Toxic to horses. Be cautious of Hoary alyssum if you have horses on your property, or you have hay crops. Once this plant gets into the hay, it can cause serious harm to the horses that consume it.
About This Species
Hoary alyssum (False hoary madwort, Hoary berteroa) prefers dry, disturbed sites such as roadsides, rail embankments, and rangelands. It is native to Europe. Hoary alyssum spreads quickly through a long season of seed production. Seeds are dispersed by vehicles, equipment, footwear, wildlife, and birds. It can also contaminate hay. Hoary alyssum is designated as a Regional Noxious Weed by the BC Weed Control Act, as well as a Regional Containment/Control species by the BC Provincial Priority Invasive Species List.
How to Identify
Hoary alyssum is upright to 0.7 m tall and is covered in star-shaped hairs.
It has small white flowers with deeply notched petals. Oval seedpods are 5-8 mm long, somewhat flattened, and held close to the stem.
Leaves are greenish grey in color and clasp closely to the stem.
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Hoary alyssum Factsheet
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