Could they be dandelions?

[rita.dagardna]

Hi,

I found these huge plants in weed area of the yard that I’ve never noticed before. They’re about 6 feet tall before they fall over. Could they be dandelions?

 

[Marck]

Not Dandelion (Taraxacum officinale and other species), but some member of the Chicory Tribe (Cicorieae) of the Daisy Family (Asteraceae). The leaves bear a close resemblance to Common Sow-thistle (Sonchus oleraceus) so I would consider that first. However it would be good to see more flower and cypsela (fruit) characters. There are many Chicory relatives.