Overview:
Alnus incana (L.) Moench var. occidentalis (Dippel) C.L. Hitchc. is a deciduous shrub or small tree that belongs to the Betulaceae family. The plant is commonly known as the Western Alder or Mountain Alder and is native to North America.
Appearance:
The Western Alder can grow to a height of 30 feet and has a rounded, bushy appearance. The bark is gray, smooth, and often has light-colored lenticels. The leaves are dull green, oval-shaped, and have a slightly toothed margin. The flowers are small and greenish-yellow, while the fruits are small, winged, and brown.
Uses:
The Western Alder has many uses. Native American tribes used the bark and leaves to make a variety of medicinal preparations to treat various ailments, such as diarrhea, fever, and colds. The plant is also important for wildlife, as it provides habitat and food for a variety of birds and mammals. The wood of the Western Alder is light and easy to work, making it a popular choice for furniture, veneer, and plywood.
In addition, the plant is used in riparian restoration projects to control erosion, improve water quality and provide shade. The Western Alder is also an important plant for land reclamation and has been used to reclaim areas that have been disturbed by mining or logging.
Light Requirements
Alnus incana var. occidentalis can tolerate a range of light conditions, from partial shade to full sun. However, it tends to thrive in areas with partial shade, as it can become stressed by intense direct sunlight. In the wild, it is commonly found growing under the canopy of larger trees.
Temperature Requirements
This plant can grow in a variety of temperature ranges, including cold and warm climates. It can tolerate winter temperatures as low as -50°F (-46°C) and summer temperatures up to 95°F (35°C). However, it grows best in cool to moderate temperatures with an average range between 50°F (10°C) and 70°F (21°C).
Soil Requirements
This plant can grow in a variety of soil types, including sandy loam, clay loam, and silty loam. However, it prefers moist and well-draining soil with a pH range of 6.0 to 7.5. It can tolerate soils that are slightly acidic or alkaline, but it may become stressed in extremely acidic or alkaline soils. In addition, it can grow in soils that are nutrient-poor and has the ability to fix nitrogen from the air.
Cultivation Methods
Alnus incana var. occidentalis is a cold-hardy and adaptable plant that can grow in a wide range of soil types, including clay, loam, and sandy soil. However, the plant thrives in well-drained soil with moderate moisture content. In addition to this, it is essential to plant the tree in an area that receives partial or full sunlight. To plant the tree, create a hole that is at least twice the width and depth of the root ball. Fill the hole with the soil mixed with compost, and then plant the tree. Water the tree thoroughly after planting to help it establish roots.Watering Needs
Alnus incana var. occidentalis requires frequent and regular watering, especially during its first year of growth. The best practice is to water the tree once a week, providing about one inch of water. However, the frequency of watering should reduce once the tree has established roots. It is essential to avoid overwatering the tree, as this can cause root rot.Fertilization
Alnus incana var. occidentalis does not require much fertilization. However, it can benefit from some nutrients from time to time. You can apply a slow-release fertilizer during the early spring or fall. However, it is essential to follow the manufacturer’s instructions for the right amount and method of application.Pruning
Pruning is an essential practice for maintaining the health and beauty of Alnus incana var. occidentalis. Pruning is best done in late winter or early spring before the tree starts to grow new shoots. The primary goal is to remove dead, broken, or diseased branches. Remove branches that grow close to the ground to provide clearance for pedestrians or lawn equipment. To prevent damage, use a sharp, clean pruning saw or shears to make clean cuts. Avoid cutting the branch collar, as this is the area where the branch connects to the tree and helps the wound heal. Finally, avoid pruning more than 20% of the tree’s canopy in a single pruning session.Propagation of Alnus incana var. occidentalis
Alnus incana var. occidentalis, commonly known as the mountain alder, is a deciduous shrub or small tree native to western North America. It is a hardy plant that can tolerate a wide range of growing conditions, making it a great choice for restoration projects.
Seed Propagation
The most common propagation method for Alnus incana var. occidentalis is from seeds. The seeds are best collected in the fall, as soon as they mature. They should be planted within a few weeks of collection.
Before planting, the seeds should be moist stratified for one to two months. This can be done by placing them in a plastic bag with some damp sawdust or vermiculite, and leaving them in the refrigerator. After stratification, the seeds can be planted in pots or directly into the ground at a depth of one to two inches.
Germination usually occurs within one to two months, and the young seedlings should be watered regularly.
Vegetative Propagation
Alnus incana var. occidentalis can also be propagated vegetatively, through techniques such as hardwood cuttings and root cuttings.
Hardwood cuttings should be taken in the winter, when the plant is dormant. Cuttings should be six to eight inches in length, and the lower end should be dipped in rooting hormone. They can then be planted in a well-draining potting mix and kept moist until they root, which usually takes several months.
Root cuttings should be taken in the fall, when the plant has started entering dormancy. They should be one to three inches in length, and planted horizontally in a potting mix. The cuttings should be kept moist, and should root within several weeks.
Overall, Alnus incana var. occidentalis is a relatively easy plant to propagate, and can be a great addition to restoration projects and native landscapes.
Disease and Pest Management for Alnus Incana (L.) Moench var. Occidentalis (Dippel) C.L. Hitchc.
Alnus incana (L.) Moench var. occidentalis (Dippel) C.L. Hitchc. is a deciduous shrub or small tree that is native to western North America. Like any other plant, this species is susceptible to various diseases and pests. Knowledge of the most common diseases and pests that might affect the shrub is essential in helping keep them in check. This knowledge also helps in planning a management strategy that aims to minimize the negative impact of the diseases and pests on the shrub. Below are some of the disease and pest management techniques that one can employ to manage the Alnus incana (L.) Moench var. occidentalis (Dippel) C.L. Hitchc. shrub.
Common Diseases
The Alnus incana (L.) Moench var. occidentalis (Dippel) C.L. Hitchc. shrub is susceptible to fire blight, which is a bacterial disease that causes wilting, blackening, and dying of the shoots, twigs, and leaves. Fire blight thrives in humid and warm weather conditions and can spread fast if not treated early. Crown gall is another disease that is caused by a bacterium that creates tumorous growths on the roots and stems of the plant, leading to stunted growth and yellowing of leaves. The pathogen thrives in soil, and its spread can be through contaminated tools and soil. Powdery mildew also affects the shrub, characterized by a white powdery coating on leaves and young twigs.
Common Pests
Spider mites, aphids, and sawflies are common pests that affect Alnus incana (L.) Moench var. occidentalis (Dippel) C.L. Hitchc. Spider mites thrive in hot and dry conditions, causing the leaves to take a stippled appearance, yellowing, and eventually wilting. Aphids, on the other hand, are small insects that suck sap from the plant's tender leaves causing yellowing, wilting, and stunted growth. Sawflies cause defoliation as they feed on the leaves hence stressing the plant.
Disease and Pest Management Techniques
There are various techniques that one can use in managing the diseases and pests that affect the Alnus incana (L.) Moench var. occidentalis (Dippel) C.L. Hitchc. shrub. The first step is maintaining proper sanitation practices by regularly pruning, removing, and disposing of infected plant parts. Sanitation also involves sterilizing tools, equipment, and soil before and after use to minimize the spread of pathogens. Applying fungicides and insecticides is another technique that one can use to manage the diseases and pests. There are organic and chemical options that one can explore depending on the severity of the infestation/problem. Following cultural practices such as watering the shrub regularly, applying a balanced fertilizer, and planting in well-drained soil helps in maintaining the shrub's overall health, making it less susceptible to pests and diseases.
In conclusion, the Alnus incana (L.) Moench var. occidentalis (Dippel) C.L. Hitchc. shrub, like any other plant, is susceptible to various diseases and pests. The best approach to managing them is being knowledgeable about the common diseases and pests, their control, and prevention strategies. Maintaining proper hygiene, cultural practices, the use of appropriate chemicals, and regular inspection are helpful in keeping the shrub healthy and robust.
