Parthenium alpinum (Nutt.) Torr. & Gray var. tetraneuris (Barneby) Rollins
Parthenium alpinum (Nutt.) Torr. & Gray var. tetraneuris (Barneby) Rollins is a species of flowering plant in the aster family, Asteraceae. It is native to North America and can be found in the western United States. It is commonly known by the names Tetraneuris alpinum Nutt. and Alpine Tetraneuris.
General Appearance
The plant is a low-growing perennial herb that has a caespitose growth habit, which means it forms clumps. It usually grows to a height of 10-25 cm. The leaves are basal and are long, narrow, and grass-like in shape. The stem of the plant is leafless and has one or a few flower heads. The flower heads are showy, radiate, and have yellow ray and disk flowers.
Uses
Parthenium alpinum (Nutt.) Torr. & Gray var. tetraneuris (Barneby) Rollins is a popular ornamental plant used in rock gardens, alpine gardens, and border gardens. Its bright yellow flowers make it an attractive addition to any garden. It is also used as a medicinal herb to treat various ailments such as fever, respiratory infections, and skin rashes.
The plant has also been found to have potential as a biocontrol agent to control invasive weeds. It produces a toxin called parthenin, which inhibits the growth of other plants. Therefore, it has been studied as a possible biological control agent to control invasive plants such as Parthenium hysterophorus.
In addition, the plant has a role in stabilizing soil in rugged areas where it is found growing.
Light Requirements
Parthenium alpinum var. tetraneuris is a plant that is highly adapted to a wide range of light intensities. However, it does prefer full sunlight to be able to grow and thrive. In low light conditions, the plant may grow tall and lanky, and it may not produce as many flowers.
Temperature Requirements
This plant is native to high mountain areas, and it can tolerate cold temperatures. It can withstand temperatures as low as -30 degrees Celsius. However, it may struggle in extremely hot temperatures. Typically, the ideal temperature range for optimal growth is between 10 and 20 degrees Celsius.
Soil Requirements
Parthenium alpinum var. tetraneuris prefers well-draining soils that are slightly acidic. The ideal pH range for the plant is between 6.0 and 7.5. It grows best in rocky or sandy soils that are rich in organic matter. It can also tolerate soils with low fertility levels but may require additional nutrients if grown in poor soil conditions.
Cultivation
Parthenium alpinum var. tetraneuris thrives in well-draining, loamy soils that are nutrient-rich and have a slightly acidic pH. This plant prefers full sun but can also tolerate partial shade in high altitude regions. Planting should be done in early spring, spacing them 6 to 8 inches apart with a depth of 1 to 2 inches.
Watering Needs
Parthenium alpinum var. tetraneuris requires moderate watering, especially when newly planted. Watering should be reduced to keep the soil slightly moist but not waterlogged. Overwatering may lead to root rot, which may stunt growth or cause the plant to die.
Fertilization
Fertilization should be done in early spring before the growing season begins. A slow-release, balanced fertilizer high in nitrogen, phosphorus, and potassium should be used to supplement the nutrient requirements of this plant throughout the growing season.
Pruning
Parthenium alpinum var. tetraneuris requires minimal pruning. Deadheading should be done periodically to encourage continuous blooming during the growing season. Yellowing or damaged foliage should be removed to promote healthy plant growth. Pruning should be done after the blooming period to encourage healthy growth in the next growing season.
Propagation of Parthenium alpinum var. tetraneuris
Parthenium alpinum var. tetraneuris, commonly known as mountain fever, is a hardy perennial plant that can be propagated via several methods including division, seed, and cuttings.
Division
Dividing Parthenium alpinum var. tetraneuris involves separating the plant's roots into several small clumps, each with its own set of healthy roots and foliage. This method is best done during early spring when the plant begins to grow. The soil should be moist, and the plant should be gently lifted out of the ground to avoid damaging its root system. The clumps should then be carefully separated and transplanted into new locations or containers with fresh, well-draining soil.
Seed
Parthenium alpinum var. tetraneuris can also be propagated via seed. The seeds should be collected from healthy plants during late summer or early fall. The seeds should be sown in a well-draining soil mixture and kept moist until they germinate. They should be kept in a warm, bright location until they establish a strong root system and begin to grow. Once established, the seedlings can be transplanted to their permanent location.
Cuttings
Parthenium alpinum var. tetraneuris can also be propagated using stem cuttings. Cuttings should be taken from healthy, mature plants and planted in a moist soil mixture. The cuttings should be kept in a humid, warm location until they have successfully rooted. Once rooted, the plants should be transplanted to their permanent location with fresh soil and kept moist until they become established.
Disease and Pest Management for Parthenium alpinum var. tetraneuris
Parthenium alpinum var. tetraneuris is a hardy plant that grows well in dry and arid regions. However, like all plants, it is susceptible to certain pests and diseases that can hamper its growth and reduce its yield. Here are some common pests and diseases that affect Parthenium alpinum var. tetraneuris and ways to manage them:
Common Diseases
1. Powdery Mildew: This fungal disease is characterized by a white, powdery coating on the leaves. It can weaken the plant and reduce its yield. To manage powdery mildew, you can spray the plants with a solution made from one tablespoon of baking soda, one tablespoon of cooking oil, and one gallon of water. Repeat the treatment every seven to ten days until the disease is under control.
2. Root Rot: This is a fungal disease that affects the roots of plants and can cause wilting and death. Root rot can occur when the soil is too wet or poorly drained. To manage root rot, make sure that the soil is well-drained and not too wet. You can also treat the plants with a fungicide that is effective against root rot.
Common Pests
1. Aphids: These small insects can damage the leaves of Parthenium alpinum var. tetraneuris, causing them to curl and turn yellow. To manage aphids, you can spray the plants with a solution made from water and dish soap. You can also introduce beneficial insects like ladybugs and lacewings that feed on aphids.
2. Spider Mites: These tiny pests can cause yellowing and browning of the leaves, especially in dry conditions. You can manage spider mites by spraying the plants with water or using a miticide that is effective against these pests.
In conclusion, taking care of Parthenium alpinum var. tetraneuris requires proper management of pests and diseases. By following the above tips, you can keep your plants healthy, thriving, and productive.
