Overview
Braya alpina Sternb. & Hoppe var. americana (Hook.) S. Wats. is a low-growing, perennial flowering plant belonging to the family Brassicaceae. It is commonly known as American alpine-cress and is widely distributed across the Arctic region of North America.
Appearance
The plant grows up to 10 cm tall and has multi-branched stems that spread out over the ground's surface. The leaves are small and are distributed along the stem alternately. They are usually elliptical or oblanceolate and measure up to 5 cm long and 1 cm wide. The flowers are small, white, and measure about 2 mm in diameter. They are arranged in clusters at the top of the stem. The fruit is a narrow and a long pod containing small, brown seeds.
Origin
American alpine-cress is native to the Arctic region of North America and can be found in Alaska, Greenland, and northern Canada. It is well adapted to the harsh conditions of the mountain tundra and can survive in cold, dry, and nutrient-poor soils.
Uses
American alpine-cress is an important food source for the indigenous people living in the Arctic region. The leaves and flowers are edible and are consumed fresh or dried. They are used as a seasoning for meat and fish dishes or added to salads and soups. The plant is also used for medicinal purposes to treat various ailments such as chest congestion, coughs, and colds.
Light Requirements
The typical growth conditions for Braya alpina var. americana include exposure to moderate to high levels of sunlight. The plant tends to grow best in areas with full sun to partial shade. In areas with a hot climate, Braya alpina var. americana may benefit from some shade during the hottest part of the day to prevent sunburn.
Temperature Requirements
The plant is adapted to grow in subarctic and alpine tundra environments, where temperatures remain cool throughout the year. Braya alpina var. americana can tolerate relatively low temperatures and is known to grow at around 0°C. The ideal temperature range for growth is between 10°C and 20°C. At temperatures above 25°C, growth slows down and can cause damage to the plant.
Soil Requirements
The plant prefers well-drained, alkaline to neutral soils that are not too fertile. It can grow in a wide range of soil types, including sandy, loamy, and clay soils. However, it requires adequate moisture for growth, and waterlogging should be avoided. In addition, the plant is adapted to grow in soils with low nutrient availability, and too much fertilizer can be detrimental to its growth.
Cultivation Methods
Braya alpina Sternb. & Hoppe var. americana (Hook.) S. Wats. is a cold-loving plant that grows best in the polar tundra. It prefers moist soil and full sun exposure. It can grow in various types of soils but thrives in well-draining soil. The plant can be grown from seeds or propagated through cuttings. If planting from seeds, they should be sown in the fall in a cold frame or greenhouse.
Watering Needs
The plant prefers moist soil, but be careful not to overwater, as it can cause the plant to rot. During the growing season, water the plant regularly, but ensure that the soil is not waterlogged. In winter, the plant requires little to no water, and it can tolerate drought conditions.
Fertilization
Braya alpina Sternb. & Hoppe var. americana (Hook.) S. Wats. is adapted to growing in nutrient-poor soils, so it does not require much fertilizer. Fertilization should be done in moderation, and it's advised to use slow-release fertilizers. Organic fertilizers such as compost or manure can be used, but it should be worked into the soil before planting.
Pruning
The plant does not require much pruning. However, if the plant becomes leggy, it can be pruned back to encourage bushy growth. Dead or damaged parts of the plant should be removed to prevent the spread of diseases.
Propagation of Braya alpina Sternb. & Hoppe var. americana (Hook.) S. Wats.
Propagation of Braya alpina Sternb. & Hoppe var. americana (Hook.) S. Wats. can be achieved through a variety of methods. Some common propagation methods include:
Seed Propagation
The easiest way to propagate Braya alpina Sternb. & Hoppe var. americana (Hook.) S. Wats. is through seed propagation. The seeds should be collected from the plant when they are fully matured. They should be stored in a cool and dry place until ready for planting. Before planting, the seeds should be stratified for a few weeks at a time to simulate winter-like conditions. This will help to break dormancy and promote germination. Once ready, plant the seeds in a soil mix that is well-draining and keep the soil moist until germination.
Division Propagation
Another propagation method for Braya alpina Sternb. & Hoppe var. americana (Hook.) S. Wats. is through division. This method is best done in the spring or fall when the plant is not actively growing. The plant should be dug up carefully and the root system should be divided into smaller portions. Each portion should have a healthy root system and a top. Replant the divided portions in well-draining soil and water thoroughly.
Cutting Propagation
Cutting propagation is a more difficult method of propagation and requires rooting hormone and good care. Take cuttings of the plant in the spring or in early fall. The cuttings should have a few leaves and a few inches of stem. Dip the cuttings in rooting hormone and place in a well-draining soil mix. Keep the soil moist and wait for the cutting to root. This process can take several months.
Disease Management
Braya alpina Sternb. & Hoppe var. americana (Hook.) S. Wats. is highly susceptible to some diseases, including:
- Leaf Spot: This disease manifests as circular spots on the leaves, which turn yellow and then brown. It is caused by the fungus Phoma sp. and can be managed by pruning infected leaves and using fungicides.
- Rust: This disease appears as orange or brown pustules that occur on the undersides of leaves. It is caused by the fungus Puccinia monoica and can be managed by removing affected leaves and using fungicides.
- Pythium Root Rot: This fungus infects the roots of the plant, causing them to turn brown and rot. It can be managed by ensuring adequate drainage and using fungicides.
Pest Management
Braya alpina Sternb. & Hoppe var. americana (Hook.) S. Wats. is also vulnerable to pest infestations, including:
- Root Maggots: These are the larvae of the Delia brassicae fly and feed on the roots of the plant. Infested plants may wilt and die. They can be managed by using insecticides or by introducing parasitic wasps.
- Aphids: These small insects feed on the sap of the plant, causing the leaves to curl and turn yellow. They can be managed by using insecticidal soap or introducing natural predators such as ladybugs.