In regards to the noxious weeds. No native is ever listed a noxious weed...invasive or aggressives as some natives are they still can't be named as noxious. Only those listed noxious in ANY state are those introduced from outside this country. Maybe you could post some pictures of these to see about an ID or take samples into your local extension office where the weed board is usually located also. Our weed board has booklets containing our noxious weeds with pics/descriptions that is free to the public. Also some of them plants could be from your mix that you think are weeds.
My last quarter of school (this past June) I took a Weed Science class as an elective and what a tremedous help that was. Now I know which to fight and which I can go more lightly on punishment LOL!!
My site (960 sft) is small enough to manage with chopping individuals back or hand pulling and each year (now the 3rd) gets easier as it fills in.

Joepye and others more experienced will chime in I'm sure :D

Vera

Cutting it down is not a bad idea - the main reason we cut new prairies is to keep weeds from going to seed. (The weeds will grow - we just need to keep them from reproducing)

You're experience at this point is as expected. The first years visible growth is mainly BES and Praire coneflowers. Very typical.

The other stuff that you planted is probably still there it's just not visible at this time.

I definitely would not smother and start over.

I would cut it again this later this summer - before anything goes to seed.

Many native plants require two or three growing seasons before they bloom. So you are half way there...it does take patience.

I might do a spring burn next season to kill off some early growing weeds - and the natives should be mature enough that a burn would really stimulate them.

If anselm planted in Spring...he may not have gotten full germination due to lack of seed stratification. I definitely would not start over, but I would perhaps re-seed over the Thanksgiving holiday. Or any time up to mid-February would be okay.

In the meantime, do some weed control, as Joepye suggested.

Thanks for all the information and advice. So I've worked a little more on the weed and wildflower identification. I also realized that I planted two different mixtures, not just one as I stated originally. The other mixture had about 40 different plants (see below).

Currently my assessment is that I have identified the following weeds: bull thistle, curly dock, horseweed, chicory, white campion, queen anne's lace, red clover, clotbur, winter cress (early in the spring), and white sweet clover. And I'm pretty confident I've identified the following natives: evening primrose, daisy fleabane, black eyed susan, yellow coneflower, and wild bergamot (although a little doubtful about this one).

I'd be grateful for any identification assistance/confirmation? I put some pictures on the web at http://www.anselm13.com/pictures/v/IDassistance
Thanks for any help with that if you're interested!

So, I've decided I'll mow everything down, but I was wondering when would be the best time this summer (sooner or later)? And is there any recommended height for mowing?

Concerning a spring burn next year, I have a fence next to my patch and a garage within 5 feet, so I suspect that makes it unworkable (aside from verification with my local township regulations)? If burning is not a possibility, I think mowing is acceptable or at least the only other option as I understand it?

Finally should I plant again later in the Fall (e.g. October to early November) or earlier say September?

Thanks again for the help. It's most useful and encouraging.

The other mixture I planted in 2005 is as follows:
Bergamot Lavender hyssop Showy sunflower
Black-eyed Susan Leadplant Silk milkweed (Common)
Blue vervain Lupine Sky-blue aster
Boneset Mountain mint Smooth beardtongue
Brown-eyed Susan New England aster Smooth blue aster
Butterfly milkweed New Jersey tea Sneezeweed
Cardinal flower Ohio goldenrod Stiff goldenrod
Columbine Ox-eye (False sunflower) Sweet black-eyed Susan
Compass plant Pale purple coneflower White prairie clover
Cup plant Prairie blazing star Whorled milkweed
Dense blazing star Prairie dock Wild golden glow
Dotted mint (Horse mint) Purple coneflower
Evening primrose Purple prairie clover Big bluestem
Hoary vervain Red milkweed Indian grass
Ironweed Rosinweed Little bluestem
Joe Pye weed Rough blazing star Prairie dropseed
Large-flowered beardtongue Showy goldenrod Side-oats grama

I would mow it right about now...as high as you can. If I'm wrong, someone will correct me.

If you can weed whack it to about 8" high, that would be great. The idea is to keep the weeds you mentioned from going to seed.

Now that I know how much good stuff you've planted...WoW! I'm not really sure that you need to over seed. The only problem I see is that you planted in Spring, and lots of native plants need freeze/thaw cycles to germinate. However..if they have had or will have subsequent exposure to freeze/thaw...they might have sprouted this year or maybe next spring.

In other words...I'm not really sure what to advise here!

Sounds to me that your problems are due to a combination of inadequate site preparation and poor germination. One herbicide treatment in the spring will not kill off all the perennial weeds on your site -- as you have discovered. And spring sowing (you didn't say how early) probably didn't give most of your seeds enough cold stratification to germinate during the first growing season. Any that germinated in the second spring would have had a lot of competition.

That said, you do have some good stuff -- probably more than you realize. Definitely don't smother what you've got started. I think you should plan to over-seed this fall/winter.

Mow high to prevent undesirables from seeding this year. You might consider a fall burn. Broadcast a native seed mix late in the fall. A burn plus overseeding will give the new seeds the cool stratification they need, and a decent seedbed to get started next year. You will need to continue mowing for weed control next year (and perhaps longer).

In a site this small, don't overlook the option of hand pulling some weeds and placing seedlings or transplants to add new species. I have a couple of smallish patches of weed-rich meadow that also include some desireable plants. To encourage the good plants, after a rain I go out and pull weeds that are crowding desirable plants. I don't try to eliminate all the weeds, instead just try to give the good plants room to grow and try to eliminate any weed that will really become a long-term problem. Weeds in this category include Canada Thistle, Crown Vetch, Spotted Knapweed, Garlic Mustard, and if I had any, definitely Japanese Knotweed. Most other weeds I pull only if they are crowding desireable plants. When I add a new species I generally start the seeds in six packs, then place seedlings. I find a spot that is all or mostly weeds, clear the weeds, and plant a patch of seedlings spaced appropriately for mature plants. Sometimes I mulch around the seedlings. Each year that goes by I get more and larger desirable plants and fewer weeds. This approach to establishing a prairie wouldn't work on a large scale but should be fine for 2500 square feet.

i agree with ladyslipper.

maybe instead of trying to seed that small an area, just plant it up with ur desires.

also, that is a small enough area to mulch, which will ease ur weedy mind.

froggy

Sample 8 is common ragweed, which is native but annoying. Sample 10 looks like Queen Anne's Lace, which is not native.

Be VERY careful with hand-pulling..it can also pull up native seedlings.

mow it low enough to keep annuals from making seed but high enough to not kill baby perrennials. around 6-8 inches is good.
you can burn before spreading more seed but mowin will suffice.
you need a grass matrix if you dont have one now. I like mostly the shorter grasses. like little blue stem/ prairie dropseed/ brome.
keep interseeding. collect, swap, borrow or purchase seed.
now is a good time to get out and collect.

You also have to think about your definition of "weed". You listed several kinds of clover as weeds. Sweet clover and red clover aren't native, but they are bee food and nitrogen fixers. I actually tend to regard them as desirable in a meadow.

I have had good luck with mulch. It keeps the moisture in the soil and thus makes it easier to hand pull non-desirables. Be methodical, work one very small section and wait. If you get to the point that you like what has happened, then work another section.

This time of year will not have very many new 'good' germinations. Most of what you see sprouting in July/August I consider undesirables!

If you planted back in 2005, your planting should be well established by now. If it's not, I would consider burning some or all of it off with roundup. Maybe start with the worst areas first.

Mow it and spray it this fall, and then again in the spring after the annual weeds have germinated. Spay again in mid May, and plant around the first of June if you live in the North.
Lightly rake in the wildflower seeds with a rake, or cover with peat moss so as not to disturb the soil.
If you still have a lot of weeds, mow it several times during the year, especially before the weeds go to seed. Not shorter than 6-8 inches.

Most prairie plants will flower in the second or third year when they are not competing against weeds.

Looks like this thread was resurrected from the dead by edlincoln. I'd like to hear how it turned out though from the OP if he/she is still around.