I have several patches of these weeds in my lawn. They don't grow very tall, but they spread slowly. They're short enough that I don't think my lawnmower even touches these all summer. In the fall, they turn a burnt color, which is what they are now. It doesn't seem like they turn back green in the spring, but new growth comes up around the "dead" ones. The patches feel almost mossy, but individually, they're very needle-like. It has a hornwort or horsetail type of look, but they're something different. What in the heck is this? And does anyone know a good way to eradicate them?

Scleranthus annuus/German Moss?

That doesn't seem quite right.
This weed does not flower, nor do the stems/roots connect. They do not grow in clumps in that way. Each weed has its own root.

Anybody else have any ideas?

If no one else can identify, you might want to try this:

https://hort.uwex.edu/contact/

It looks very familiar, maybe some sort of juniper seedling?

Maybe something in the Lycopodiaceae family. They do not flower but multiply by producing spores.

Isn't it just a moss, similar to this?
http://store.mossacres.com/hai...

@dean_of_admissions,

It looks like some type of sedge. Is there an agricultural extension office near you or that you can upload a photo to an agent? That's usually what I do if I can't identify it. Or, did you try the U. of Wisconsin's weed identifier web site? Here it is:

http://weedid.wisc.edu/weedid....

I'd love to know what it is. Thanks.

Gayle

https://www4.uwsp.edu/biology/...

https://www.google.com/search?...

These haircap mosses are very attractive.... I certainly wouldn't refer to them as "weeds".

crawgarden said:If no one else can identify, you might want to try the uw-ex program

I just reached out to the UW Extension to see what they thought. If they reply I'll let you know.

Leftward said:Isn't it just a moss, similar to hair cap moss?

stone said:These haircap mosses are very attractive.... I certainly wouldn't refer to them as "weeds".

The hair cap moss seems ridiculously close. In fact, that might the answer. I referred to them as weeds because they have just sprouted up in random patches on my lawn. I haven't found that plant anywhere else on my property. I did say that the entire patches feel mossy. Does my description of them match up with what you know about hair cap moss?
"They're short enough that I don't think my lawnmower even touches these all summer. In the fall, they turn a burnt color, which is what they are now. It doesn't seem like they turn back green in the spring, but new growth comes up around the 'dead' ones."

Detailed information and photos for comparison:
http://www.illinoiswildflowers...

Haircap moss definitely seems like it's in the right alley. But it could be a sort of variation. I still haven't heard from the UW-Extension office.

The best way to eradicate is to lime your lawn.

islander said:The best way to eradicate is to lime your lawn.

Are you saying that this moss thrives in lower pH? And making soil less acidic and more alkaline will help eradicate it?

Mosses are encouraged by lower pH and discouraged by higher pH. It would be ineffective to apply lime (that is alkaline) to an already alkaline soil. In such a case, there would be other factors involved that would need to be addressed. Fortunately, native soils in northern Wisconsin are almost always acidic, and raising the pH (with lime) is likely the best single method to eradicated moss.

I don't know about the southern lawn grasses, but the lawn grasses in the northern half of the US are quite pH tolerant. When you lime a lawn, you are changing the natural environment to encourage certain flora and fauna, and discourage other flora and fauna. Applying lime to an acidic soil will have a greater effect than applying it to an already alkaline soil. The whole idea is to create an environment that supports a desired lawn more than it encourages the moss.

Other things (besides low pH) that encourage mosses are: shade, compacted soil, poorly draining soil (wet or dry) and poor fertility. These are all conditions antithetical to optimal grass growth. Anything you can do to alleviate these characteristics in your lawn will help your grass naturally "fight off" mosses.

Realize this is not necessarily a cure-all concept. Remember I said you are changing the natural environment to encourage certain flora and fauna, and discourage other flora and fauna. You could find that new "weeds" become problematic because they like and compete in the new environment that you create, better than before.

N.B. It doesn't matter what kind of hair cap moss you have. The general identity is good enough in this case, and recommendations would not change.

Mosses tend to be quite delicate, only growing in areas completely unsuited to growing anything else.

Entirely too much effort is wasted fighting moss, when moss is actually the solution, rather than the problem.

People kill the moss, and end up with scorched earth....

If grass wanted to grow in those compacted yards, the moss wouldn't stand a chance.

Seriously.... Enjoy the moss.... If you could figure out how to get rid of the turf... You could leave the mower in the shed!

Definitely moss. It amazes me how much effort people put into producing what is most often a totally unnaturally looking "perfect" lawn. Let the moss thrive!