Overview
Astragalus strigosus Coult. & Fisher, commonly known as silky milkvetch, is a herbaceous plant native to North America. It is a member of the Fabaceae family and is known for its medicinal properties.
Appearance
The silky milkvetch is an erect, bushy perennial herb that can grow up to 0.3 to 1 m tall. It has a single stem, covered with fine hairs and is often branched at the base. Its leaves are pinnately compound, with 10-18 leaflets, and have a silky or hairy texture. The flowers are spurred and arranged in racemes of 10-25, each about 12-15 mm long and ranging in color from yellow to cream.
Origin
Astragalus strigosus Coult. & Fisher is native to North America and can be found in various habitats, including meadows, prairies, and open woodlands. It is known to grow in the western United States, Canada, and Mexico, ranging from British Columbia and Alberta to California and New Mexico.
Common Names
The plant is commonly known as silky milkvetch, silky locoweed, and silky astragalus.
Uses
Astragalus strigosus Coult. & Fisher has long been used by traditional herbalists for its medicinal properties. It contains several bioactive compounds, including flavonoids, saponins, and polysaccharides, which are believed to have immune-boosting, anti-inflammatory, and antioxidant properties.
It has traditionally been used to treat various ailments, including common cold, flu, upper respiratory infections, and allergies. Furthermore, this plant is also useful against eczema, psoriasis, dermatitis, and other skin inflammations.
Today, Astragalus strigosus Coult. & Fisher is widely used in dietary supplements, teas, and topical creams for its various health benefits.
Light Requirements:
Astragalus strigosus Coult. & Fisher typically grows in full sunlight to partial shade. In areas with hot climates, it may benefit from some shade during the hottest part of the day.
Temperature Requirements:
Astragalus strigosus Coult. & Fisher grows best in moderate temperatures. It can tolerate some freezing temperatures, but it prefers warmer temperatures ranging from 48–82°F (9–28°C).
Soil Requirements:
Astragalus strigosus Coult. & Fisher prefers well-draining soils. It can tolerate a range of soils, including those that are sandy, loamy, or gravelly. However, it does not grow well in heavy clay soil. The plant does not tolerate salty or waterlogged soils and prefers a pH range of 6.0–7.5.
Cultivation Methods
The Astragalus strigosus Coult. & Fisher grows well in dry and sandy soils. To plant it, scatter the seeds ‘in situ’ after collecting them into a paper bag once the pods ripen. The best time to plant is during early spring when soil temperature and moisture levels are favorable. Cover the seeds with a light layer of soil, but do not bury them deep in the ground. The plant requires light to germinate; therefore, avoid covering the seeds with too much soil. Once the seedlings grow, thin them out to a spacing of 9-12 inches apart to allow room for each plant's root system.
Watering Needs
Astragalus strigosus Coult. & Fisher is drought-tolerant; however, irrigation is necessary during dry spells. Watering should be light, frequent, and done early in the morning, ensuring that the soil does not remain waterlogged. Too much water can damage the roots, leading to root rot and susceptibility to pests and diseases.
Fertilization
Astragalus strigosus Coult. & Fisher does not require fertilizer. The plant can fix nitrogen naturally and is thus well equipped to cope with nutrient-poor soils. However, a slow-release organic fertilizer applied during the plant's establishment phase can help provide nutrient requirements. Avoid using synthetic fertilizers as they can cause damage to the plant and surrounding soil.
Pruning
Pruning is not a requirement for the Astragalus strigosus Coult. & Fisher. However, deadheading the plant after flowering is recommended to prevent it from self-sowing. This process can also enhance extended blooming periods and keep the plant compact. Remove any wilted, yellow, or damaged branches during the growing season to enhance airflow and ensure good health and aesthetics of the plant.
Propagation of Astragalus strigosus Coult. & Fisher
Astragalus strigosus, commonly known as the "rough-stemmed milkvetch," can be propagated both through seeds and cuttings.
Seed Propagation
The ideal time to collect the seeds of Astragalus strigosus is when the pods have turned brown and are dry. Collect the seeds and store them in a cool and dry place until you are ready to plant them.
To increase the germination rate, it is recommended to scarify the seeds using sandpaper or by soaking in boiling water for a few seconds. After scarification, sow the seeds in a seed-starting mix and cover them with a light layer of soil. Water them lightly and keep them in a warm and bright spot, but not in direct sunlight.
The seeds will germinate in 2-3 weeks, and the young seedlings can be transplanted to individual containers for a few months before planting them in the garden.
Propagation from Cuttings
Astragalus strigosus can also be propagated from stem cuttings taken in early summer. Take a stem cutting approximately 4-6 inches long from a healthy and mature plant. Cut off the bottom leaves and dip the cut end in rooting hormone powder.
Plant the cutting in a pot filled with seed-starting mix, keeping the soil moist but not waterlogged. Cover the pot with a plastic bag and keep it in a warm and bright spot but not in direct sunlight. Remove the plastic bag after 3-4 weeks when the cutting starts to grow new leaves.
When the cutting has developed a strong root system in a few months, transplant it to a larger pot or directly into the garden.
Disease and Pest Management for Astragalus strigosus Coult. & Fisher Plant
Astragalus strigosus Coult. & Fisher, commonly known as annual milkvetch, belongs to the Fabaceae family. It is an herbaceous plant that is native to the United States and can be found in most states. The following are some common diseases and pests that might affect the plant and ways to manage them.
Diseases
The common diseases that might affect Astragalus strigosus Coult. & Fisher are:
- Root Rot: This disease is caused by a fungus that attacks the roots of the plant. The plant appears wilted, and the leaves turn yellow. To manage this disease, it is recommended to avoid overwatering the plant and to ensure proper drainage of the soil. Fungicides can also be applied to manage this disease.
- Powdery Mildew: This disease is caused by a fungus that results in the plant's leaves becoming coated with a powdery substance. To manage this disease, it is recommended to prune infected foliage, remove all plant debris, provide proper air circulation, and apply fungicides.
- Rust: This disease is caused by a fungus that results in the formation of yellow or orange pustules on the plant's foliage. To manage this disease, it is recommended to identify the disease early and remove infected foliage. Fungicides can also be applied to manage this disease.
Pests
The common pests that might affect Astragalus strigosus Coult. & Fisher are:
- Aphids: These are small insects that feed on the plant's sap, resulting in the plant appearing weak and stunted. To manage aphids, it is recommended to spray the plant with a jet of water or apply insecticidal soap.
- Spider Mites: These pests are tiny insects that feed on the plant's sap, resulting in the leaves turning yellow or brown. To manage spider mites, it is recommended to spray the plant with a jet of water or apply insecticidal soap.
- Thrips: These are tiny insects that suck the plant's sap, resulting in bud drop and leaf curling. To manage thrips, it is recommended to remove all weeds from the surrounding area, spray the plant with neem oil, or apply insecticidal soap.
It is recommended to monitor the plant regularly for any signs of diseases or pests and take appropriate measures to manage them. Early identification and management of diseases and pests can help ensure the plant's healthy growth and development.
