Overview of Bromus tectorum L. var. glabratus Spenner
Bromus tectorum L. var. glabratus Spenner is a plant species in the Poaceae family. It is commonly known as smooth brome or downy brome. This plant is native to Eurasia and introduced to North America as a forage crop, but it has since become a noxious invasive species in many states.
Description of Bromus tectorum L. var. glabratus Spenner
Bromus tectorum L. var. glabratus Spenner is a perennial grass that can grow up to 1.5 meters tall. It has a dense and fibrous root system that can extend up to 1.5 meters deep into the soil. The stem is erect and branching, with the leaf blade ranging from 5 to 25 cm in length and 4 to 12 mm in width. One of the distinct features of this plant is that it has an awned lemma.
Uses of Bromus tectorum L. var. glabratus Spenner
Smooth brome is mostly used as a forage crop, but it is also used for hay and erosion control. The plant can be used for grazing and hay production during the early stages of growth when it is still tender. However, mature plants have a lower nutritive value and tend to be unpalatable to livestock.
Smooth brome can also be used as a cover crop, a part of an integrated pest management system, and for reclamation purposes.
Appearance of Bromus tectorum L. var. glabratus Spenner
Smooth brome has a distinct appearance, with a dense and erect growth habit that forms clumps. The leaves are flat and smooth, with a dark green color that gradually fades to yellow or brown in the fall. The panicle, which is the flowering part of the plant, is branched and up to 15 cm in length. Smooth brome flowers from May to July, producing spikelets that bear up to 7 flowers, each with 2 glumes and an awn.
Light Requirements
Bromus tectorum L. var. glabratus Spenner is a plant that requires full sun to grow properly. The more sun exposure it receives, the more robust its growth will be. It does not do well in shaded areas and may have stunted growth or fail to grow at all.
Temperature Requirements
Bromus tectorum L. var. glabratus Spenner is a resilient plant that can grow in a range of temperatures. However, it grows best in areas where the daytime temperatures are around 20-25°C. It is not suitable for extremely cold environments and may not survive frostbite, while prolonged exposure to temperatures above 30°C may prevent its growth.
Soil Requirements
The plant prefers a well-drained soil and can grow in almost any soil type, including sandy, loamy, clayey, or rocky soils. It can also handle drought conditions and is resistant to arid environments. However, it does not do well in environments with high levels of salinity or alkalinity.
Cultivation Methods
Bromus tectorum L. var. glabratus Spenner, also known as smooth brome, is a cool-season grass that is widely cultivated for forage and soil stabilization. It can be grown in a range of soil types, from sandy to clay, but prefers well-drained soils with a slightly acidic to neutral pH. The ideal temperature for smooth brome growth is around 15-25°C (59-77°F), with a minimum of 5°C (41°F) and a maximum of 30°C (86°F). Smooth brome can be propagated by seed or by division of mature plants.Watering Needs
Smooth brome requires regular watering, especially during the establishment phase. The soil should be kept moist but not waterlogged, as excessive moisture can lead to root rot and other diseases. As the plant matures, it becomes more drought-tolerant and requires less water, but it is important to maintain adequate moisture levels for optimal growth and productivity.Fertilization
Smooth brome responds well to fertilization, and a balanced fertilizer can be applied in the spring and fall to promote healthy growth. A soil test can help determine the specific nutrient needs of the plants, but generally, a fertilizer with a ratio of 4-1-2 (nitrogen-phosphorus-potassium) is recommended. Over-fertilization should be avoided, as it can lead to excessive vegetative growth and reduced seed production.Pruning
Smooth brome does not require regular pruning, but it can benefit from occasional mowing to encourage denser growth and to control weeds. Mowing should be done in the spring or early summer, when the plants are actively growing, but not during the flowering period. A mower with sharp blades should be used, and the height of the cut should be adjusted depending on the intended use of the grass. For forage production, the plants can be cut to a height of 10-15 cm (4-6 inches), while for soil stabilization, a higher cut of 20-25 cm (8-10 inches) may be more appropriate.Propagation of Bromus tectorum L. var. glabratus Spenner
Bromus tectorum L. var. glabratus Spenner, commonly known as smooth brome, is a cool-season grass that propagates through various methods, including seeds, rhizomes, and stolons.
Seed propagation
The most common method of propagation for smooth brome is through seeds. The seedheads of smooth brome contain numerous seeds, which can be harvested and sown directly in the field. The best time to sow smooth brome seeds is in the fall, after the first frost, or in early spring. The seeds need to be sown on a well-prepared seedbed with good soil contact for successful germination. Additionally, the seeds should be covered with just enough soil to keep them in place.
Rhizome propagation
Smooth brome can also propagate through rhizomes, which are underground stems that can produce new plants. Rhizomes can be harvested and planted in new locations to propagate the plant. The best time to plant rhizomes is in the fall or early spring, and they should be planted about 2 inches deep in the soil, with about 6 inches of space between each rhizome.
Stolon propagation
Another propagation method for smooth brome is through stolons, which are stems that grow horizontally along the top of the soil and can produce new plants. Stolons can be harvested and planted in new locations to propagate the plant. The best time to plant stolons is in the fall or early spring, and they should be planted on a well-prepared seedbed with good soil contact for successful rooting.
Overall, smooth brome is a relatively easy plant to propagate, with various methods available to growers. However, it is essential to ensure that the propagation method used is appropriate for the specific needs of the grower and the plant's growth habits.
Disease and pest management for Bromus tectorum L. var. glabratus Spenner
Bromus tectorum L. var. glabratus Spenner, commonly known as cheatgrass, is an invasive species that can quickly colonize disturbed habitats, reducing native plant diversity and increasing the risk of wildfires. In addition to these ecological impacts, cheatgrass can also be affected by several diseases and pests, which can reduce its productivity and vigor.
Common diseases
Cheatgrass is susceptible to several fungal pathogens, including:
- Crown rot: caused by the fungus Rhizoctonia solani, this disease can cause significant yield losses in cheatgrass.
- Rust: several rust fungi, including Puccinia graminis and Uromyces striatus, can infect cheatgrass, causing yellowish-orange spots on the leaves and reducing the plant's vigor and productivity.
- Leaf spot: caused by the fungus Bipolaris sorokiniana, this disease can cause small, water-soaked spots on the leaves, which later turn brown and necrotic.
To manage these diseases, it is important to plant resistant varieties of cheatgrass, remove infected plant material, and use fungicides when necessary. Cultural practices such as crop rotation, proper irrigation, and fertilization can also help reduce the incidence and severity of fungal infections.
Common pests
Cheatgrass is also susceptible to several insect pests, including:
- Wireworms: the larvae of click beetles can feed on the roots of cheatgrass, reducing its growth and productivity.
- Aphids: these sap-sucking insects can transmit viruses and deform the leaves of cheatgrass.
- Cheatgrass seed bug: this insect can reduce seed production and quality in cheatgrass.
To manage insect pests, it is important to monitor populations and use insecticides when necessary. Cultural practices such as crop rotation and the use of beneficial insects can also help reduce the incidence and severity of insect infestations.
