderosa pine is usually not the best choice of conifer for Albuquerque landscapes.
The aspen is native throughout the northern and western mountains of the U.S. Its trunks and branches have smooth, pale green bark and light green, round leaves that tremble on their flat petioles at the slightest breeze. The leaves turn bright gold in the fall. The aspen is a pioneer species after fires -- it is fast-growing, short-lived, and is eventually replaced by conifers. It is important for wildlife, as the twigs and buds are browsed by deer, elk, sheep, grouse, and quail, and the bark is food for beavers, rabbits, and other mammals. The aspen is not recommended for planting in Albuquerque, as it requires regularly moist soils, and suffers from heat stress and disease.
The Scots pine is native to Europe and Asia, and because of its large and beautiful shape, has been widely planted and naturalized across Canada and the U.S., making it the most widely distributed pine in the world. Its bark becomes reddish with age, and flakes off in thin, papery patches. Its blue-green needles are in bundles of two, and are flattened and twisted. This tree is hardy in Albuquerque, but performs less well in low desert areas. It may reach 90 feet in height.
The Siberian elm requires more maintenance and causes more infrastructure problems than any other landscape tree. Its chief maintenance requirements include regular treatment of a variety of insect and disease pests and careful pruning to prevent failure of large branches. It is aggressive, is prone to surface rooting, and produces large amounts of pollen and seeds. Siberian elm is the scourge of the grounds manager. On the plus side, it will grow well in almost any site condition. Although Siberian elms are no longer planted as landscape trees, several specimens exist on campus that are over 40 years old, and they receive the utmost care.
The silk tree is native to Asia and Africa, and has been widely planted in the warm climates of the US. It is a small- to medium-sized tree outside its native range, and develops a broad, flat top with age. The leaves are bipinnately compound with up to 30 pairs of small, narrow leaflets. The flowers are grouped in showy pink clusters with numerous stamens. Silk tree leaves, flowers, and fruits can produce abundant litter, but the tree is worth the effort in the right location. The silk tree is also very susceptible to verticillium wilt from root injury, and often is infected with cytospora fungal disease if injured. The variety 'Rosea' has darker flowers and is more hardy for our area.
Teas weeping mulberry is a variety of white mulberry that is medium-sized with strongly weeping branches. Most varieties are sold as fruitless due to the abundance of dark red fruits that stain walkways and patios. Like other mulberries, it is best suited to dry, alkaline soils and desert heat, but is a heavy producer of airborne pollen. Mulberries should not be planted near building entrances or in patios due to their maintenance requirements.
Weeping willow is a fast-growing and short-lived tree native to China where it thrives in river bottoms and flood plains. It is not very successful on upland urban landscapes, although it is prized for its long, sweeping branches. Willow is attacked by a variety of insects and diseases, and produces invasive roots. It is not known for developing a strong branching system, and thus is prone to branch failure and storm damage. Except for low-lying and frequently flooded areas, willow is a poor choice for Albuquerque landscapes.