Noxious Weeds That Harm Washington State

garlic mustardAlliaria petiolataDescription: Garlic mustard is a biennial plantthat has a distinctive garlic odor when crushed.During the first year, the plant forms a basalrosette of kidney-shaped leaves. The second year,the stem grows up to 3 feet tall, and the leavesare heart-shaped or triangular and coarselytoothed. Bloom time is early spring, and theflowers are white with four petals.Impact: This aggressive, shade-tolerant plantcan completely dominate forest floors anddisplace native species. It releases compoundsinto the soil that prevent other plants fromgrowing. Fruits can eject the tiny black seedsover ten feet, and the seeds are also dispersed byanimals, boots, equipment, and mulch.Control: Contact your county noxious weedcontrol board if you think you have seen thisplant. Pull up plants - including the roots - beforethey finish flowering and discard them in thetrash. Selective herbicides can be effective forlarge populations. Check boots, clothing, andequipment before leaving a garlic mustard site.W-28