Overview:
Piptatherum exiguum (Thurb.) Barkworth, comb. nov. ined., also known as the small mountain ricegrass, is a perennial grass species native to North America. It belongs to the Poaceae family and is commonly found in high-altitude prairies, meadows, and open coniferous forests of the western United States and Canada.
General Appearance:
The small mountain ricegrass grows up to 20-60 cm tall and has fine, light green leaves that measure 3-8mm wide. The plant has a shallow rhizomatous root system and produces erect, slender, and wiry stems that end in a spike-like inflorescence. The inflorescence measures 3-10 cm long that bears 1-3 small spikelets. The spikelets contain small, awnless flowers that produce small, longitudinally ribbed fruits, ranging from 3-4mm long.
Common Names:
The plant is commonly known as small mountain ricegrass, small rice grass, or Thurber's rice grass. In some regions, it is also referred to as the delicate alkali grass, tufted hairgrass, or threadleaf ricegrass.
Uses:
Piptatherum exiguum serves as a forage species for livestock, particularly in winter months when other forage plants are limited. It is also a source of food for wildlife such as elk, deer, and small mammals. The plant has shallow roots, which makes it useful for stabilizing soil and preventing soil erosion on steep slopes. Some native American tribes used the plant to treat ailments such as gastrointestinal disorders and skin rashes.
Light Requirements
Piptatherum exiguum typically grows in areas with full sun exposure or partial shade. Too much shade can lead to stunted growth or even death. Therefore, it is recommended to provide adequate sunlight to ensure optimal growth.
Temperature Requirements
Piptatherum exiguum grows commonly in temperate regions with average temperatures ranging from 18°C to 26°C. Extreme cold or heat can be detrimental to the growth of this plant. Therefore, providing a moderate temperature is essential for its growth and survival.
Soil Requirements
The plant prefers well-drained soil with moderate to high fertility. It is recommended to provide a soil mixture of loam or sandy loam. The soil pH level should be neutral to slightly alkaline, ranging from 6.5 to 7.5. As a native grass, Piptatherum exiguum is drought tolerant but not flood tolerant, and overwatering should be avoided.
Cultivation Methods
Piptatherum exiguum, also called the “small false needlegrass,” is a perennial grass that requires well-drained soil and full sun for healthy growth. The plant can be propagated by seeds or division of the root system. Plant the seeds in the fall season about a quarter-inch deep and keep the soil moist until the seeds germinate.
Watering Needs
Piptatherum exiguum prefers to grow in soil that is consistently moist, so regular watering is necessary to maintain healthy growth. It is recommended to water deeply once a week, especially during the dry season. However, the plant does not tolerate standing water, so proper drainage should also be ensured.
Fertilization
Regular fertilization is not necessary for Piptatherum exiguum, as the plant can grow well in poor soil. However, adding some organic matter to the soil, such as compost, can supply the necessary nutrients and improve soil quality. Avoid over-fertilizing, as it may lead to excessive leaf growth that weakens the plant.
Pruning
The small false needlegrass does not require much pruning, but cutting back the wilted or yellowed leaves can promote healthier growth. Pruning can also help control the spread of the plant and keep it in shape. Cut the leaves about an inch above the crown to avoid damaging the new growth. Pruning can be performed in the spring season after the last frost or in the fall season before the first frost.
Propagation of Piptatherum exiguum
Piptatherum exiguum can be propagated by both sexual and asexual methods. The plant is a perennial grass that produces numerous tillers or stems from the base and can self-seed in favorable conditions.
Propagation by Seed
The easiest and most common method of propagation in Piptatherum exiguum is through seed. The seeds of the plant can be sown directly in the ground in early spring or fall, and they will germinate in a few weeks, given the right conditions. The optimal temperature for seed germination is around 20-25°C, and the seeds should be sown in well-prepared, moist soil. The seedlings will need regular watering, and after the first year, they can be transplanted to their final location.
Propagation by Division
Piptatherum exiguum can also be propagated by division. This method involves digging up the entire plant, dividing it into smaller segments, and replanting each segment separately. This technique should be done in the early spring or fall, when the plant is dormant. It is important to choose a healthy plant and to use a sharp, sterile tool to divide the plant to prevent damage or infection. The divided segments should be replanted immediately in a well-prepared soil and watered regularly until the new roots have established.
Disease and Pest Management for Piptatherum exiguum
Piptatherum exiguum is a hardy, drought- and heat-tolerant species that is relatively disease- and pest-resistant. However, like any plant, it is vulnerable to certain problems that can lead to reduced growth and yield. Here are some of the common diseases and pests that might affect Piptatherum exiguum and some ways to manage them:
Common Diseases
Fungal Leaf Blight: Fungal leaf blight is a common disease that causes brown or black lesions on the leaves of Piptatherum exiguum. The disease can spread rapidly and cause defoliation if left untreated. To manage fungal leaf blight, it is important to remove and dispose of infected leaves, improve air circulation around the plant, and avoid watering the foliage in the evening. Fungicides may also be applied to manage the disease.
Root Rot: Root rot is caused by a number of fungal pathogens that can thrive in waterlogged soil. Symptoms of root rot include yellowing of the leaves and wilting of the plant. To manage root rot, it is important to ensure that the soil is well-drained, and to avoid overwatering the plant. Fungicides may also be applied to manage the disease.
Common Pests
Aphids: Aphids are small, sap-sucking insects that can colonize the leaves and stems of Piptatherum exiguum. Symptoms of aphid infestation include yellowing of the leaves, stunted growth, and distorted foliage. To manage aphids, it is important to remove them physically using a strong spray of water or by applying insecticidal soap or neem oil. Natural predators like ladybugs and lacewings can also be encouraged to control aphid populations.
Grasshoppers: Grasshoppers are common pests of Piptatherum exiguum that can cause significant damage by chewing on the leaves and stems of the plant. To manage grasshoppers, it is important to remove weeds and other vegetation that can serve as breeding sites, and to use physical barriers like row covers or netting to protect the plant. Insecticidal sprays may also be applied to manage grasshopper populations.
By managing these common diseases and pests, you can help ensure that Piptatherum exiguum thrives and produces a healthy yield.
