When you pull them out, do you get the roots too? Or does the plant break off?

Whatever the answer, never let them set seed.

It bears a resemblance to wild lettuce and also to perennial sowthistle. More like the sowthistle. Pull it if you can, but if it is perennial sowthistle, it has an extensive root system that will put up new sprouts.

You can wet a cotton glove with concentrated glyphosate (the 42% or so active ingredient, diluted 50/50 with water), then gently run the plant through your fingers. This treats the weed without getting any herbicide on your juniper.

Thanks you guys! When I pull it up it's like dandelion roots with little fingers coming out the side of the main shoot.

Thanks for the tip on the gloves! I would never have thought of that. I tried to attack one section of it over the weekend by pulling where I could and then laying cardboard over the juniper and spraying. I'm experimenting between pulling and spraying in different sections so I can see what works best.

Thanks for all the help and tips!

Do NOT use a glove in that manner unless you wear a chemical proof disposable glove under it. And I don't mean the cheap ones you can buy at the grocery store. I surely hope that beeone follows that safety practice.

Chemical resistant nitrile gloves can be found in most gardening or horticultural supply sites. I believe that my husband buys his from Amazon.

Definitely Rhizo! I have gloves that I would use "under" any cloth gloves. In fact I only use nitrile coated gloves to garden in :)