If and when to remove dead, pulled weeds

Question: While my question may sound odd -- if and when to remove weeds -- it is a question because we are trying to provide habitat for insects and critters. Our reward has been a good "crop" of fireflies. But we are inundated with Japanese Stiltgrass so removing it has been important. I have pulled much by hand and left it scattered over the bare patches it's removal created so that 1) if it has provided habitat t beneficials I have not completely destroyed it and 2) leaving the dead grass is shading these patches so they don't become hideously dried out. So the question is, should I leave these dead grasses lying about (see photos with piles of dead grass, most of it about 12" tall) until the late summer or fall? Or should I remove them earlier/later to be sure to get the grass seeds out? And when I do remove it, do I put it into trash bags for the garbage, or do something else. 

You may see from my pictures that we have a lot of property so we have lots and lots of this *&^%$ grass. 

Thank you for any advice you can give.

responder: An Ask Extension Expert Replied June 24, 2024, 10:34 AM EDT
response: Hi, Whether or not it is usable as an in-place mulch depends on when you have pulled or cut it. If it already has seeds in it, then you won't be doing your land clearing any favors. If you pull it up prior to seed set (which happens in mid-Sept-Oct in Maryland ), it  could be a mulch. However, the leaves are going to fall off quickly and it will just be stems. Effective dense mulches are generally 3" or more deep to prevent germination of seeds and stilt grass doesn't need a lot of light to germinate starting early spring.  You might consider a denser mulch too.  Keep in mind that where the stilt grass has established a presence, there's going to be a seed bank with viability of minimally 3 years to 5 years and beyond before it is exhausted by efforts to continually head back a new sprouts. So, probably 7 years to rid yourself of it by "strimming" or pulling  while in in the vegetative phase.  Also be aware that soil chemistry can change in the presence of stilt grass  from normal acidity expected to more in the direction of neutral and that can impact the native plants you desire to replace it with. You'll want to soil test.  An aggressive native ground cover that competes with the stilt grass and is OK with your growing conditions may be the way to go.  https://extension.umd.edu/resource/japanese-stiltgrass-home-landscapes/ https://extension.wvu.edu/lawn-gardening-pests/weeds/japanese-stiltgrass

responder: The Question Asker Replied June 24, 2024, 11:12 AM EDT
response: Thank you for the reply.   I pulled these stiltgrasses in the last 2 weeks, so early-mid June. I will continue to do so. Presumably I did this before the seeds set so I am not leaving new seeds in that space (If I understand you correctly). I don't plan to use these leaves and stems as permanent mulch, just leaving them there until I find something else to do with them (garbage?).   Can you recommend a native ground cover that might mitigate the stiltgrass? We have shade/part shade for the most part. Some sedges (clump-forming) are doing well but because they form clumps they don't really help much. We also have a range of mature trees: cottonwood, black walnut, red maple, willow oak, and river birch are the main ones.  Again, thank you for the help.    On Mon, Jun 24, 2024 at 10:34 AM Ask Extension <<personal data hidden>> wrote:

responder: An Ask Extension Expert Replied June 24, 2024, 12:15 PM EDT
response: If you have deer, then Packera aurea, called Golden Ragwort may be a good choice. It will rapidly fill spaces with there is part sun to shade.    It's generally the rapid seeders or rhizomatous types that can take up territory from the stilt grass or outrun deer predation. If you just want natives filling in rather fast (*some could be so fast as to require maintenance/removal work) then you could do that. Of the other native choices that also have a more aggressive filler tendency: hay scented fern*, white wood aster*, potentilla candensis, salvia lyrata.   For medium rates or slower, here's a listing of general deer resistant plants sun or shade.  https://extension.umd.edu/resource/deer-resistant-native-plants/