absinth wormwood
(Artemisia absinthium L.)

Overview

Appearance

Artemisia absinthium is an herbaceous, perennial plant that can grow up to 5 ft. (1.5 m) tall. It has many branching stems arising from a woody base.

Foliage

Leaves are alternate, gray-green, 1-4 in. (2.5-10.2 cm) long and give off a strong sage-like scent when crushed. Lower leaves are divided into 2-3 segments and the upper leaves are not divided.

Flowers

Flowering occurs in midsummer, when pale yellow, tubular flowers develop in drooping heads in the axils of the leaves.

Fruit

Seeds are small and easily scattered being dispersed mainly by wind, water, and animals. Each stem can produce up to 50,000 seeds.

Ecological Threat

Artemisia absinthium invades open and disturbed sites such as pastures, rangelands, crop land, stream banks, prairies and old fields. The plant is native to Europe and was first introduced into the United States in the mid-1800s.

Resources

• Fire Effects Information System - USDA Forest Service
• Element Stewardship Abstract - The Nature Conservancy

Selected Images

Maps

Invasive Listing Sources

• Colorado Noxious Weeds
• John Randall, The Nature Conservancy, Survey of TNC Preserves, 1995.
• Native Plant Society of Oregon, 2008
• North Dakota Noxious Weeds
• Pacific Northwest Exotic Pest Plant Council, 1998
• South Dakota Noxious Weeds
• Washington Noxious Weeds
• WeedUS - Database of Plants Invading Natural Areas in the United States
• Wisconsin Noxious Weeds
• Wisconsin's Invasive species rule – NR 40

References