Hi John, I just saw your latest post. I’m reluctant to speculate further without more botanical clues. You could try the folks on the Laramie Agriculture Extension for further help. Best wishes to John! Laura https://wyoextension.org/laramiecounty/agriculture-horticulture/

This plant was much bigger last year when I tried to get rid of it. In the photo the leaf is about 6 inches long. Previously the leaves were up to 18 inches long. This plant has never produced any flowers. It produces these leave that almost appear to be like a leafy vegetable. This year it has come up in a spot that is about three feet from the spot where it originally showed up. Any ideas? Thanks

Horseradish (Armoracia rusticana). https://commons.wikimedia.org/wiki/File:Armoracia_rusticana_01.JPG

A species of Rumex, curly dock (Rumex crispus). https://en.wikipedia.org/wiki/Rumex_crispus

Link to eradication method for woad. http://ipm.ucanr.edu/PMG/PESTNOTES/pn74175.html

With a few leaves & no flowers, it’s difficult to tell. Do you know what its flowers look like?. I could only speculating for now. Some of the similar looking leaves include, dock (Rumex), horseradish (Armoratica rusticana) and woad (Isatis tinctoria). According to sources, woad’s root can more than 5ft in length. Flowers are needed to confirm or rule out those mentioned above. Check out these included links for more information & eradication method for woad. Best wishes! Image of a young woad seedling. http://www.naturesrainbow.co.uk/wp-content/uploads/2016/11/Woad-root.jpg