Origin
Grindelia decumbens Greene var. subincisa (Greene) Steyermark, commonly known as creeping gumweed, is a species of flowering plants belonging to the family Asteraceae. It is native to the southwestern United States and northwestern Mexico, where it grows in dry, often rocky, habitats at elevations of up to 2,500 meters.
Common Names
Grindelia decumbens Greene var. subincisa (Greene) Steyermark has a variety of common names, such as Creeping Gumweed, Creeping Grindelia, Dwarf Gumweed, Prostrate Gumweed, and Smallflower Gumweed.
Uses
Grindelia decumbens Greene var. subincisa (Greene) Steyermark is known for its medicinal properties and has been traditionally used by native Americans to treat respiratory ailments such as asthma and bronchitis. The plant contains a resinous gum that is used in various herbal remedies and medicines to alleviate coughing and congestion. The gum is also used as an expectorant and as a treatment for skin conditions such as eczema. Additionally, the plant is used in the cosmetic industry for its skin conditioning and moisturizing properties.
General Appearance
The Grindelia decumbens Greene var. subincisa (Greene) Steyermark plant's stems are 5-20 cm long and are spreading or ascending with hairy or smooth surfaces. The leaves are alternate and spathulate with irregularly incised margins and are also hairy. The flowers are yellow and daisy-like, appearing in clusters at the ends of the branches. The fruits are small, dry, and have pappus bristles to aid in wind dispersal. This plant has a low-growing, creeping habit, and can form mats across the ground.
Light Requirements
Grindelia decumbens Greene var. subincisa (Greene) Steyermark prefers full sun exposure. It can tolerate some shade but may not grow as vigorously. In shaded areas, the plant may become taller and spindlier, producing fewer flowers.
Temperature Requirements
The plant is native to regions with hot summers and cold winters. It can tolerate a wide range of temperatures, but optimal growth occurs between 60 to 90°F (15 to 32°C). The plant can withstand temperatures as low as -10°F (-23°C) when dormant.
Soil Requirements
The plant can grow in a variety of soil types, including sandy, loamy, and clay soils. It prefers well-draining soils with a pH range of 5.0 to 8.0. The plant can tolerate drought and poor soil conditions but grows best with moderate watering and soil fertility.
Cultivation Methods
Grindelia decumbens Greene var. subincisa (Greene) Steyermark can be grown from seed or cuttings. The best time to sow is in spring or fall when the soil is warm. The seeds should be sown 4-6 mm deep and about 30 cm apart. The soil should be well-drained and rich in organic matter. The plants prefer full sun to partial shade. They can grow up to 60 cm tall and 90 cm wide.
Watering Needs
The plant prefers moderate watering during the growing season. It should be watered once a week or when the soil feels dry to the touch. Overwatering should be avoided as it can lead to root rot. During the winter season, the watering should be reduced to once a month as the plants are dormant.
Fertilization
The plant does not require frequent fertilization. A slow-release fertilizer can be applied during the growing season. The fertilizer should be applied according to the manufacturer's instructions. Overfertilization should be avoided as it can damage the plant.
Pruning
Grindelia decumbens Greene var. subincisa (Greene) Steyermark requires minimal pruning. Dead or damaged leaves can be removed throughout the year. The plant can be cut back after flowering to promote bushier growth and to prevent the plant from becoming too leggy. The pruning should be done with clean, sharp tools to avoid damaging the plant.
Propagation of Grindelia decumbens Greene var. subincisa (Greene) Steyermark
Grindelia decumbens Greene var. subincisa (Greene) Steyermark is commonly known as the Great Basin gumplant. Its propagation is done through both seeds and plant division.
Propagation by Seeds
Propagation by seeds is the most common method for Grindelia decumbens. The seeds can be obtained from mature flowers and should be planted in well-draining soil in the spring. It is important to keep the soil moist but not wet for optimal germination. The seeds will take approximately 2-3 weeks to germinate.
Propagation by Plant Division
Propagation by plant division can be done in the early spring or fall. The plant should be carefully dug up and divided into smaller sections. Each section should have roots attached. The newly divided plants should be planted in well-draining soil and watered regularly until they are established.
It is important to note that Grindelia decumbens can be susceptible to root rot, so it is essential to plant it in well-draining soil and avoid overwatering. The plant prefers full sun to partial shade and is drought-tolerant once established.
Disease Management for Grindelia decumbens Greene var. subincisa (Greene) Steyermark
Grindelia decumbens Greene var. subincisa (Greene) Steyermark is susceptible to a few diseases that can cause damage to the plant. Some of the common diseases that affect the plant include:
- Powdery Mildew: This fungal disease appears as a powdery white coating on the leaves, stems, and flowers, and can cause distortion and stunting of the plant. To manage powdery mildew, remove any infected plant parts, avoid overhead irrigation, and apply fungicides.
- Root Rot: This disease is caused by waterlogged soil and can cause wilting, yellowing, and eventual death of the plant. To manage root rot, improve soil drainage, avoid overwatering, and apply fungicides.
- Tar Spot: This fungal disease appears as black spots on the leaves and can cause defoliation. To manage tar spot, remove any infected plant parts and apply fungicides.
Pest Management for Grindelia decumbens Greene var. subincisa (Greene) Steyermark
In addition to diseases, Grindelia decumbens Greene var. subincisa (Greene) Steyermark is also susceptible to a few pests that can cause damage to the plant. Some of the common pests that affect the plant include:
- Aphids: These small insects feed on the sap of the plant, causing wilting and yellowing of the leaves. To manage aphids, remove them by hand, or apply insecticidal soap or neem oil.
- Spider Mites: These tiny pests spin webs on the leaves and suck the sap of the plant, causing mottled or yellow leaves. To manage spider mites, remove any infected plant parts, avoid overhead irrigation, and apply insecticidal soap or neem oil.
- Caterpillars: These insect larvae can defoliate the plant, causing significant damage. To manage caterpillars, remove them by hand, or apply Bacillus thuringiensis (Bt) or insecticide.
Proper monitoring of the plants, timely management and implementation active management protocols can effectively help to manage these diseases and pests in Grindelia decumbens Greene var. subincisa (Greene) Steyermark, leading to healthy and beautiful plants for years to come.
