Showy Mountain Ash in fall
Showy Mountain Ash in fall
(Photo courtesy of NetPS Plant Finder)
Showy Mountain Ash flowers
Showy Mountain Ash flowers
(Photo courtesy of NetPS Plant Finder)
Showy Mountain Ash fruit
Showy Mountain Ash fruit
(Photo courtesy of NetPS Plant Finder)
Height: 25 feet
Spread: 15 feet
Hardiness Zone: 2a
A hardy accent tree for small landscapes, featuring showy clusters of white flowers in spring followed by bright scarlet berries lasting into winter; attractive compound leaves turn red and orange in fall; needs well drained soil, resistant to fireblight
Showy Mountain Ash features showy clusters of white flowers held atop the branches in mid spring. The red fruits are held in abundance in spectacular clusters from early to late fall. It has dark green foliage throughout the season. The oval compound leaves turn an outstanding red in the fall. The smooth gray bark adds an interesting dimension to the landscape.
Showy Mountain Ash is a dense multi-stemmed deciduous tree with a shapely oval form. Its relatively fine texture sets it apart from other landscape plants with less refined foliage.
This tree will require occasional maintenance and upkeep, and is best pruned in late winter once the threat of extreme cold has passed. It is a good choice for attracting birds to your yard. It has no significant negative characteristics.
Showy Mountain Ash is recommended for the following landscape applications;
Planting & Growing
Showy Mountain Ash will grow to be about 25 feet tall at maturity, with a spread of 15 feet. It has a low canopy with a typical clearance of 3 feet from the ground, and is suitable for planting under power lines. It grows at a medium rate, and under ideal conditions can be expected to live for 40 years or more.
This tree should only be grown in full sunlight. It is very adaptable to both dry and moist locations, and should do just fine under average home landscape conditions. It is not particular as to soil type or pH. It is highly tolerant of urban pollution and will even thrive in inner city environments. This species is native to parts of North America.
Gertens Sizes and Prices
- Showy Mountain Ash Care – Can You Grow A Showy Mountain Ash Tree
- Showy Mountain Ash Information
- Can You Grow a Showy Mountain Ash?
- Showy Mountain Ash Care
- Showy Mountain Ash
- European mountain ash
- Size & form
- Tree & Plant Care
- Disease, pests, and problems
- Native geographic location and habitat
- Attracts birds & Butterflies
- Bark color and texture
- Leaf or needle arrangement, size, shape, and texture
- Flower arrangement, shape, and size
- Fruit, cone, nut, and seed descriptions
- Cultivars and their differences
- Mountain Ash Tree
- Appearance of the Tree
- Rowan-Mountain Ash Tree Types
- The Many Looks of the Rowan Tree
- Where the Mountain Ash Grows
- Popular Uses
- Interesting Facts
- Rowan/Mountain Ash Diseases
- Mountain Ash Care
- Rowan (Mountain Ash) Trees
Showy Mountain Ash Care – Can You Grow A Showy Mountain Ash Tree
Showy mountain ash trees (Sorbus decora), also known as northern mountain ash, are small American natives and, as their name suggests, very ornamental. If you read up on showy mountain ash information, you’ll find that the trees flower profusely, produce attractive berries and offer a stunning fall display. Growing showy mountain ash isn’t difficult if you live in a cooler climate. Read on for tips on showy mountain ash care.
Showy Mountain Ash Information
While ash trees grow very tall in cool and moderate hardiness zones, mountain ash are much smaller. They are not in the same genus as ash trees and are native to the northern states. Showy mountain ash trees grow to about 30 feet (9 m.) tall and about half to three-quarters that wide. Their branches grow in an ascending direction and start from very low on the trunk.
If you start growing showy mountain ash, you will love the blossoms and berries. The showy white flowers appear in late spring or early summer. They are fragrant and attract pollinators. These are followed by heavy clusters of bright berries in autumn that are appreciated by many types of wild birds. The berries from showy mountain ash trees are also eaten by small and large mammals, including humans.
Can You Grow a Showy Mountain Ash?
So can you grow a showy mountain ash? It depends first on where you live. These are trees that require a cool climate and only thrive in U.S. Department of Agriculture plant hardiness zones 2 through 5. If you are ready to start growing showy mountain ash, look for a full-sun site for planting. These trees do not tolerate shade.
Planting the trees in an appropriate site is a big part of showy mountain ash care. These natives do not tolerate pollution, drought, heated areas, compacted soil, salt or flooding. If you select an area free of these issues, your showy mountain ash tree will have a good chance of thriving.
Showy Mountain Ash Care
Once you have planted these trees in a good location, care is not difficult. Provide these trees regular irrigation, especially during the year or so after transplant.
Never fertilize showy mountain ash trees. Fertilizer is generally not recommended for any native trees.
You may want to keep an eye out for pests. Although mountain ash aren’t attacked by the emerald ash borer, they can get fire blight disease. Look for help if the branch tips suddenly turn black and droop.
Flat or rounded cluster to 6 inches across of short-stalked flowers at the tips of 1-year-old branches, blooming when leaves are mature. Flowers are ¼ to ½ inch across, white with 5 rounded petals. In the center are 2 to 4 short, yellowish styles surrounded by about 20 white, ascending to spreading stamens. The calyx around the base of the flower has 5 short, triangular lobes, is usually hairless though may have a few glands. Flower stalks are hairless or with sparse, long, soft hairs.
Leaves and bark:
Leaves are alternate, 6 to 10 inches long, compound with 11 to 17 leaflets. Leaflets are lance-oblong, 1½ to 2½ inches long, ½ to 1 inch wide (2.5 to 3.3 times as long as wide), often abruptly tapered to a pointed tip, asymmetrical and rounded to wedge-shaped at the base, and stalkless. Edges are sharply toothed, sometimes only on the tip half, and the tooth at the very tip is typically slender and elongated. Surfaces are initially downy hairy but quickly become smooth, though a few hairs may persist along the midvein and vein axils on the underside. The compound leaf stalk is hairless and often reddish. Leaves turn red in fall.
Buds are shiny, sticky, dark purple, and with short, yellowish to light brown hairs at the tip and/or around the edge of scales. New twigs are green to brown, hairless to hairy, becoming reddish brown and smooth with scattered, pale lenticels (pores) the second year.
Older bark is gray to gray-brown, smooth but developing plates and scaly patches that eventually peel off. Trunks are single or multiple from the base and can reach up to 12 inches diameter at breast height (dbh).
Showy Mountain-ash reaches the western edge of its US range in Minnesota and typically grows as a small tree on bluffs, in upland and swamp forests, and is a common sight on the rocky north shore of Lake Superior. It is easily mistaken for the related, and less common, American Mountain-ash (Sorbus americana), which has leaflets that are 3.3 times or more as long as wide (divide length by width to determine), typically hairless all over, and has somewhat smaller flowers and fruits (both to 1/3 inch). European Mountain-ash (Sorbus aucuparia), a landscape tree than occasionally escapes cultivation, has smaller leaflets up to 1½ inch long, and is hairy on leaf stalks, sepals, leaflets, has more densely hairy buds, and the terminal tooth on leaflets is much the same as the lateral teeth, not slender and elongated. Note that Mountain-ash is unrelated to Ash trees (Fraxinus species) and not at risk from emerald ash borer.
Showy Mountain Ash
Showy mountain ash (Sorbus decora) also known as northern mountain ash is a native of Iowa. It is a large shrub or small tree similar to the American mountain ash, but different because the leaflets are narrow, oblong-oval, only 2 to 3 times as long as broad with a pointed tip, and paler (whiter) beneath.
Showy Mountain Ash Tree – Photo by Bill Cook, Michigan State University, Bugwood.org
Habitat: Found only in extreme northeast Iowa, requires well drained fertile soil.
Hardiness: Zones 3 through 9
Growth Rate: Moderate to Fast
Mature Shape: Slightly pyramidal, upright with a rounded crown
Height: 50- 80 feet
Width: 50-70 feet
Site Requirements: Native to Iowa, ash trees grow best in full sun and moist, well-drained soils. Ash trees are tolerant of a wide range of soil conditions.
Leaves: Opposite-branching and pinnately compound
Flowering Dates: May – July
Seed Dispersal Dates: August – June
Seed Bearing Frequency: Yearly
Seed Stratification: Prechill for 2 months at 34°F to 40°F
The flowers are larger than American mountain ash; 3/8 inch across, and the cluster is more diffuse. The fruits are also larger at 3/8 inch across.
Its range is from southern Greenland, Labrador, and Newfoundland westward to northern Ontario and Minnesota; and southward to Maine, New York, Ohio, northern Indiana, and extreme northeast Iowa. It can be found naturally occurring in woodlands and on rocky shores and slopes preferring well drained rich soil.
Showy Mountain Ash Flowers – Photo by Bill Cook, Michigan State University, Bugwood.org
Diseases that Can Affect Showy Mountain Ash
- Ash Rust
- Ash Decline
- Verticillium Wilt
Insects that Can Affect Showy Mountain Ash
- Emerald Ash Borer
- Ash Spider Mite
- Pear Sawfly or Pearslug
- Ash Plant Bug
- Ash Sawflies
- Ash/Lilac Borer
- Leafcutter Bees
- Oystershell Scale
Showy Mountain Ash Leaves – Photo by Bill Cook, Michigan State University, Bugwood.org
Showy Mountain Ash Fruit – Photo by Bill Cook, Michigan State University, Bugwood.org
European mountain ash
Size & form
A small tree, 20 to 40 feet tall and 15 to 25 feet wide.
A short-lived tree, best grown in cool climates.
Tree & Plant Care
Plant in a cool moist location. Does best in full sun but will tolerate some shade.
This tree prefers well-drained, slightly acidic soils.
May be difficult to find in nursery trade,
Disease, pests, and problems
Prone to many insect and disease problems
Borers and cankers are serious problems on stressed trees.
Native geographic location and habitat
Native to northern Europe and Asia
Attracts birds & Butterflies
Flowers attract butterflies and fruit is a favorite of many bird species.
Bark color and texture
Smooth gray bark with white streaks from lenticels. Older bark is slightly rough.
Leaf or needle arrangement, size, shape, and texture
Alternate, pinnately compound (9 to 15 leaflets), slightly serrated leaf margins.
Dull dark green above, paler beneath. Yellow to reddish orange fall color.
Flower arrangement, shape, and size
White, 5-petaled flowers in flat-topped clusters in May. Flowers have a slightly unpleasant odor.
Fruit, cone, nut, and seed descriptions
Clusters of small, red berry-like fruit (pomes).
The common name Rowan refers to the old Scandinavian word meaning red.
Cultivars and their differences
Common Name: Mountain Ash
Species: E. regnans
Size and Growth Rate: Mountain ash grows relatively quickly, with an average annual growth rate of 3 feet (1 meter). They are the tallest of the eucalypts, capable of reaching heights of up to 490 feet (150 meters) but generally grow to about 330 feet (100 meters). It’s the world’s tallest flowering plant.
Life Span: Mountain ash has an average lifespan of 400 years.
Reproduction: The primary form of reproduction occurs through dispersal of seeds. This process is often initiated during severe fires when intense heat releases seeds from their hard casings, called gumnuts. The seeds germinate on the forest floor, receiving a boost of nutrients from the ashes left behind from the fires, and flourishing in the sunlight which reaches the ground through now-bare tree branches. Mountain ash trees can also regenerate through shoots sprouting from dormant buds protected beneath the fire-insulated bark., or which are stimulated when trees suffer significant loss of top growth—though this form of regeneration happens far less frequently.
Appearance: The base of the tree is quite rough but, as the tree grows, this rough bark sheds large ribbons, leaving the highest part of the tree with a smoother exterior. The lowest branches are nearly 100 feet from its base. The mountain ash leaf varies in shape; clusters of white flowers blossom during Australia’s summer and autumn months, January to March.
Habitat: The mountain ash grows in deep soil in the cool, mostly mountainous areas of Victoria and Tasmania on the Australian continent. These regions are located at an approximate altitude of 3,300 feet (1,000 meters) with an average annual rainfall of 47 inches (1200 millimeters).
Conservation Status: The species is not considered to be at risk of extinction.
- Mountain ash is a common name given to other unrelated species of trees, such as the Fraxinus texensis in Texas, the Sorbus in North America, and the Sorbus aucuparia, found mostly in Ireland and Britain.
- In addition to mountain ash, the species has also been referred to as Victorian ash, swamp gum, Tasmanian oak and stringy gum.
- The Australian mountain ash is the tallest flowering plant, and the tallest of the eucalypts.
- Only California coastal redwoods are taller, though their heights are comparable.
- The species is an evergreen, maintaining its leaves year-round.
- Mountain ash is part of a diverse group of plants known as Angiosperms, or flowering plants, classified for their seed, flower, and fruit production.
- Its leaves produce volatile, highly combustible oils.
- Mountain ash produces excellent hardwood timber prized by the lumber industry for building and paper products, and also provides essential habitat for a wide variety of birds and mammals, including the endangered Leadbeater’s possum.
Mountain Ash Tree
The mountain ash is actually not an ash but a member of the rose family. Sorbus aucuparia is a European native and the most widely planted of a large group of similar shrubs and trees. The native mountain ashes are just as beautiful, but most species tend to be shrubby in nature. The European mountain ash has a more distinctly treelike form.
Description of mountain ash tree: This small to medium tree (up to 50 feet tall) has light grayish bark and an oval, open head at maturity. It produces clusters of white flowers in spring followed by bright, long-lasting, orange-red berries in fall that attract birds. The deciduous leaves are toothed and pinnately compound. They are dark, dull green in summer and yellow to reddish in fall.
Growing mountain ash tree: Grow in full sun in rich, well-drained, acid soils. It is short-lived under alkaline conditions. The tree transplants well. Mountain ashes are highly susceptible to borers and fireblight, among other pests. They are best grown in the northern part of their range where cool summers are not conducive to these problems.
Uses for mountain ash tree: Mountain ash is a good small tree for home landscapes and is especially appreciated for its long-lasting berries.
Related species of mountain ash tree: The white beam mountain ash (Sorbus aria) has the same form and berries as the more common mountain ashes, but with totally different leaves. They are not compound and the undersides are covered with attractive white felt.
Related varieties of mountain ash tree: There are many selections of this tree with variously colored berries, from red to pink to yellow, weeping or upright forms, or doubly compound leaves.
Scientific name of mountain ash tree: Sorbus aucuparia
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Mountain Ash or Rowan trees are a popular ornamental species derived from the genus Pyrus. The trees are referred to by both names, though the Mountain Ash moniker is used primarily in North America, while Rowan is the preferred name in Europe. Regardless of what you call the garden tree, its appearance remains the same. The Mountain Ash is an attractive specimen which bears pretty flowers and bright decorative fruit.
Appearance of the Tree
The Mountain Ash is not part of the Ash tree family at all. It actually belongs to the same species as the rose bush, the Rosaceae. Most Mountain Ashes are shaped like shrubs, though some have a more traditional tree-like form and can grow to 50 feet tall.
The tree features several other noteworthy characteristics, including:
- Leaves: Compound with up to 15 tiny leaflets. The pinnate are relatively long, measuring up to nine inches on some types. The leaves are dark green in the spring and summer but change to a spectacular mix of yellow, red and orange in the fall. Typically the leaves are paler on their underside.
- Bark: Light grayish bark with raised dots. The bark turns brown-gray as the tree matures.
- Flowers: Large clusters of small white flowers blossom in the spring. Each bloom yields five petals.
- Fruit: Bright orange-red berries form a cluster in late summer and can be harvested in the fall. Depending on the type of tree, the berries can range in color, including white, yellow, pink, peach, bright orange or red. The berries are edible, but are extremely acidic and do not have a pleasant taste.
The small tree is a great addition to home landscapes and can survive more than 100 years if well cared for.
Rowan-Mountain Ash Tree Types
Mountain Ash trees are not related to true Ash trees which belong to the genus Fraxinus. Rather, the small deciduous specimens feature two main species:
- European Mountain Ash: This type of Mountain Ash bears more resemblance to a traditional tree. It is not as shrubby as the North American version, though it still bears the iconic bright fruit and delicate creamy white flowers.
- North American Mountain Ash: This version of the Mountain Ash grows to a more manageable height for the average homeowner looking to add the tree as a landscaping specimen. The North American Mountain Ash does not tolerate warm climates. The tree is known for its fiery red foliage in the fall and makes for a stunning addition to a suburban backyard.
- White Beam Mountain Ash: This Mountain Ash tree is commonly found in cooler climates. It differs from its cousins, the European and North American Mountain Ash trees, in that its leaves are not compound and the undersides are covered with white felt-like hairs.
The Many Looks of the Rowan Tree
Where the Mountain Ash Grows
Rowan/Mountain Ash trees grow naturally in:
- North Africa
In North America, the tree prefers colder climates, moist soil, and full sun. It is especially prevalent in the Pacific Northwest where it is considered a top pick among landscapers who can cultivate the tree with much success given the region’s temperate conditions.
In addition to adding a splash of color to green spaces, the Mountain Ash tree serves a number of other practical purposes such as:
- Food: Eating the Mountain Ash’s berries raw is an unpleasant experience. However, when cooked, they are delicious in jams, pies, and wine.
- Drink: In Europe, the berries of the Rowan tree were, at one time, used to create a distilled spirit most similar to a beer.
- Medicine: Mountain Ash berries contain high levels of Vitamin C. Some cultures used to squeeze the juice from the berries, and drink it to prevent scurvy. Today, the berries are placed in tea and consumed to treat urinary tract infections and diarrhea. In some cases, the fruit juices are extracted and administered intravenously to treat glaucoma. Centuries ago, the bark from the tree was used as a blood cleanser.
- Wood: Timber from the Mountain Ash is quite durable and is used to make tool handles, walking sticks, furniture, planks, and beams.
The Mountain Ash’s large rounded canopy is also a popular home for birds that enjoy snacking on the tree’s berries which grow in chunky clusters.
The Mountain Ash played a pivotal role in European mythology. The tree was thought to have magical powers, including the ability to protect houses and ships from lightning strikes.
In some Celtic cultures, the Mountain Ash is referred to as the “Traveler’s Tree” because it was thought to protect people from getting lost.
Other interesting facts associated with the tree include:
- In Ancient England, legend had it that Satan hung his mother from the branch of a Mountain Ash tree.
- Centuries ago magic wands were fashioned from Mountain Ash twigs.
- In parts of Europe, wood from the Mountain Ash tree would be erected near graves to keep the dead from haunting.
- In Newfoundland, residents would predict the weather based on how many berries were harvested in a season. A large crop would mean a hard winter was approaching.
- In Finland, some believed that if the Mountain Ash experienced an exceptional bloom, the rye harvest would be plentiful.
Meanwhile, in Sweden, it was thought that if the Mountain Ash lost color prematurely, the fall and winter would bring illness.
Rowan/Mountain Ash Diseases
Healthy Mountain Ash trees are gorgeous specimens that can help brighten up even the most unattractive yards. However, the species is not immune to diseases that can rob it of its beauty and charm.
Among the most common infections that afflict the Mountain Ash tree include:
- Cytospora Canker: This fungal disease targets the tree’s trunk and branches by peppering it with brown, irregular shaped cankers. The ugly pimple-like masses can ooze and spread throughout the Mountain Ash. In a severe case, the disease can kill the tree.
- Fire Blight: This infection kills the tree’s flowers and leaves. Symptoms include black leaves, brown flower clusters, and spores that ooze slime and infect the tree’s branches.
- Leaf Spot: This shows as irregular, brown spots on leaves. If left untreated, tiny, black spores will form as well. Advance cases also cause leaves to drop prematurely.
Mountain Ash is also susceptible to sawflies which can defoliate the tree within a few days.
Mountain Ash Care
At first glance, Mountain Ash trees look like they’re high maintenance saplings, but even if you have just the slightest green thumb you shouldn’t have a problem getting the tree to prosper on your property. These tips will help you get started:
- Mountain Ash trees prefer full sun. Avoid planting the tree in the shade of a large building or near trees that tower over it. If the tree is robbed of sunlight, its flower and fruit production will be reduced.
- The tree grows better in slightly moist, acidic soil. Do not over water the Mountain Ash.
- Most Mountain Ash types do not need to be fertilized, though if your soil lacks nutrients you could add some fertilizer to the base of a young tree.
- Pruning is essential with Mountain Ash trees as it needs to be trained to maintain a single trunk. If regular maintenance is not done, the tree will become multi-stemmed over time.
- Mountain Ash doesn’t fare well when exposed to pollution, road salt, and animals that like to gnaw on tree bark. As such, it’s not a good idea to plant the tree along a busy street or in an urban environment with contaminated air.
Rowan (Mountain Ash) Trees
The Rowan tree is steeped in cultural mythology and practical uses, including medicinal, drink, food and ceremonial. Its shape, flowers and decorative fruit makes it a popular landscape choice.