Stewart Robert Hinsley wrote in
:

Yes. Do a google image search for fasciated dandelion and fasciated
specimens of several other species turn up.
--

Hey, the first blog I hit had a really good photo of the type of Dandelion
I've seen -- even had the superwide stem!

http://briande.spaces.live.com/PersonalSpace.aspx?_c01
_blogpart=blogmgmt&_c=blogpart

Here's a good explanation, too:
What causes fasciation? According to Wikipedia:

"Fasciation (also: cresting) can be caused by a mutation in the
meristematic cells, bacterial infection, mite or insect attack, or chemical
or mechanical damage. Some plants may inherit the trait."

The fact that it might be inherited explains why there could be a great
deal of them in one location.

One thing I did note about those wide stems is they often split lengthwise.