Origin
Astragalus mollissimus Torr. var. bigelovii (Gray) Barneby, also known as Bigelow's woollypod, is a perennial plant native to the southwestern United States, particularly in Arizona, California, and Nevada. It grows in various habitats, including dry washes, rocky slopes, and sandy or gravelly soils in desert scrub, pinyon-juniper, and sagebrush communities.
Common Names
Aside from being called Bigelow's woollypod, Astragalus mollissimus also goes by several other common names, such as woollypod milkvetch and soft-leaved milkvetch.
Uses
Astragalus mollissimus has been used for various purposes by Native Americans, such as the Hopi and Navajo tribes. Its roots were boiled and consumed as a tea to treat coughs, colds, fever, and other respiratory problems. It was also applied topically to treat skin eruptions and burns. Some tribes also used the plant's fibers to make cloth and baskets.
Today, Astragalus mollissimus is used as a forage plant for livestock and wildlife, as it provides a good source of protein and nutrients. It is also used for erosion control, soil stabilization, and reclamation of disturbed areas.
General Appearance
Astragalus mollissimus is a low-growing, spreading plant that can reach up to 1.5 feet in height. Its stems and leaves are covered in silky, grayish-white hairs, giving the plant a woolly appearance. The leaves are compound, with numerous small leaflets. The flowers are small and white or pinkish, clustered together in spikes at the end of the stem. The fruit is a hairy pod, containing several small seeds.
Light Requirements
Astragalus mollissimus Torr. var. bigelovii (Gray) Barneby requires full sun exposure for the majority of the day. This plant prefers bright sunlight and thrives in areas with at least six hours of direct sunlight per day. In areas with hot summers, it may benefit from some partial shade during the hottest parts of the day.
Temperature Requirements
This plant is native to desert regions, making it quite resilient to high temperatures. It is adapted to hot, dry, and arid conditions, making it ideal for growth in desert landscapes. The ideal temperature range for growth is between 45-100°F (7-38°C), with the optimal growth temperature at 70-90°F (21-32°C).
Soil Requirements
Astragalus mollissimus Torr. var. bigelovii (Gray) Barneby prefers well-draining soil with a pH range of 6.5-8.5. In its natural habitat, this plant grows in rocky, gravelly soils with minimal organic matter. It is tolerant of drought and can survive in sandy or rocky soil with low nutrient content. This plant is not tolerant of wet or poorly drained soils and may suffer from root rot if planted in an area with standing water.
Cultivation methods for Astragalus mollissimus Torr. var. bigelovii (Gray) Barneby
Astragalus mollissimus Torr. var. bigelovii (Gray) Barneby commonly known as Bigelow's woolly locoweed is a perennial shrub that requires full sun exposure and well-drained soils. It can tolerate a variety of soil types but prefers sandy or loamy soils with a pH range of 6 to 8.5. It can be grown from seeds or propagated by stem cuttings.
If growing from seeds, it is best to sow them in the fall or early winter. It is recommended to scarify the seeds by lightly scraping them with sandpaper or by soaking them in warm water for a few hours before planting. The seeds should be planted about 1/4 inch deep and kept evenly moist until germination.
If propagating by stem cuttings, take cuttings of 3 to 4 inches in length from healthy plants in the spring or early summer. Remove all leaves except for the top two, and dip the cuttings in rooting hormone before planting in well-draining soil. Keep the soil moist and out of direct sunlight until roots are established.
Watering needs for Astragalus mollissimus Torr. var. bigelovii (Gray) Barneby
Astragalus mollissimus Torr. var. bigelovii (Gray) Barneby requires moderate watering during the growing season. It is important not to overwater as it can lead to root rot. The plant should be watered deeply once a week or as needed, depending on weather conditions. It is recommended to allow the soil to dry out slightly between watering.
Fertilization for Astragalus mollissimus Torr. var. bigelovii (Gray) Barneby
Astragalus mollissimus Torr. var. bigelovii (Gray) Barneby does not require heavy fertilization. It is recommended to apply a balanced fertilizer in the spring as new growth appears. Alternatively, a slow-release fertilizer can be applied in the fall. It is important not to over-fertilize as it can lead to excessive foliage growth at the expense of flowers.
Pruning for Astragalus mollissimus Torr. var. bigelovii (Gray) Barneby
Astragalus mollissimus Torr. var. bigelovii (Gray) Barneby typically does not require heavy pruning. However, it can benefit from light pruning to maintain a tidy shape and encourage new growth. Dead or damaged branches should be removed as soon as possible. Light pruning should be done in the fall after flowering has finished.
Propagation of Astragalus mollissimus Torr. var. bigelovii (Gray) Barneby
Astragalus mollissimus Torr. var. bigelovii (Gray) Barneby, commonly known as Bigelow's woollybean or Bigelow's milkvetch, is a perennial herbaceous plant that belongs to the Fabaceae family. This plant is native to North America and is widely distributed in southern and western regions of the United States.
Propagation Methods
There are two primary methods for propagating Astragalus mollissimus Torr. var. bigelovii: seed propagation and vegetative propagation.
Seed Propagation
Seed propagation is the most common method for propagating Astragalus mollissimus Torr. var. bigelovii. Seeds of this plant can be collected in the fall when the seed pods have turned brown and brittle. The seeds should be stored in a cool and dry location until they are ready to be planted in the spring.
To prepare the seeds for planting, they should be scarified to increase the germination rate. Scarification can be done mechanically by lightly scratching the seed coat with sandpaper or a file, or chemically by soaking the seeds in hot water for a few hours. After scarification, the seeds should be planted in a well-draining soil mix and covered with a thin layer of soil. They should be kept moist and placed in a warm and bright location.
Germination of Astragalus mollissimus Torr. var. bigelovii seeds usually occurs within 1-2 weeks, although some seeds may take longer. Once the seedlings have developed their first true leaves, they can be transplanted into individual containers and grown until they are large enough to be planted outdoors.
Vegetative Propagation
Vegetative propagation of Astragalus mollissimus Torr. var. bigelovii can be done through division, cuttings, or layering.
Division involves separating the rhizomes or root clumps of the plant and planting them individually. This method works best in the spring when the plant is actively growing.
Cuttings can be taken from the stem of the plant in the summer. The cuttings should be treated with a rooting hormone and planted in a well-draining soil mix. They should be kept moist and placed in a warm and bright location until they develop roots and can be transplanted.
Layering involves bending a low-growing stem of the plant to the ground and covering it with soil. The stem will develop roots where it comes into contact with the soil and can be cut from the parent plant and transplanted once it has established a strong root system.
Disease Management
Astragalus mollissimus Torr. var. bigelovii (Gray) Barneby is relatively resistant to diseases. However, there are a few diseases that can affect the plant. Two common diseases that might affect this plant are root rot and powdery mildew.
Root Rot: This disease is caused by fungi that invade the plant's roots, causing them to rot. Plants infected with root rot may initially show stunted growth, wilting, and yellowing of leaves. To manage root rot, it is essential to remove the infected plants to prevent the spread of the disease. Fungicides like Thiophanate-methyl and Hexaconazole can also be applied to the soil surrounding the plant to prevent the fungi from attacking the roots.
Powdery Mildew: This disease is characterized by the presence of a white powdery substance on the leaves of the plant. This powdery substance is caused by fungi that attack the plant's leaves. To manage powdery mildew, it is essential to remove the infected leaves or plants as soon as possible. Fungicides such as sulfur or copper spray can also be used to control powdery mildew in the early stages of infestation.
Pest Management
The plant Astragalus mollissimus Torr. var. bigelovii (Gray) Barneby is also relatively pest-resistant. However, there are some pests that might attack the plant. The two common pests that might affect this plant are aphids and grasshoppers.
Aphids: These small insects suck sap from the plant, causing its leaves to curl and develop a yellowish appearance. In severe cases, aphids can stunt the growth of the plant. To manage aphids, natural predators such as ladybugs or parasitic wasps can be introduced to the garden. Alternatively, insecticidal soap or neem oil can be sprayed on the plant to kill the aphids.
Grasshoppers: These insects are particularly damaging to young plants as they eat the leaves and stems. In severe cases, grasshoppers can totally defoliate the plant, causing it to die. To manage grasshoppers, a physical barrier such as a mesh screen can be placed around the plant to prevent grasshopper infestation. Alternatively, chemical pesticides such as carbaryl or permethrin can be used to control the grasshoppers.
