LEAFY SPURGE

Leafy  Spurge

Growth Habit: Perennial, erect, up to 3' tall, spreading by seed or creeping roots.

Leaves: Alternate, long, narrow, ¼" wide and 2" long, usually drooping.

Flowers: Inconspicuous, surrounded by large heart shaped floral leaves which turn yellow-green near maturity.

 

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HOUNDSTONGUE — Cynoglossum officinale L.

Boraginaceae — (Borage Family)

A mound of 12 inch, lance shaped, hairy leaves grows the first year. The leaves have a light green central vein which becomes the leaf stem.  The second year growth also includes at least one branching stem.  The stem leaves become smaller nearer to the flowers, more narrow, and clasp the stem.  All plant parts except the flower petals are hairy.

On the upper half of the stem, flower stalks grow just above the leaf at the connections of leaf and stem.  Each flower stalk is crowded with buds, then purple flowers of 5 petals that hang downward.  As the flowers mature each produces 4 prickly nutlet/seeds arranged around the pointed remains of the pistil.  Each plant produces approximately 2000 seeds that attach to animal hair or clothing and are distributed far and near. 

Houndstongue is toxic causing liver damage in livestock.
 
Horses are especially affected with sheep being more resistant.  Animals may survive for six months or longer after they have grazed on an infested area.  This plant depends on long term moisture and becomes a direct threat to wetland areas where it crowds out all native species.

The following is courtesy of Weeds of the West:

Houndstongue is a biennial growing one to four feet tall and reproducing by seed. Leaves are alternate, one to twelve inches long, one to three inches wide, rough, hairy, resembling a hound’s tongue and lacking teeth or lobes. Flowers are reddish-purple and terminal. The fruit is composed of four prickly nutlets each about one-third inch long.

Houndstongue was introduced from Europe. It forms a rosette the first year and sends up a flowering stalk the second year. It may be found in pastures, along roadsides and in disturbed habitats. The nutlets break apart at maturity into bur-like seeds and attach to clothing, fur of pets, and camping gear. Houndstongue is toxic, containing pyrrolizidine alkaloids, causing liver cells to stop reproducing. Animals may survive for six months or longer after they have consumed a lethal amount. Sheep are more resistant to houndstongue poisoning than are cattle or horses. Horses may be especially affected when confined in a small area infested with houndstongue and lacking desirable forage. Therefore, ranges and pastures should be maintained to encourage production of grasses and high quality forage.

Growth Habit: Biennial, spread by seed. Rosette is formed on ground 1st year, flowering stalk elongates 2nd year.

Leaves: Velvety to touch. Basal – broad, lance-shaped. Upper – narrower, pointed, clasping stem.

Stems: Heavy, erect, usually branched above, to 3` tall.

Flowers: Dark red, rarely white, ¼" diameter in terminal clusters.

Roots: Taproot.

Seeds: Fruit consists of 4 flattened bur-like nutlets, each ¼" long with short barbed appendages.

Other: Burs attach to hair and fur of animals and are easily transported.

(Courtesy of Weeds of the West)

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