I have been in your shoes (and garden) before. Don't hate me but I would love to have more clay in my soil here in AL, it's so sandy and always seems parched. Anyway, years ago I bought a house (in OH) and wanted half the back yard to be a garden. As usual in a housing development, the top soil was gone, the "dirt" was pure clay. I had a professional spray everything on 1 side to kill it, then had a whole dumptruck of mulch delivered, it made a layer about 6" thick. I started planting flowers and a few veggies right away, amending the holes I dug with compost. That first year most things grew well. The next year when I would move the mulch back to dig a hole, there was an amazing difference, and tons of worms had appeared. I'm a firm believer that good drainage can be mostly attributed to worms. The following year, the mulch was mostly decomposed and more was needed, the soil was much more crumbly and dark, sooo much more well-drained. It just takes time, and you've already waited, so I also say go for it! If it were my $50, I would spend it all on compost to amend individual holes or rows. No need to try to mix it in, just backfill your holes with it, or put along your rows. I agree with your use of the manure/straw on top, don't try to mix it in. Naturally, that stuff would be on top of the soil anyway. The worms, microbes, and rain will redistribute these materials in nature's intended ways. I think most types of raw manure have too much something (nitrogen?) to be helpful below the surface. It sounds like you have a rural-type yard where I would imagine you have plenty of room to make a nice BIG compost pile. If you can make enough of your own, that should solve your clay/drainage problem over time. Also wanted to say that since you've got too much moisture, you might do better at least this year with little hills instead of furrows. This fall, put all of your leaves on your beds. When I lived in OH, I would put up to 15" of leaves on beds and they would be gone by spring. Most of the time I didn't have as much leaves as I wanted from my own yard, but so many people gather this valuable resource from their yard and bag it up for you for free, and even set it by the curb for easy pick-up.

Fungi grow in soils where the conditions they like are, somewhat acidic, fairly moist, with a good bit of woody material. The mushrooms we see are the seed stalks produced by fungi when those conditions are good and they will be reproducing. Neither the fungi nor the mushrooms are in any way harmful so there is no need to remove them except, possibly, for appearances sake. If there is a need to remove them be sure to compost them rather then throw them out since they do have nutrients that could be used by other plants. Here is a link that might be useful: About mushrooms

BIOREMEDIATE your soil! Paul Stamets - Bioremediation with Fungi "In 1975, a military jet fuel leaked over 80,000 gallons of kerosene based jet-fuel into a lake in the suburbs of Charleston, SC. Many people tried to manage the oil spill but it was to no avail. It was almost impossible to stop all of the fuel from being soaked up by the very permeable sandy soil and reaching the ground water. Soon all of the ground water became contaminated and had many toxic chemicals in it. The ground water then began to reach all of the residential area and everyone in the surrounding area knew they were faced with a serious environmental hazard. It was almost impossible to remove all of the contaminated soil and ground water so the only other option was to introduce microorganisms and fungi that could consume all of the toxic chemicals and turn them into harmless carbon dioxide. Because of this introduction of the microorganisms it allowed for any further contamination to come to a complete halt. It even helped to remove 75% of the pollutants that harmed the soil and ground water. This introduction of microorganisms and fungi to an ecosystem or specific area is known as Bioremediation. What is Bioremediation? Bioremediation is a process in which indigenous or inoculated micro-organisms (e.g., fungi, bacteria, and other microbes) degrade (metabolize) organic contaminants found in soil and/or ground water, converting them to harmless end products. Nutrients, oxygen, or other amendments may be used to enhance bioremediation and contaminant desorption from subsurface materials. Bioremediation also allows polluted drinking water to become safe enough for humans and animals to drink. It allows for us [humans] to have a safer drinking source and not be too terribly concerned with the toxins that could be potentially be harmful. Bioremediation is usually classified under 2 types of conditions. Those being aerobic and anaerobic..."

Just thought I'd update this in case somebody else comes across it wonders what I did with it... Decided to fill the gutter with mulch instead. Well, actually... I didn't decide that, it decided for me. I left the dirt even with the gutter, and the mulch kept going into the gutter. I kept trying to keep it cleaned out. And then realized how stupid that was. The gutter is mostly blocked on both sides anyway - something I don't have control of. So may as well have mulch there to soak up the water when it comes, and then it'll either dry out over time, or get wicked back up into the yard possibly. Rainwater harvesting the permaculture way?