Hawkweed is the common name for nearly any species of the Hieracium genus, most of which are considered weeds. Hawkweeds are small, hardy perennials that produce yellow, orange and red flowers that are very similar to dandelions. These flowers blossom at various times from the early spring through the early fall. There are a few types of hawkweeds that are cultivated as ornamental plants, but most gardeners consider the vast majority of hawkweeds to be invasive weeds that must be eradicated.
There are over 10,000 different types of hawkweed plants distributed throughout the world. Botanists have discovered that many species of Hieracium are capable of evolving into new subspecies much faster than other types of plants. Some of the most common species of these plants include common hawkweed, meadow hawkweed and devil's paintbrush. Like many troublesome species of Hieracium, devil's paintbrush was introduced to the United States as an ornamental plant where it quickly escaped into the wild and began out-competing native plants.
Hawkweed flowers appear at first glance to be very similar to dandelion flowers. Hawkweed flowers consist of a dense, round flower-head with dozens of individual small florets that are often mistaken to simply be petals. Each of these florets has a blunt tip that terminates with the the small teeth that separate hawkweeds from similar members of the Aster family. Most hawkweed flowers are bright yellow, but there are also hawkweed species that blossom with flowers in rich shades of red and orange.
Gardeners and landscapers consider most hawkweeds to be a troublesome plant, but these weeds play an important role in the environment. Hawkweeds are pollinated by several types of moths, including the lime-speck pug, the Hebrew character and the dot moth. The fruit and seeds of these perennials are an important source of food for animals ranging from the large yellow underwing moth to the common rabbit.
Hawkweeds have traditionally been used in folk medicine to treat a handful of ailments. Many species were formerly used in the production of teas and tonics to treat respiratory illnesses, nausea, and indigestion. Most of these species are no longer recognized as useful by modern herbalists. The mouse ear, however, is one of the few species of these plants that remains popular in alternative medicine. An herbal infusion made from mouse ear by boiling the entire plant is sometimes used as an expectorant to treat chest congestion and other lung conditions.