They say that weeds are plants growing where we don't want them to grow. This can be so true of our first weed the dandelion. But as you will see, dandelions may be weeds of lawns and gardens yet they have many positive uses to perhaps balance out our disdain for them.
The common dandelion, Taraxacum officinale, is a member of the astreraceae family otherwise known as the sunflower family of plants. It has a composite flower made up of many ray flowers that result in the yellow flower head so characteristic of dandelions. The billowy seed head has many seeds that disperse very well by winds like little parachutes. These seeds are produced asexually, and thus do not require pollination. How many of you as a youth did not blow on the puff balls, inadvertently aiding in seed dispersal?
The word, dandelion, comes from the French word, dent-de-lion, which means "lion's tooth." Other names for this weed include: blowball, doon-head-clock, witch's gowen. milk witch, monk's head, puff-ball and many more. It originated in Europe but now has a cosmopolitan distribution.
When dandelions first germinate in the spring, they can be confused with many other plants that have leaves that are arranged in a rosette. These include rush skeleton weed and spotted catsear. After emergence, dandelions will grow a very long and thick taproot. That is why digging up dandelions -- even with a dandelion digger- -- often is futile once they have been growing for a while. While they propagate through seed like an annual, they are in fact a perennial because of this large taproot that readily re-sprouts if too much is left behind.
Chemical control of dandelions, especially in lawns, can involve a pre-emerge herbicide applied in the spring and a post emergence herbicide like 2,4-D once they emerge from beneath the soil. Glysophate can also be used but since this chemical kills all green plants, lawn use is not recommended. There are several potential organic approaches to weed control but these will be covered in a later separate column addressing organic weed control methods.
Now what are the positive attributes of dandelions? Well they provide food for wildlife and are extremely important early season nectar and pollen sources for bees and other pollinators. They are edible in their entirety and have medicinal uses such as treatment for infections and as a diuretic.
I'll leave you with a quote from Ralph Waldo Emerson. "What is a weed? A plant whose virtues have never been discovered." So I guess a dandelion is both a weed and a valuable plant. Go figure!
Jim Leser retired to Cedaredge in 2007 after a career with Texas A&M University Extension in entomology. He is a member of the Cedaredge Tree Board and a Colorado Master Gardener.