Description of Alnus viridis ssp. sinuata
Alnus viridis ssp. sinuata is a small deciduous tree or shrub that belongs to the Betulaceae family. This plant is commonly known as Sitka alder, green alder, or Slide alder.
Origin
Alnus viridis ssp. sinuata is native to North America, particularly in Alaska and western British Columbia.
General Appearance
The Sitka alder plant can grow up to 20 feet tall. It has a narrow, oval-shaped crown and a single stem. The bark is thin and has a greenish-grey color. The leaves are dark green, glossy, and have a wavy edge. The male flowers are in the form of long, drooping catkins. While the female flowers are small, green, and rounded.
Uses
The Sitka alder plant is a popular choice for many native communities because it has a high cultural value. The tree was used by people living in the coastal region of North America to make dugout canoes, baskets, and clothing. The leaves and bark were boiled to make a medicinal tea to treat various illnesses. The plant is also used for erosion control and is a great restoration species for degraded habitats.
Growth Conditions for Alnus viridis (Vill.) Lam. & DC. ssp. sinuata (Regel) A.& D. Löve
Light Requirements: Alnus viridis ssp. sinuata requires full sunlight to partial shade to grow appropriately. In areas with full sunlight, the plant may prefer some shading during the hottest part of the day. On the other hand, excessive shading results in the plant's slow growth and poor quality.
Temperature Requirements: This plant can tolerate extreme temperatures. It grows well in areas with cool summers and cold winters. Its ability to withstand severe temperatures makes it suitable for planting even at high altitudes, mainly in the northern hemisphere. During hot weather, the plant may need extra watering to keep it from drying out.
Soil Requirements: Alnus viridis ssp. sinuata grows well in moist and well-drained soils. It can tolerate a wide range of soil types, ranging from sandy to loamy soils. The plant prefers soils that are rich in organic matter. It is essential to maintain the pH level of the soil between 6.0 and 7.5. For optimal growth, the plant requires regular watering, but it should not be waterlogged.
Nutrient Requirements: An adequate supply of nutrients is crucial for this plant to thrive. The plant requires a balanced nutrient supply, including nitrogen, phosphorus, and potassium. Nitrogen is essential for plant growth and foliage development, while phosphorus promotes root and stem growth. Potassium, on the other hand, helps the plant in stress tolerance and overall plant development.
Propagation: Alnus viridis ssp. sinuata can be propagated through seeds, cuttings, or suckers. Seeds should be sown in a well-prepared seedbed or germination tray. Cuttings should be taken from the parent plant and placed in rooting hormone before planting. Suckers should be removed from the parent plant and transplanted to a new location.
Cultivation of Alnus viridis (Vill.) Lam. & DC. ssp. sinuata (Regel) A.& D. Löve
Alnus viridis ssp. sinuata, commonly known as Sitka alder, is a native shrub of North America. It can grow up to 16 feet (5 meters) tall and is hardy in USDA zones 2-7. It prefers moist soils and partial shade with open sun exposure. Sitka alder is an excellent choice for wetland restoration, erosion control and hedgerows.
Watering Needs
The Sitka alders do not require frequent watering once they are established, as they can develop deep root systems. However, during dry spells, it is necessary to water them regularly. In general, aim to provide an inch of water per week, especially in dry, hot weather. Watering should be done at the base of the plant, avoiding getting the leaves wet to prevent fungal diseases.
Fertilization
In general, mature Sitka alders do not need fertilization once they are established. However, young trees or those planted in nutrient-poor soil can benefit from fertilization. It is best to spread 0.5-1 pound of a balanced fertilizer with a 16-16-16 NPK ratio per year around the drip line of the tree. The best time to fertilize is in early spring, just before new growth begins.
Pruning
Sitka alders do not require extensive pruning, but you can control their shape and size with pruning. You can prune them to a single stem tree shape, or you can let them grow as multi-stemmed shrubs. Pruning is best done in late winter or early spring before the buds swell. Remove diseased, damaged, or crossing branches, and any dead wood. Try to space the branches evenly and thin as necessary to provide good air circulation. Remember not to prune more than one-third of the plant in a single year.
Propagation of Alnus viridis ssp. sinuata
Alnus viridis ssp. sinuata, commonly known as the green alder, is a deciduous shrub that belongs to the Betulaceae family. It is native to North America and is a popular plant amongst gardeners. Propagation of this plant can be done through various methods that are explained below.
Seed Propagation
Seed propagation is the most common method used to propagate Alnus viridis ssp. sinuata. The seeds need to be collected when they are fully ripe and have turned brown. They can be stored for up to two years and then sowed in a nursery bed during late summer or early fall. Before sowing, the seeds should be soaked in water for 24 hours. The soil in the nursery bed should be moist and well-draining. Germination can take up to six weeks.
Softwood Cutting Propagation
Softwood cutting propagation is another method used to propagate Alnus viridis ssp. sinuata. This method involves taking cuttings of the plant's softwood that are around 4-6 inches long. The cutting should be taken during late spring or early summer and should be planted in a well-draining soil mixture. The cutting should be kept moist and should be placed in a shaded area until roots form.
Division Propagation
Division propagation is a method used for mature shrubs. This propagation method involves dividing the plant's root ball into several sections, ensuring that each section has both roots and shoots. The divided sections should be replanted in soil that is moist and well-draining. Keep the plants moist and in a shaded area until they establish.
Grafting Propagation
Grafting propagation is a method used to propagate Alnus viridis ssp. sinuata with specific characteristics like disease resistance. This method involves fusing a scion (a small branch with buds) to a rootstock. The scion should be grafted onto the rootstock during late winter or early spring. The grafted plant should be kept in a moist and shaded area until the graft has grown and is established.
Disease Management
Alnus viridis ssp. sinuata is commonly affected by a few diseases that affect its growth and yield. One of the most common diseases is leaf spot, which is caused by the fungus Mycosphaerella alni. This disease manifests as small dark brown spots on the leaves. The fungus can cause defoliation, leading to reduced growth and yield. To manage this disease, it is recommended to prune the affected leaves and avoid overhead watering. Fungicides can also help control the disease.
Another disease that affects Alnus viridis ssp. sinuata is canker, which is caused by the fungus Nectria galligena. The disease leads to the formation of sunken lesions that ooze sap. Cankers can weaken the tree and cause girdling, which can be fatal. Infected branches should be pruned to prevent the disease from spreading. Fungicidal sprays can also help control the disease.
Pest Management
Alnus viridis ssp. sinuata is vulnerable to a number of pests that can cause significant damage to the plant. One common pest is the alder leaf beetle (Agelastica alni), which feeds on the foliage of the plant, leading to defoliation. This can reduce growth and yield. To manage this pest, it is recommended to use insecticidal sprays or introduce natural predators such as parasitic wasps or ladybugs.
The European spruce bark beetle (Ips typographus) can also affect Alnus viridis ssp. sinuata. This beetle burrows into the bark of the tree, disrupting the flow of nutrients and water. This can lead to the death of the tree. To manage this pest, it is recommended to keep the tree healthy and prevent stress by avoiding overwatering or fertilization. Trees that are already infected should be removed and destroyed to prevent the spread of the pest.
