What is this ?

Question: It seems to be some kind of invasive moss or ground cover.  It has taken over my entire garden.  Do you know what it is and how I should deal with it ? Thank you

responder: Answered by the Home and Garden Information Center (HGIC), University of Maryland Extension. For timely gardening information and tips, subscribe to our Maryland Grows blog and quarterly newsletter. Follow us on Facebook, Instagram, and YouTube. Replied June 16, 2023, 3:49 PM EDT
response: This is a type of Liverwort, and they are primitive plants (like mosses) that use spores to reproduce and require some level of consistent moisture to thrive. A surprising 80+ species of liverwort have been observed in (or are expected to occur in) Maryland. At nurseries, they are considered a nuisance because dense Liverwort growth atop plant pots can block irrigation water, but in gardens, they are not harmful by themselves and only indicate that soils might be staying wetter than the plants prefer (unless they are growing among water-loving plant species). Do you use an irrigation system in that part of the yard, and if so, how often is it running? If you don't, is it near the bottom of a slope or natural seep where the ground stays moist, or are you watering certain plants often? (Our weather is so far behind on rainfall right now that a wet area due to rain alone is unlikely.) As a comparison, about one soaking a week in our current weather is probably sufficient for most plants.  Also like mosses, because they do not possess roots, they are easy to remove, even if tedious given how widespread they sound. Raking them up should suffice, and letting the soil surface dry out will help keep them from coming back. Unless the plants in that area require staying wet, you can determine when to water by feeling the soil about four to six inches deep and watering only when it's becoming somewhat dry to the touch at that depth. (If you are trying to germinate seeds, then watering would need to be more frequent.)  If you can share photos of the garden where they are running rampant, we may be able to give more specific advice for removal and for discouraging them going forward. If all else fails, as a last resort, some herbicides might kill them (you'd have to check product labels to see if it's listed), but this is still impractical around desirable plants that could be easily injured by spray drift.  Miri

responder: The Question Asker Replied June 19, 2023, 11:28 AM EDT
response: Thank you for the detailed response.  This area is at the back of my house which is partly shaded in one area, but gets afternoon sun.  It is at the back side of the house which is on a bit of a down slope (gradual).  I don’t water this area at all.  Yes I did try to scoop it out of the top layer one year, but it come back and now is all over the entire back garden.  Unfortunately I have just had the garden mulched. It had not been mulched for 3 years and it was still moist I guess.  Now with the mulch I assume it will just retain more moisture and the will thrive.  Ugh.  I hate that it has covered the entire ground.  It is very thick like a dense moss. I have tried herbicide on it but it seems somewhat resistant.Thanks for your response.On Jun 16, 2023, at 3:49 PM, Ask Extension <<personal data hidden>> wrote:

responder: Answered by the Home and Garden Information Center (HGIC), University of Maryland Extension. For timely gardening information and tips, subscribe to our Maryland Grows blog and quarterly newsletter. Follow us on Facebook, Instagram, and YouTube. Replied June 19, 2023, 5:48 PM EDT
response: It's unlikely the liverwort will continue to thrive for long on top of the mulch (mulch does not retain nearly as much moisture as the soil itself), nor would it survive well underneath mulch if it was covered-up by the new application. Given that, you'll probably see it decline on its own in a little while, especially if our weather continues to stay very dry.  Miri

responder: The Question Asker Replied June 20, 2023, 6:44 PM EDT
response: Fingers crossed !  Thank you !On Jun 19, 2023, at 5:48 PM, Ask Extension <<personal data hidden>> wrote: