YELLOW TOADFLAX — Linaria vulgaris Mill.

Scrophulariaceae — (Figwort family)

Yellow Toadflax is one of the weedy eye-catchers on the Wyoming noxious list; it is sometimes called “butter and eggs”.

Seedlings resemble miniature spruce trees.  The leaves are slender, long, and drooping, bright green, connected by the central vein to the tall stem. 

An abundance of upright stems, some growing 2ft. tall, not much branched, are supported by woody perennial creeping roots.

Roots are reddish at the soil line becoming white or cream colored below ground. 

The upper 1/3 of the stems are covered by yellow flowers that resemble those of the snapdragon with a one inch pointed beard and a bright orange fuzzy lip.

The flowers produce capsules containing hundreds of flattish oval seeds edged by papery ruffles which carry in the wind like frisbees.  Each plant can produce up to 30,000 seeds.  This plant can prosper in poor soil and dry conditions.

The following is courtesy of Weeds of the West:
Yellow toadflax (commonly known as “butter and eggs”) is perennial, one to two feet tall, reproducing by seed and underground rootstocks. Leaves are pale green, numerous, narrow, pointed at both ends, two and a half or more inches long. Flowers have bright yellow spurs that are one inch long with a bearded, orange throat. Fruit is round, ¼ inch in diameter, brown, two-celled, with many seeds. Seeds are dark brown to black, 1/2 inch in diameter, flattened with a papery circular wing.

Yellow toadflax is a native of Eurasia, introduced to the United States in the mid-1800s as an ornamental. This creeping perennial is an aggressive invader of rangelands, displacing desirable grasses. It is also found along roadsides, waste places and cultivated fields. An extensive root system makes this plant difficult to control. It can also easily be transplanted with other flowers and plants on accident when trading perennial plant materials within a landscape or with friends.

CAUTION: Yellow Toadflax contains a poisonous glucoside that may be harmful to livestock.

Nonstandard name: butter and eggs.

Growth Habit: Perennial, often over 3` tall.

Leaves: Long and narrow, numerous, pale green, smooth and pointed, attached directly to the stem.

Stem: Smooth, erect and sometimes branched.

Flower: Snapdragon type, 1 to 1½" long with spur, bright yellow with deep orange center.

Roots: Woody, vigorous, well branched with many laterals.

Seeds: Round ½" in diameter, dark brown to black with a papery circular wing.
(Courtesy of Weeds of the West)

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