Species Spotlight: Common Mullein

 

 

A reproduction of a painting
by the Swedish botanist C. A. M. Lindman (1856–1928)



   Common Mullein (Verbascum thapsus) is known by many names including Great Mullein, Woolly Mullein or Velvet Mullein. It is a member of the figwort family and is native to Europe, Northern Africa and temperate Asia. It was introduced to North America early in the 18th century and cultivated for its medicinal properties. By 1818, it had become so widespread that botanist Amos Eaton mistook it for a native plant and by 1876 it had been recorded as far west as California.

Photo: Forest & Kim Starr



 The plant grows in two stages: the first year it produces a dense rosette of long, broad leaves at ground level. In the second year the plant will usually produce a single long stem which can grow as tall as 7 feet. The end of the stem is densely covered with  yellow flowers that can occupy as much as half its length. Common Mullein's most distinctive feature is its soft, hairy leaves, some between 6 to 19 inches long and 5 inches wide. The leaves grow alternately up the stem and become smaller in size as they ascend. In the western parts of the United States, the plant is sometimes referred to as Cowboy Toilet Paper. 



Photo: Forest & Kim Starr



 The flowers are about 1/2 to 1 inch across and have five bright yellow, rounded petals.  Flowering can last up to three months beginning as early as June but more typically in August. Flowers at the bottom of the stem open first and proceed to open upwards a few at a time. The flowers remain open for about a day. Each flower produces a small seed pod that splits in half to disperse numerous tiny, brown seeds. Each seed pod can contain over 700 seeds. After flowering, the plant will usually die drying to a dark brown color though the stem will remain upright through to the spring.



 Common Mullein can grow in a variety of habitats including roadsides, uncultivated fields, banksides and forest clearings. They frequently colonize bare and disturbed areas preferring dry, sandy, gravelly or chalky soils and sunny locations. Seeds will germinate on bare ground at temperatures above 50 degrees Fahrenheit. Though they will sprout in areas where vegetation already exists, the first-year rosette will grow much more rapidly without competition. Seeds can remain able to germinate for several decades, possibly even for over a hundred years.



 Since it does not grow well in cultivated areas, Verbascum thapsus is not considered an agricultural threat. Though in areas that are overgrazed and in the western United States, where vegetation is sparse to begin with, it can crowd out native grasses. It also frequently appears as one of the first plants to grow after forest fires and can interfere with normal ecological succession. Removal by hand is the easiest way to control the Common Mullein. Herbicides are often ineffectual because of the dense hairs on the leaves. These hairs also make it undesirable for grazing animals. Bare areas should be replanted to prevent it from growing back.

Photo: Stan Shebs

  The Common Mullein is used by a variety of insects and animals. Some bees use the hairs on the leaves to help make their nests. The American Goldfinch will eat their seeds. Other birds are known to eat their leaves or flowers and also pick insects from the flower heads. The plant serves as host for pests and beneficial insects alike. Pests include species of thrips, spider mites and the Mullein Moth. While beneficial insects include the minute pirate bug and the mullein plant bug.

 The plant has been used for thousands of years by humans as a remedy for breathing and skin ailments. It has traditionally been used to treat asthma, coughs, bronchitis, burns, bruises, gout, hemorrhoids, and diarrhea. Native Americans quickly adopted the Mullein plant's medicinal uses after in was introduced from Europe. The Appalachians used Mullein to treat colds and croup. The leaves applied topically were said to soften and protect the skin. The oil from the flowers was used to treat earaches.

 Romans used the flowers to make hair dye and the dried flower stems were dipped in wax to be used as torches. Dried leaves were used as tinder and stuffed into shoes for insulation. The plant is also believed to have the power to ward off evil spirits, Ulysses took Mullein on his journey to protect himself from Circe.