Photo Credit: Bruce Newhouse.
Photo Credit: Bruce Newhouse
Also known as: Slender false brome, wood false brome
False brome is spreading throughout the Willamette Valley at an alarming rate. Originally introduced to the region as an experimental forage plant in the late 1930s, it grows in a variety of habitats and outcompetes native plants in forest understories and oak woodlandsOak Woodlands A mix of oak trees and shrubs..
For a more detailed description, download the False Brome Best Management Practices factsheet.
|Perennial (life cycle lasts more than one year)
|Early Detection and Rapid Response species:
|Grass blades grow up to 1 foot (0.3 meters) tall and flowering stems can reach 4 feet (1.2 meters).
|The leaf blade is wide, flat, and distinctively bright green. When held up to the sky, a fringe of fine hairs can be seen along the edges of each leaf.
Leaves remain bright green throughout the winter when other grasses are dormant.
|Fruit & Flower Description:
|Miniature, white flowers grow on dropping clusters. They are directly attached to the to the plant stem with no stalks.
Only plants in their second year or older produce seeds.
|May to July
How it spreads:
- False brome is a prolific seeder. Each plant produces several hundred seeds annually.
- Boots, clothing, animals, tires, and equipment pick up seeds and spread them to new locations.
- Actively logged areas where false brome is present risk spreading seed on logging equipment.
- False brome can grow in a variety of habitats including shady forests, riparian areasRiparian Areas Areas of land that occur along the edges of rivers, streams, lakes, and other bodies of water., prairies, and roadsides.
- It is a hardy grass species and can tolerate a wide variety of conditions from dry to wet, and sun to shade.
- Without natural constraints, it is rapidly expanding in Oregon.
- It forms thick mats that prevent native plants from establishing. This degrades wildlife habitat and prevents tree regrowth, especially in oak woodland habitats.
- This grass may be fire-resistant, re-sprouting within two weeks of a burn.
- It has low palatability to livestock but can be toxic sheep and goats. Grazing is not recommended.
What we’re doing about it:
- False brome is a priority species for the Tualatin SWCD. As such, our Invasive Species Program has been actively monitoring and treating it throughout the watershed.
- If identified within Washington County, a specially trained crew can come out survey for false brome. If found, the crew will treat the infestation for free.
What you can do about it:
- Please report any false brome infestations to the Oregon Invasives Species Hotline.
- Cultural: False brome’s seeds can easily become attached to footwear or hiking gear. It is extremely important to clean clothing and use a boot brush to prevent spreading seeds to new locations.
- Manual: Small patches can be hand pulled, with the best results in April to early May. Be careful to remove the roots and throw all plant parts away in a tied plastic bag in the trash – not your yard waste bin or home compost.
False brome is similar in appearance to a native brome, Columbia brome (Bromus vulgaris). Columbia brome is an important species in riparian areas as its fibrous roots hold streambank soil and decrease erosion.
It is very difficult to distinguish false brome and Columbia brome, it’s best to consult a weed identification professional when trying to distinguish these species. The best way to tell these species apart is examining their leaves – Columbia brome does not have tiny hairs along the edge of its leaves.