Where do alder trees grow best?
Alder grows along rivers and on wetlands. In fact, it thrives anywhere where the ground is damp. The roots of the alder often help to stabilise the riverbank and prevent the soil from being washed away.
What climate do alder trees grow in?
Red alder grows in climates varying from humid to superhumid. Annual precipitation ranges from 400 to 5600 mm (16 to 220 in); most of the precipitation is rain in winter. Summers are generally cool and dry. Temperature extremes range from -30° C (-22° F) in Alaska and Idaho to 46° C (115° F) in California.
Do alder trees grow near water?
Alder trees do best in the cool damp soil found near the freshwater of rivers, streams, ponds and marshes. A long line of alder trees is a very strong sign of a river or stream. A dense clump of them is more likely a pond or boggy area. A wide expanse of alders indicates marshland or damp woodland.
What is special about alder trees?
The most notable features of all varieties of alder trees are their catkins and strobiles. Both male and female flowers (catkins) appear on the trees. As a monoecious species, alders self-pollinate. Female flowers begin developing as small, round green growths in the summer or fall before the next spring's bloom.
Is alder poisonous to dogs?
Alnus glutinosa has no toxic effects reported.
Is alder wind tolerant?
Alders will tolerate most conditions, including sea air and swampy conditions, and with their fast-growing habit they're a perfect tree for wind breaks, privacy and shelter.
What is the lifespan of an Alder tree?
Typically living less than 100 years, alder has a relatively short lifespan. So compared to other pioneer species like Douglas fir, which can often live to be 600 years old or more, alder is the “live fast, die young” tree of Pacific Northwest forests.
Will alder grow in dry soil?
- However, the Alder will also grow at elevations up to 500 metres in any soil type and it will enrich the soil with nitrogen as it grows. - They are not generally recommended for planting in dry, sandy situations as they are prone to dieback and have limited growth potential.
Do bees like alder?
Trees such as hazel, alder and willow provide early sources of pollen, important food for queen bees to allow her to start egg laying early in the year.
Do birds like alder trees?
Red alder is an excellent nitrogen fixer and good for reclaiming bare land; it also grows in poor soil, as long as the soil is moist. This tree can provide habitat for a wide range of songbirds, such as warblers, chickadees, sparrows, finches, wrens, and vireos.
Do alder trees fall easily?
It is normal far small, and even fairly large, branches to die and drop, especially in alders. Healthy trees rarely just up and fall over, but a bad storm or combination of weather events can knock even a healthy tree over.
Do alder trees have deep roots?
The root system of red alder is shallow and spreading where limited by poor drainage; a deep-root system develops on soils with better drainage. The range of red alder extends from southeastern Alaska (lat 60°N) to southern California (lat 34°N), generally within 125 miles of the ocean.
Where are alder found?
Its natural habitat is moist ground near rivers, ponds and lakes and it thrives in damp, cool areas such as marshes, wet woodland and streams where its roots help to prevent soil erosion. It can also grow in drier locations and sometimes occurs in mixed woodland and on forest edges.
Is alder wood weather resistant?
A Durable Hardwood Alder is well known for its use in boats and sluice components. As an exterior door, alder will withstand all manner of weather for decades and requires very little maintenance.
Will alder grow in dry soil?
- However, the Alder will also grow at elevations up to 500 metres in any soil type and it will enrich the soil with nitrogen as it grows. - They are not generally recommended for planting in dry, sandy situations as they are prone to dieback and have limited growth potential.
Where do alder trees grow Europe?
The European alder is a loose to well-branched medium-sized deciduous tree that lives in Central Europe at altitudes of 1.200 meters (4000 ft) and in the Engadin sporadically also at altitudes up to 1.800 meters (5900 ft) can be found.
What is the purpose of catkins?
The catkins of some alder species have a degree of edibility, and may be rich in protein. Reported to have a bitter and unpleasant taste, they are more useful for survival purposes. The wood of certain alder species is often used to smoke various food items such as coffee, salmon, and other seafood.
What is the bark of Venice made of?
Most of the pilings that form the foundation of Venice were made from alder trees. Alder bark contains the anti-inflammatory salicin, which is metabolized into salicylic acid in the body. Some Native American cultures use red alder bark ( Alnus rubra) to treat poison oak, insect bites, and skin irritations.
Why are alder leaves important?
glutinosa and A. viridis are classed as environmental weeds in New Zealand. Alder leaves and especially the roots are important to the ecosystem because they enrich the soil with nitrogen and other nutrients.
Why are red alders beneficial?
As a result of this mutually beneficial relationship, alder improves the fertility of the soil where it grows, and as a pioneer species, it helps provide additional nitrogen for the successional species to follow. A red alder seed is a tiny samara like those of all alders.
What are the first species to colonize disturbed areas from floods, windstorms, fires, landsl?
Alders are common among the first species to colonize disturbed areas from floods, windstorms, fires, landslides, etc. Alder groves often serve as natural firebreaks since these broad-leaved trees are much less flammable than conifers.
How tall is a red alder?
glutinosa ), native to most of Europe and widely introduced elsewhere, both reaching over 30 m (98.42 ft). By contrast, the widespread Alnus alnobetula (green alder) is rarely more than a 5-metre-tall (16-foot) shrub.
How much nitrogen does red alder produce?
Red alder stands have been found to supply between 130 to 320 kilograms per hectare (120 to 290 pounds per acre) of nitrogen annually to the soil.
What is the relationship between alder and Frankia alni?
Alder has an important symbiotic relationship with a bacterium called Frankia alni. Frankia forms nodules on the tree’s roots and live within the nodules. This nitrogen-fixing bacterium absorbs nitrogen from the air and makes it available to the tree.
Why is alder important to fish?
As a deep-rooted species, it helps to maintain the soil in river banks and reduces the effects of erosion. Alder root systems which are exposed in the water can give shelter to fish and provide a safe refuge from predators. Alder foliage provides shade which is beneficial to fish , including salmon and brown trout.
How does alder help the bacterium?
Alder, in turn, provides the bacterium with carbon, which it produces through photosynthesis. This relationship allows alder to improve the fertility of the soils where it grows. As a pioneer species, it helps provide nutrients for the successional species which follow.
How big are alder buds?
The buds are 7 mm. in length. Alder is deciduous, and the new leaves open out in April. They are up to 10 cm. in size with a waved margin and are almost circular in shape. Sometimes they have a notch at the apex, and they taper to a slight point on the leaf stem.
What is the color of alder bark?
Alder bark is dark grey and fissured, while the young branches are smooth and greenish in colour. Branches are ascending in their growth form, and trees with two or three main trunks are common. The twigs are sometimes sticky to the touch.
Why is alder important to the Caledonian Forest?
Because it is the most common tree in riparian woodlands, which often form the ecological linkages between different forest patches, alder is an important species in the Caledonian Forest. Its survival and expansion is essential to the health of the land and rivers alike.
How tall is an alder tree?
Alder is a member of the birch family of trees, Betulaceae. It can reach 30 metres in height, although in Scotland it is rarely more than 20 metres tall. Like the birches, it is a pioneer species which grows quickly and is relatively short-lived. It can live to around 150 years old.
What is the difference between birch and alder?
Alder trees are related to birch trees ( Betula ). The difference between alders and birches is their cones. Alder female flowers become woody conical cones that turn brown during the fall.
How to identify an alder tree?
Alder trees are easily identified by their brown hard, cone-like strobiles that dangle from bare brown-purple twigs that have orange markings. You can also spot alder trees by their light gray bark and orange-brown drooping flowers. Another identifying feature of the alder trees is their pointed egg-shaped green leaves with serrated edges.
What is the difference between a male and female alder tree?
Alder Tree Flowers. Alder male flowers (catkins) are long and slender whereas the female flowers turn to woody round cones (strobiles) An alder tree flower is a type of slender, conical flower cluster called a catkin. Alders are also monoecious trees—meaning they have male and female flowers on the same tree.
How tall is a red alder tree?
Its spreading branches create a conical shape with a slender, rounded crown. Red alder trees grow between 66 and 100 ft. (20 – 30 m) tall. The red alder tree is the largest in the genus Alnus.
What are the leaves on an alder tree?
Generally, alder tree leaves are egg-shaped blades with a central vein and parallel veins from the midriff to the serrated leaf edge. Some alder tree leaves have toothed edges and pointed tips, whereas others are rounded and smooth.
How long do alder trees live?
Generally, alders are fast-growing trees that live between 60 and 70 years. However, some alder trees live for up to 100 years.
How big do alder trees get?
Alder ( Alnus) is a genus of flowering deciduous trees in the family Betulaceae. There are about 35 alder species, comprising of large trees and smaller shrub-like trees. Many species of alders grow between 66 and 100 ft. (20 – 30 m) tall.
How do alder trees get their seeds?
The female flowers get pollinated by the wind and develop in small cone-like fruits. The fruits mature during the winter and come spring they open up and release their seeds into the wind. The fruits of the alder tree are not edible. They are nothing but wood cases full of seeds.
Why is alder oil used in herbal medicine?
Traditional Medicine: People into herbal medicine have always used alder oil to treat various ailments including diarrhea, muscle aches, and nausea. The heart-shaped leaves also offer relief to skin diseases.
How many different types of alder trees are there?
Alder Tree Varieties. Alder trees come in eight different species. Which variety you end up growing depends on your location, weather conditions, and how much space you have in your garden or lawn. Here are some of the most common alder varieties.
Why do alder trees have holes in their leaves?
Still, the leaf beetle feeds on and makes large holes in the leaves of the tree.
How long do alder trees live?
Known to live up to 60 years on average, the alder tree’s sense of secrecy hasn’t abated over time. Even in this day and age where the tree is most likely to be grown for its fine wood, one can’t help but get a mystical feeling when being around this giant tree.
What is the alder tree?
Steeped in mythology and folklore, the alder tree is formidable and awe-inspiring any way you look at it. Not the kind of tree too afraid to get its feet wet, the alder has been a permanent fixture of swamps, streams, and rivers. So it’s no wonder it has always been associated with mysteries and fairy tales in different cultures throughout the ages.
Why would people grow alder trees?
If neither the flowers of the alder tree are beautiful or fragrant nor the fruits edible, why would people grow these trees in the first place? Well, for one thing, they have top quality wood. And did we mention that humans, omnivores as they are, have found ways to add parts of the tree to their menu? Here are some common and historical uses of the alder tree.
What is an alder tree?
A good plant for establishing along stream banks to stabilize soil and add interest , alder can also be used as a specimen in a more formal landscape where wet soil challenges most other plants. It can be pruned to one central leader or used as a multi-stemmed specimen. Branches on central-leadered trees form attractive horizontal layers unlike most other trees. Similar to the dogwoods in this respect. Unfortunately, it is usually not grown in nurseries, but nursery operators should be encouraged to grow this adaptable tree.
How tall do common alder trees grow?
A popular tree of moist to wet soils, common alder is a moderate- to fast-growing (two feet per year) deciduous tree that usually grows to 40 to 50 feet in height with a 20- to 40-foot spread and a 12 to 18-inch trunk but is capable of reaching 80 feet in height in the woods. It is not native but has escaped from cultivation and will form pure stands or thickets in disturbed wet sites. Pyramidal when young, common alder often has multiple stems, making it ideal for use as a screen or specimen, the trees eventually becoming more rounded or oval as they mature. The two- to four-inch-wide, dark green, roundish leaves with toothed edges and pale undersides are joined in spring by rather insignificant male and female flowers. Foliage remains green well into the fall. It is the fruits that are most interesting—small, nutlike, one-inch "cones" that persist throughout the fall and winter, long after the darkening leaves have fallen. These fruits, along with the attractive, dark brown, furrowed bark and multi-stemmed growth habit, make common alder an attractive landscape specimen throughout the winter. The fruits are food for a variety of wildlife.
Can common alders grow in shade?
Common alder will grow easily in full sun or partial shade in almost any landscape setting since the tre es are able to "fix" nitrogen, or take it out of the soil atmosphere, enabling these trees to grow in the poorest and wettest soils where other trees might fail. Common alder will grow best in wet or moist soils, acid or alkaline, and have even been observed growing with roots submerged in water, but it is also tolerant of moderate drought, compaction, and urban stress. Common alder transplants easily and will seed itself into an area, creating a thicket if it is planted and left alone in an area that is not maintained.
Is powdery mildew serious?
Powdery mildew and cankers, but these are usually not serious.
Overview
Alders are trees comprising the genus Alnus in the birch family Betulaceae. The genus comprises about 35 species of monoecious trees and shrubs, a few reaching a large size, distributed throughout the north temperate zone with a few species extending into Central America, as well as the northern and southern Andes.
Description
With a few exceptions, alders are deciduous, and the leaves are alternate, simple, and serrated. The flowers are catkins with elongate male catkins on the same plant as shorter female catkins, often before leaves appear; they are mainly wind-pollinated, but also visited by bees to a small extent. These trees differ from the birches (Betula, another genus in the family) in that the female c…
Taxonomy
The genus is divided into three subgenera:
Trees with stalked shoot buds, male and female catkins produced in autumn (fall) but stay closed over winter, pollinating in late winter or early spring, about 15–25 species, including:
• Alnus acuminata Kunth – Andean alder, aliso. Mexico, Central and South Ame…
Ecology
Alders are commonly found near streams, rivers, and wetlands. Sometimes where the prevalence of alders is particularly prominent these are called alder carrs. In the Pacific Northwest of North America, the white alder (Alnus rhombifolia) unlike other northwest alders, has an affinity for warm, dry climates, where it grows along watercourses, such as along the lower Columbi…
Uses
The catkins of some alder species have a degree of edibility, and may be rich in protein. Reported to have a bitter and unpleasant taste, they are more useful for survival purposes. The wood of certain alder species is often used to smoke various food items such as coffee, salmon, and other seafood.
Most of the pilings that form the foundation of Venice were made from alder trees.
Culture
Ermanno Olmi's movie The Tree of Wooden Clogs (L' Albero Degli Zoccoli, 1978) refers in its title to alder, typically used to make clogs as in this movie's plot.
Further reading
• Chen, Zhiduan; Li, Jianhua (2004). "Phylogenetics and Biogeography of Alnus (Betulaceae) Inferred from Sequences of Nuclear Ribosomal DNA ITS Region". International Journal of Plant Sciences. 165 (2): 325–335. doi:10.1086/382795. S2CID 85579093.
External links
• Flora Europaea: Alnus
• Flora of Bolivia: Alnus
• Flora of China: Alnus
• Flora of North America: Alnus
• Flora of Pakistan: Alnus