Looks like Nutsedge...I've not had to deal with it in my yard, but remember a product called Sedgehammer that my dad used to control it. Here is a link that might be useful: Sedgehammer - Halosulfuron-methyl

Compost and mulch are not the same thing although, as you discovered, a thick layer of compost can initially function as mulch. The EPA laws about this are clear and would have to be violated to make mulch from this wood. If you buy finely ground hardwood mulch from a reputable source, it is good for the soil. It should be very dark, almost black. If you need a lot, it's usually cheaper to get a truck to drop a load of it although it's more work for you to get it where it needs to go. Mulch comprised of larger pieces will last longer but the trade is that it takes longer for the decomposition process to be of benefit to the soil. Really large pieces, like bark mulch, can fail to perform the most basic functions which most gardeners expect it to do - suppress weeds, conserve moisture because the larger pieces do not become interlocked in place. This also makes it more likely to wash away in a hard rain. If you want to visually inspect mulch, please do. Although there is a law, we all know people break laws. I bought some mulch at Maxway this spring that was in a bagged called "professional potting soil." It was nothing but shredded wood and I found bits of plastic, painted pieces, straight edges, etc... all through it. An email sent to the Cowart mulch company of Sugar Hill GA got no response. This is a description of the methods used to visually inspect mulch by the university of FL as one aspect of a process to determine if CCA mulches were being sold: The primary purpose of visual inspection of the mulch was to identify if the mulch was: a) colored and, b) to look for evidence that it was made from recycled C&D (construction and demolition) wood. Non-colored mulch would have natural variations in color. When the change in color on a piece of mulch was abrupt or in the case where the color was extremely uniform, then the mulch was identified as artificially colored. Abrupt changes in color occurred when the colorant did not penetrate the crevices of the wood showing distinct areas of the natural wood color in contrast with other areas where the colorant penetrated the mulch. An extremely uniform color is an indication that excessive amounts of colorant were used giving the mulch a "heavily painted" appearance. When in doubt pieces of the mulch were broken open to determine if the color of the outside of the mulch sample was different than the inside, again indicating that the mulch was colored. Evidence that the wood was made from recycled C&D wood was provided by the presence of painted wood, other objects that are associated with recycled wood (e.g. nails, rope, and plastic), and engineered wood (e.g. plywood, particle-board, oriented strand board, and possible excess of smooth surfaces on the wood). Smooth surfaces on the wood chips were documented since engineered wood is characterized by sawn boards which are characterized by a greater proportion of smooth or straight edges. You can read more at...

Thank you for the lead Tiffany - got my answer HERE and 'name that plant'! I assumed it was a weed because of how invasive the roots are, seems it's not. Seems some folks plant this intentionally. I can't past the the thorns all over it. It feels inhospitable to me. My personal preference would be to eradicate it with out chem...I wonder how easy that will be. Thanks so much for solving this mystery, bob_cville.

I have lots of trees that interfere with my lawn; When I try to seed in the fall the leaves smother everything before it gets established and in the spring there are problems with other stuff the trees shed. its a constant battle. I did get some bluegrass sod down that looked really nice 2 years ago but then these seed pods started falling profusely; I can't explain how it destroyed it but it did. This is my last shot (I say that every year) but I'm worn out and haven't the money to keep doing this. Water is hugely expensive here having tripled in cost since I moved here.