Dandelions are tall weeds that thrive in moist areas with full sun. The perennial weed does not have stems but instead has leaves that measure ½ to 3 inches wide. The leaves grow in clusters, which form the shape of a lion's tooth, hence, the name of the plant. Dandelions have a strong root system that grows below the soil approximately 5 to 18 inches deep. Once cut, the roots may regenerate slowly at a rate of 1/2 to 2 inches per year.
Dandelion plants reproduce by expelling thousands of seeds into the air, which are then distributed by the wind. The seeds land in meadows, pastures, fields and on lawns. The seedlings usually flower from early spring until the first fall frost.
Since dandelions grow in large clusters and clumps, the plant can overrun residential and commercials lawns, competing with healthy grass for the same space as well as sunlight, water and nutrients. This fight inevitably leads to the demise of the healthy grass. To prevent this, physical and chemical control methods are applied to deter and destroy the noxious weeds.
Turf grass seed
Step 1: Spray dandelions in the late winter or early spring before flowering with herbicides, such as isoxaben and oxyfluorfen.
Step 2: Replace the newly sprayed ground with grass seed, since the herbicide causes open, empty spaces on the lawn. Sow the ground with dense turf grass seed in mid-spring on a warm, sunny, non-windy day. Water the seeds daily and fertilize once a month until the first fall frost. Use a 3-inch layer of organic mulch, such as wood chips or bark, to kill established dandelions and deter new seed growth.
Step 3: Apply herbicide spray in the early summer to ensure all dandelion weeds have been destroyed. If dandelions do appear, use a dandelion knife to dig the entire plant and root system out of the ground. Periodically monitor the grass for potential dandelion growth.
Dandelion roots cause a diuretic effect in the human body when consumed in tea or pill form. Holistic healers recommend using dandelion root to naturally treat kidney disease and high blood pressure problems. Dandelion root also has antioxidant and digestive aid properties that improve the immune system as well as the liver, intestine and gallbladder function. 
Consult your primary care physician first before taking any natural supplements.