I have a lot of milk thistle (the one with the white variegation) and one or two other kinds that are a little smaller. I don't worry about them until early spring (except in the garden and lawn), and just mow them a couple times in spring when they start to flower but before they set seed. Then at least for my work in thistle fighting I get a considerable amount of compost and mulch for the garden. Fewer of them come up these days than when I first started this, but it's impossible to mow the entire countryside and the wind blown seed tends to get around. I've actually kind of learned to not mind the thistles due to the amount of compost they produce - milk thistle in particular is a great compost crop. Next season I'm putting in some cardoon and artichokes since their cousins seem so happy here. For the lawn I have a manual coring aerator and that's my thistle and dandelion killer. I just go around the lawn and take cores from the center of the rosettes. That leaves cores with the taproot on the surface to die, and the aeration improves the health of the lawn by loosening the soil and improving watcher catching capability and retention, and providing some loose surface soil for overseeded fescue to hide from the birds under and germinate. That can be a lot of cores, but a good job of aeration will take a core ever 6" or so.

you definitely need to burn - work with your NRCS office - they will have contacts on who to work with to get your area burned. what area of WI are you in? you may be able to contact a local pheasants forever habitat specialist to assess your weed control and help you burn your prairie... once it gets established an occaisional burn is the only thing you will need to do - i believe a burn will suffice for the CRP program in lieu of mowing (of course check with NRCS first) ... unfortunately burning isnt going to inhibit goldenrod but it does inhibit other weeds and stimulates the bluestems and other grasses and flowers which will fill in thus making it harder for the weeds to grow. mowing until then helps keep weeds from going to seed ... check out the results the following year after a burn and then look at other options like 24D or roundup selected areas only if the burning is not effective. and yes - its very typical to notice the cyclacle pattern of your weed development... each year a different species is more prevelant than the previous year - very common situation...

Bob, Great Shot, glad to see some of your finches are already molting to their summer breeding plumage, that means spring is coming,,,Hurrah!! Fortunately we got a nice sunny 35degF day today so I was able to get a shot from my bedroom window showing my whole feeder setup. The first shot is looking east from my bedroom window. In this shot you can see my seed hopper and suet feeders on the Maple tree, which is 60ft from my camera position. This location is working very well because many of the birds roost in the Maple tree during the day. Although you can barely see it in the photo about 20ft to the right of the Hopper there is a 65ft high pine tree that affords great cover for the smaller birds. Ten feet to the left of the Maple tree there is a small Butternut tree that is a favorite roosting place for the Morning Doves. I generally see upwards of 35 doves in that tree each morning. Another 15 ft to the left is a second 60ft Pine tree and behind the feeder sight you can see an 18 acres open meadow. You can see the woods are the far side of the meadow. That woods extends for about a square mile and it is mostly old stand hardwoods. Across the road to the left of this photo is another 300 acre hardwood stand, some new growth near the road, but old stand hardwoods from about 100 feet off the road. In the foreground to the left you can see my old garment hanger with the Niger & mixed seed tubes. On the left end on top you can see the plastic bucket lid that I use for a platform feeder. From my vantage point I generally use a 300mm lens to shoot birds on the hopper, suet feeder or on the ground below the hopper, while I use a 200mm to shoot close ups of the birds on the garment rack feeders. As you can see, all the birds at my feeders seem to play nice and I see very little competition.

Sorry for the late response, but if you're still needing to deal with this in the upcoming season (or for new people to this thread), I found a solution that works here in western Washington. 20% acidic vinegar does the trick (https://www.ars.usda.gov/news-events/news/research-news/2002/spray-weeds-with-vinegar/). This is much stronger than household vinegar. I found online: https://www.factorydirectvinegar.com/?gclid=CNWfk4W7g88CFU9qfgodxrYPnw, but if you live in a larger city, you might be able to find it locally. This is caustic stuff, so be careful! Wear gloves and eye protection, do it on a sunny day of about 70 degrees or more, non-windy day, no chance of rain, etc. I do it when I know the neighbor kids are at school - there's no fence dividing our yards. If you cover the whole plant, they say it goes into the root to kill it. One particular thistle I did this to, has had no thistle growth in that spot yet - and it had a good amount of hot weather to come back up again. We'll see what happens this season in that spot. From everything I read, tilling Canada Thistle only makes more thistles - by sprouting new ones from all the broken pieces. And this vinegar doesn't seem to work as well on other weeds. Good luck!