I have this weed that has spread in the back of my garden. It is an area that probably gets sun/shade about half and half. I have sprayed it with round up but even that doesn't seem to kill it. It makes it turn yellow a bit but doesn't kill it. In fact the yellowish color in these photos were taken...maybe a week after round up. It lays flat to the ground and mounds to only about 1/2" tall.

Perhaps a liverwort?

It looks a lot like a lichen to me. They can spread but I don't think they are harmful. They don't typically have deep roots I think so your best bet is to dig it up.

It can be hard to tell the difference between the two (liverwort versus lichen):

https://www.anbg.gov.au/lichen...

Definitely a liverwort. An ancient type of plant related to mosses that thrives in damp shady spots and you often see it growing on the surface of potted plants. They grow in areas of compacted or impoverished soil or poor drainage.

It's quite charming IMO and totally unnecessary to spray it with poisons which as you've found won't kill it.

Thanks. I am going out to the garden to take a closer look at it. I'm tending to think it is the thallose liverwort. I'm going to try the "scratch" test that they mentioned in the article. I'll let you know what I see.

Well the scratch test didn't show any results. Here are some pictures of some that didn't get sprayed. It was growing in a little patch of iris. (I need to get them out into the sun.)

You can see in the 2nd picture that it seems to be growing on top of a leaf that fell last fall.

I'm calling it liverwort. Thanks for the help. Although I do hope to get rid of it.