Weed Du Jour – Dandelion

If there is one weed that deserves to be called ubiquitous, it’s the dandelion (Taraxacum officinale). This weed can be found everywhere. It’s in lawns; it grows in fields; you can find it in urban areas. If there’s even a small crack in a black-topped driveway, it’s a safe bet that sooner or later a dandelion will grow in that crack!

Dandelion

The dandelion is one of the few weeds that most people recognize. The bright yellow flowers in the spring and fall and the globe-shaped grey seed heads make them hard to ignore.

Dandelion leaves grow in what is called a basal rosette. What this means is that the leaves of the dandelion plant grow in a circular cluster at ground level. The internodes of the plant (the portion of stem between each leaf) are very small and this results in a short plant with leaves that appear to radiate from one spot. The individual leaves are also distinctive. They’re oblong with very deeply cut margins. This gives the leaf a tooth-like appearance and usually the “teeth” point back to the base of the rosette.

In researching this plant, I found some interesting things about the dandelion.

This plant can produce seeds without pollination (a process called apomixis). While the flowers of the dandelion often attract bees for pollination, it’s not necessary. No wonder the dandelion is everywhere – because of apomixis, it’ll always produce seeds.

Dandelion Flowers and Seedhead

The distinctive white seedhead of the dandelion is made up of many mature seeds, and attached to each is an 8-10mm stalk with a feathery umbrella on it called a pappus. These pappi allow the seeds to be scattered by the wind for miles. Every child who has ever picked a dandelion seedhead and blown on it to watch the seeds and their pappi float in the breeze has helped to spread this weed! One more reason why dandelions are everywhere.

Dandelions are also difficult to kill without chemicals. Each plant has a thick taproot that can grow to over 3′ in length. If you snap off the top of the plant, new shoots will develop from the taproot. If you till the ground, pieces of the taproot can grow into new dandelion plants. For years gardeners have used weed knives to dig out dandelions and as much of their tap root as possible. This can work but if  you have a lot of dandelions in your yard, digging them out one by one will take a long time.

Any broadleaf herbicide like 2,4-D (2,4-dichlorophenoxyacetic acid) will control dandelions in turf. Regular tilling will prevent them from getting established in a garden. But know one thing for sure: even if you remove all of the dandelions from your yard, you’ll never win the battle with this weed. More will come thanks to its wind blown seed dispersion.

No wonder the dandelion is ubiquitous!

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