The American elm tree is a popular deciduous broadleaf landscape tree with appealing form and fall colors. The upright-spreading posture of American elms, which produces a beautiful urn-shaped, wide crown, is identification. Leathery, dark green leaves, yellowish-green dangling flowers, and seeds enclosed in a papery casing characterize the American elm, which is a spectacular fast-growing tree.
In the autumn, before the leaves fall, American elm trees’ foliage become a brilliant golden yellow. The deadly Dutch Elm disease (DED) is one of the problems associated with American elm trees.
Thankfully, as a shade tree in your yard, there are several hybrid elm tree cultivars that are resistant to DED. The American elm tree can be identified in a landscape using this guide. Elm leaves, bark, flowers, and seeds are all described and photographed in this guide to identifying the local tree. In addition, you’ll learn ways to grow DED-resistant cultivars in your garden landscape and receive helpful advice.
Facts About American Elm Tree (Ulmus americana)
The American elm (Ulmus americana) belongs to the Ulmaceae family of mature deciduous trees. Native to eastern North America, the American elm is widely found across the US and southern Canada. When mature, the hardy tree reaches 80 to 100 feet (24 to 30 meters) tall in USDA zones 2 through 9.
The gracefully spreading, spreading crown of the American elm makes it a good shade tree. Dark green leathery leaves with serrated edges give the elm tree a rough feel. It’s a popular shade and street tree because of its thick foliage, which provides plenty of shade in the understory during hot summers.
The hardiness of American elm trees is well-known. They’re popular trees in Central and North Florida landscapes, and they thrive in warm and humid climates. Trees such as hardy deciduous trees, on the other hand, will thrive in temperatures as low as 0°F (-18°C) in the northwest.
Moreover, the tree thrives in both wet and dry environments. Water elm, white elm, Florida elm, and soft elm are some of the other names for the American elm tree. Another interesting fact about the elm tree is that it has been employed as a landscaping plant for hundreds of years. Because of its vase-like crown, lovely buttery-yellow fall hue, and adaptability, Ulmus americana has ornamental traits in common with many other elm types.
American Elm Tree Leaves
The leaves on the American elm are dark green, ovate leaves that grow in an alternating, simple pattern. Doubly-serrated margins, an oblique base, and a somewhat bent tip characterize the elm leaves. In the fall, the leaves turn golden yellow and fall to the ground. Leaves range in length from 3 to 6 inches (7 to 15 cm).
American Elm Tree Bark
As the elm tree grows older, its bark becomes grayish-brown and develops deep, diamond-shaped furrows. As the tree ages, the intersected plated bark has a flaky appearance. Peeling the bark of an American elm tree to reveal its wafer-like cross-section is one technique to recognize it in the environment.
American Elm Tree Flowers
The blooms of American elm trees come in March or April. Greenish-yellow blooms with crimson undertones make up the tiny, insignificant flowers. Three to 15 blossoms are in each dangling cluster, and the flower clusters dangle down from stalks up to 1″ (2.5 cm) long. When the tree is in bloom, the flowers lack petals and are difficult to locate.
American Elm Tree Seeds
Seeds from the American elm tree are enclosed in papery casings called samaras and are 0.78″ (20 mm) long. The seed of the flat, oval green-winged samaras is often reddish in color. As the flowers fall and are swept away by the wind, clusters of elm seeds emerge.
American Elm Tree Identification
The spreading vase-shaped crown of the American elm tree identifies it in a landscape. The elm has double-toothed margins and an extended apex when viewed up close. Its ovate leaves are identifiable. The rough bark is grayish-brown, and the furrows are deep. The foliage of the American elm changes to golden yellow in the autumn.
American Elm Trees and Dutch Elm Disease
Elm tree on the left has Dutch Elm Disease (DED). The Dutch elm disease has afflicted the landscape, killing and yellowing leaves on American elms. This vascular wilt sickness is caused by a fungus. As a consequence of the fungus obstructing water from reaching the tree’s branches and stems, it wilts severely.
Beetles that feed on infected trees transmit the illness. European bark beetles (Scolytus multistriatus) infest healthy American elms, and the culprit is responsible. The larvae feed on the fungus that they carry and infect the tree beneath the bark. Yellowing leaves, diseased yellow leaves hanging from branches, and discolored brown sap gushing out of twigs are all symptoms of Dutch elm disease.
American elm tree cultivars resistant to Dutch elm disease
‘Valley Forge’ (left) and ‘New Harmony’ (right) are two American elm tree cultivars resistant to Dutch elm disease. In that situation, it’s critical to choose a cultivar that is resistant to DED. Dutch elm disease resistant cultivars of American elms may be found here:
Valley Forge—The DED-resistant tallest American elm, USDA zone 4. It has lovely arching branches and grows to be 70 feet (21 meters) tall with the classic elm vase shape.
Prairie Expedition—This golden yellow autumn foliage cultivar thrives in zones 3 to 9. This elm tree is capable of growing to be 70 feet (21 meters) tall and has very good disease resistance.
Princeton—One of the most popular disease-resistant American elm trees. It has a nice upright shape and a lovely vase shape.
New Harmony—The crown of this American elm cultivar is wide and urn-shaped, with arching branches that are hardy to zone 5.
Where to Plant American Elm Tree
The appealing Y-shaped form, rich foliage, and excellent shadow qualities of American elm trees make them popular in landscapes. You must, however, investigate a suitable area to plant this fast-growing tree because they are medium to large hardwood trees with a broad spread. To thrive and remain disease and insect-free, American elms need full sun. They should receive at least six hours of sunlight every day. American elms are susceptible to foliar diseases if there isn’t enough light and heat, despite the fact that they can tolerate partial shade.
For the best location to plant an American elm, choose a spot where the soil is always wet but drains well. The type of soil, quality, or drainage, on the other hand, aren’t as important. In sandy, loamy, or clay soils, American elm trees are adaptable and thrive.
The protection of an American elm tree from strong winds is an important consideration. Storm damage is a common occurrence with American elms. Their roots are also shallow, which makes them even more vulnerable. As a result, they should be planted at least 20 feet (6 meters) away from buildings and sidewalks.
How to Plant American Elm Tree
Elm trees are hardy and tough, with particularly disease-resistant Dutch elm elms being the most common. They adapt quickly to most growing conditions and need little care once they are established. So, in your yard, you’d like to plant an American elm. In that situation, here is a resource for you. Next, dig a hole twice as broad as the root ball and about the same depth. Next, remove all the burlap from the nursery plant and if necessary, untangle the roots. Next, using the spade to press down on the tree as you place it in the hole, backfill with native soil.
After that, you should give the newly planted elm tree a thorough watering. This aids in the rooting process by eliminating any air pockets. Next, to help retain moisture and prevent weeds from growing through, apply a 2″ to 3″ (5 to 7.5 cm) layer of organic mulch on top.
For the first week or so after planting, give the elm tree daily watering. Afterwards, when there hasn’t been any rain, water it frequently throughout the growing season. You only have to water the American elm tree during drought periods after it has been planted for a few years.
American Elm Tree Propagation (How to Grow an Elm Tree From Seed)
Cuttings or seeds are the two methods for spreading an American elm tree. Elm tree cuttings are usually the most effective way to propagate. Elms, on the other hand, are rather simple to grow from seed.
To propagate an American elm from cuttings: Ensure that the cuttings are about 6 inches (15 cm) long by taking them from new growth stem tips. Summer after blooming is the ideal time to take cuttings. Next, cut just below the node. Remove all but the final few leaves on the top of the plant.
Next, on either side of the cutting, make a 1″ (2.5 cm) long incision at the base. After that, place in a damp rooting medium made up of peat moss and perlite, and dip in the rooting hormone. Place in a warm, sunny spot with a plastic cover. Roots should emerge in four to six weeks if the soil is kept moist.
To grow an American elm from seed: Harvest and dry harvest elm seeds between March and June using a brown paper bag. Next, carefully remove the papery envelope from the seeds. After that, for 24 hours in room temperature water, soak the seeds. After that, remove the seeds and store them in a sealable plastic container half-full with sand for 30 days in the fridge.
The elm seeds are ready to germinate once you stratify them. Plant the seeds in individual pots using a peat moss and sand combination. Place the growing medium in a warm, sunny location and keep it moist. They are ready for planting outside in the garden when the American elm seedlings reach a height of 6 inches (15 cm).
American Elm Tree (Ulmus americana) Care Guide
Let’s look at some of the best ways to care for an elm tree in your yard, starting with the American Elm.
How to Water American Elm Tree
Watering an mature American elm tree is not required. The ornamental tree is drought-tolerant in comparison to other trees. You should, however, provide additional irrigation during dry periods. Watering the ground around the edge of the crown area is the best way to water an American elm tree. Avoid wetting the leaves or watering the trunk or bark to prevent foliar diseases. As a result, watering an American elm with a sprinkler system would be preferable.
American Elm Tree Fertilization
A low-nitrogen, slow-release granular tree fertilizer is the finest fertilizer for an American elm tree. Therefore, pick a NPK-rated 5-10-10 or 6-12-12 tree fertilizer. Next, pour the correct amount of fertilizer for the tree’s roots into the instructions. Only fertilize in the spring and possibly in the summer if necessary.
American Elm Tree Pruning
Only winter or early spring is appropriate for Pruning an American Elm Tree. Since Elm Bark Beetles are inactive right now, you minimize the risk of your prized elm tree becoming infected by not treating it. Moreover, to eliminate dead branches and prevent branches from rubbing together, yearly trimming is required.
To improve the elm tree’s shape and look while increasing air circulation, you should prune the live branches every three years. Begin by removing a few top and middle branches from the tree’s upper and middle sections. You may also prune limbs that stick out and ruin the tree’s appearance.
It’s worth noting that many states have prohibited elm tree trimming during specific months. To avoid attracting elm bark beetles, it is also preferable to clean all removed branches and foliage. You should also avoid burning pruned branches, which may also draw in harmful insects. It’s best to call in professionals to remove a diseased tree if you see signs of Dutch elm disease.
Top tip when pruning elm trees: Otherwise, the tree might perish if you remove more than one-third of the canopy at a time.
Pests Affecting American Elm Tree Growth
American elms are lovely decorative landscape trees, but they are pests that can be problematic. Elm bark beetles, which spread deadly Dutch elm disease, are the most destructive insect. Native elm trees, on the other hand, may be afflicted by other pests.
European elm bark beetle (Scolytus multistriatus) The DED-causing non-native little brown beetle infects elms. The European beetle feeds on healthy elms, unlike the native elm bark beetle (Hylurgopinus rufipes) that only affects dying elms.
Elm leaf beetle (Xanthogaleruca luteola) The elm beetle feeds on the leaves of elm trees and is an invasive yellow or green beetle. Elm trees are difficult to manage or eliminate beetles that affect them.
Fall webworms The caterpillars are hairy white and live in big silky tents that dangle from the ends of branches. The voracious caterpillars, sometimes known as tent caterpillars, do minimal damage to the leaves surrounding their tents. Removing the tents and tossing them into soap water is the most effective way to eliminate the bothersome insects.
Elm sawfly (Cimbex americanus) The eggs of this black wasp are deposited on elm trees. Large white grubs may completely defoliate elm trees if there is a significant invasion.
Woolly elm aphid (Eriosoma Americanum) The leaves of native elm trees get twisted, curled, and distorted when they are fed upon by this sap-sucking, destructive bug. A cluster of woolly aphids can be seen on the opened leaves. Honeydew and black sooty mold may be present as well.
Diseases Affecting American Elm Tree Growth
In landscapes or along streets, American elm trees are lovely trees. Nonetheless, since the 1930s, illness has ravaged virtually all natural American elm trees. Elm disease affects trees even if many disease-resistant cultivars are available.
Dutch elm disease (Ophiostoma ulmi) Elm bark beetles transmit a fungus that causes this disease. Wilting, yellow leaves that fall early, and other symptoms of this illness are common. Brown streaks with distinct patterns develop on the trunk as the illness advances.
Black leaf spot (Stegophora ulmea) Yellow and black spots appear on the leaves of plants that have a foliar fungal disease. The American elm species is the most likely to contract this illness.
Powdery mildew On the surface of deciduous trees, particularly American elms, it appears as a white waxy or powdery coating. This seemingly benign fungal leaf condition is not a problem since it develops late in the season. Increased air circulation, planting trees in full sun, and avoiding watering leaves are some ways to prevent powdery mildew on elms.