General Appearance
Astragalus emoryanus (Rydb.) Cory var. terlinguensis (Cory) Barneby, commonly known as Terlingua milk-vetch, is a herbaceous perennial plant belonging to the family Fabaceae. This plant can grow up to a height of 1-2 feet and has a bushy appearance. It has slender, wiry stems that arise from a woody base.
Origin and Distribution
The genus astragalus has more than 2,000 species. Astragalus emoryanus (Rydb.) Cory var. terlinguensis (Cory) Barneby is native to the southwestern region of the United States and northern Mexico. It is found in the Chisos Mountains of West Texas, Big Bend National Park, and the Rio Grande region and is a rare and endangered plant species.
Common Names
The Astragalus emoryanus (Rydb.) Cory var. terlinguensis (Cory) Barneby is commonly known as Terlingua milk-vetch due to its occurrence in the Terlingua Creek drainage area near the border of Texas and Mexico.
Uses
Astragalus emoryanus (Rydb.) Cory var. terlinguensis (Cory) Barneby has several medicinal uses. The dried root of the plant is known to have anti-diabetic and anti-inflammatory properties. The plant also contains flavonoids and saponins such as astracoside and astragalosides that help in controlling diabetes and reducing inflammation in the body. This plant is also used as an ornamental plant in gardens for its beautiful flowers and foliage.
Light Requirements
Astragalus emoryanus var. terlinguensis requires full sunlight exposure for optimal growth and development. It is intolerant to shaded environments and may even die if it receives less than six hours of direct sunlight per day.
Temperature Requirements
This plant is native to the Chihuahuan Desert and can withstand a wide range of temperature fluctuations. It grows best in warm temperatures that range from 60 to 95 degrees Fahrenheit during the day. Nights may get cooler but should not go below freezing temperatures. The plant will go dormant during the winter months when the temperature drops below 40 degrees Fahrenheit.
Soil Requirements
Astragalus emoryanus var. terlinguensis is adapted to soils with low fertility and good drainage. It prefers rocky soils that are well-drained and can tolerate soils with low pH levels. It grows best in soils that are slightly acidic, with a pH ranging from 5.5 to 7.0. The plant is sensitive to water-logged soils and may suffer from root rot if planted in heavy clay soils.
Cultivation
Astragalus emoryanus (Rydb.) Cory var. terlinguensis (Cory) Barneby grows well in well-draining soil with a pH between 6.0 to 7.5. It thrives in full sun and is drought resistant, making it a perfect choice for hot and dry environments. It is best planted in the spring or fall when the temperatures are cooler and soil moisture is adequate.
Watering Needs
Astragalus emoryanus (Rydb.) Cory var. terlinguensis (Cory) Barneby has low to moderate water requirements. Watering should be done once a week during the growing season and reduced in winter to prevent the plant from getting waterlogged. Overwatering can lead to root rot, weakening of the plant and eventual death.
Fertilization
Astragalus emoryanus (Rydb.) Cory var. terlinguensis (Cory) Barneby does not require heavy fertilization. A balanced fertilizer with a ratio of 10-10-10 can be applied once a month during the growing season. Alternatively, organic fertilizer can be used, as it provides a gradual release of nutrients and improves soil structure.
Pruning
Astragalus emoryanus (Rydb.) Cory var. terlinguensis (Cory) Barneby does not require pruning, except for the removal of dead or diseased parts of the plant. This should be done early in the growing season to encourage healthy growth and prevent the spread of disease. Over pruning can weaken the plant and impact its future flowering.
Propagation of Astragalus emoryanus var. terlinguensis
Astragalus emoryanus var. terlinguensis is a perennial herbaceous plant that is native to the Southwestern United States and Northern Mexico. Propagation of this plant can be done by both seed and vegetative methods.
Seed Propagation
Seeds of A. emoryanus var. terlinguensis can be sown directly into the soil in the fall or early spring. It is important to scarify the seeds by rubbing them between a fine grit sandpaper to break down the tough outer layer. Soaking the seeds in water for 24 hours before planting can also help with germination. The seeds should be planted 1/8 to 1/4 inch deep in well-drained soil in a location with full sun exposure.
Keep the soil consistently moist until germination which can take up to three weeks. Once the seedlings have grown to a height of about 2 inches, thin them to about 12 inches apart. A. emoryanus var. terlinguensis is a slow-growing plant, and it may take up to three years for it to reach maturity and begin to flower.
Vegetative Propagation
A. emoryanus var. terlinguensis can also be propagated vegetatively through cuttings. Cuttings should be taken in the early spring before flowering, and should be about 3 to 4 inches long. The cuttings should be taken from new growth and should have at least one leaf node.
The cuttings should be planted in well-drained soil in a location with full sun exposure. Cover the cuttings with plastic to create a humid environment and mist them regularly to keep the soil moist. Once the cuttings have developed roots, which can take up to two months, the plastic covering can be removed.
Transplant the new plants to a permanent location once they have reached a height of 2 to 3 inches and have developed several leaves. It is important to keep the plants well-watered during the first year after transplanting to ensure their survival.
Disease and Pest Management for Astragalus emoryanus (Rydb.) Cory var. terlinguensis (Cory) Barneby
Astragalus emoryanus (Rydb.) Cory var. terlinguensis (Cory) Barneby is a hardy plant that is generally disease and pest resistant. However, like all plants, it is not entirely immune to pests and diseases. Here are some common diseases and pests that might affect the plant and suggestions for managing them:
Diseases
One of the most common diseases to affect A. emoryanus is root rot, which is caused by overwatering or poorly-draining soil. To avoid root rot, make sure the plant is in well-draining soil and only water it when the soil is dry to the touch. Another common disease is rust, which causes orange or yellow spots on leaves. Remove any affected leaves to prevent the spread of rust. Powdery mildew is also a potential problem. This fungus will cause white, powdery spots on leaves and can be treated with anti-fungal sprays. Avoid overhead watering and make sure plants have good air circulation to prevent powdery mildew.
Pests
Although not common, aphids, spider mites, and thrips can occasionally be a problem for A. emoryanus. Inspect the plant regularly for any signs of these pests. If detected, isolate the plant to prevent the pests from spreading to other plants. Aphids and spider mites can be treated with insecticidal soap or neem oil, while thrips can be controlled with a systemic insecticide. Be sure to follow the instructions on the product you choose and use caution when applying any chemicals to the plant.
As with all plants, the best way to prevent disease and pests from affecting A. emoryanus is to provide it with good growing conditions, including proper sunlight, watering, and fertilization. Regular maintenance, such as pruning and removing dead leaves, can also help prevent disease and pests from taking hold. By following these tips, you can help ensure a healthy and thriving plant.
