I am guessing here, but it could be that the old Chinese elm stump was not ground out, so the soil layer is too thin to support grass or flowers. We had a Norway maple that was cut down after damage from a wind storm, and the stump was ground down a bit. Even so, the soil is only two or three inches deep in places, and so the grass I have planted there is spotty. However, we often see mushrooms over this spot in the warmer months, after heavy rains. So I know the remains of the tree stump are decomposing underground. Last month I had to add a wheelbarrow load of fresh dirt to the site, because the ground is slowly subsiding as the stump decays. I think that if you water the site of your elm stump periodically, you can accelerate the rate of decay.

You will need to kill out the zoysia or it will likely reappear in spots from any left behind rhizomes. Roundup will do the job, however you need to do it while it is still green. About a week later, remove or till the zoysia into the soil. Apply a starter fertilizer and a blend of turf type fescue (not K-31) at a seeding rate of 15 lbs. per 1000 s.f. and lightly till in shallow (1" max.) or hand rake to slightly cover the seed. Your local nursery or farm center can advise you on TTF varieties and blends for sun/shaded, traffic areas, drought tolerence etc. You may want to post on the "Lawn Forum" as there are some knowledgeable people there.

Most local retail garden centers will have lawn seed blends suitable for a variety of PNW growing conditions. They will be various combinations of fescues and perennial ryegrasses. The fescues tend to be much more shade tolerant than the ryes, so look for a blend that features them. These are often labeled as directly as "shady lawn mix" :-) Ryegrass requires more sun to thrive but tends to hold up better to foot traffic. Fescues also tend to be more drought tolerant than the ryes, another reason blends featuring these seeds thrive in shadier areas under high tree canopies.

I'm not going to try and moderate what is a very active digression from the original issue, but I can try to clarify some of the statements as I understand them. Note: I'm not necessarily contributing to the OP's question, either. I just want the issues to be understandable with as much as we know. yardtractor said, Other than Milo, no organic fertilizer supplies N without a prolonged and unpredictable period of microbial processing. Prolonged and unpredictable...Hence the term, slow release. I prefer delayed release because slow release implies that there is a release beginning when the product is applied. I believe for the grain type organic fertilizers it is more like no release at all for 2 weeks and then a build up to the point where the grass looks much better by the 3 week point. Then as more of the product is decomposed by the microbes, nutrients are delivered to the plant by known biological communication systems as the plant needs it for months down the road. And that is my opinion about both prolonged and unpredictable nature of organic fertilizer. Prolonged, yes. Unpredictable, not really. Now if the temperatures are below 50 degrees, that 3 weeks will be longer, so maybe that is what yardtractor was referring to. But for the grass growing season 3 weeks is a pretty solid prediction for "release" of grain type organics. Using a single cultivar of a plant can be a little more risky in terms of susceptibility to disease or other issues. If you have a blend of KBG cultivars and a disease comes in and wipes out all of one cultivar, then you have the remaining cultivars to fill in for you. That's what they're talking about. yardtractor also said, and I don't mean to sound like I'm picking on you, The reason I cut an exception for Milorganite is that Milo contains 40% fast release urea that does not need weeks of rotting for that to become available. My understanding is that milo is made from stage 2 or class 2 biosolid waste with a dash of iron chloride and iron sulfate. There is no urea in Milorganite - at least not the homeowner variety in the 30-pound bag. That seems to be confirmed by the MSDS for the product. If it has any faster release effect than the grain type organic fertilizers, that speed would be due to the predigestion of the material to bring it up to the class 2 biosolid stage. With reference to the use or possible repeated use of starter fertilizer (high P content), Morpheus mentioned that overuse of heavy P fertilizer products was illegal in several states - or words to that effect. Yardtractor went into retired attorney mode asking for details and eventually I could see him asking for landmark court decisions. Who cares? The problem is we are a homeowner forum with a vast and deep knowledge of lots of information, but we don't know everything. Whether it is legal or not in YOUR state, what we do know is the overuse of P historically has turned even huge bodies of water into slimy green masses of floating goo and fish carcasses. Those of you living on Lake Erie should be plenty familiar with the effect of washing too much P down stream. I believe morpheus is trying to save the OP some hassle, time, and money by keeping to an organic approach that has proved to work. Sure there are chemical approaches that work, but the owner too often ends up worrying about picking the right brand, getting the right NPK, using too much, using too little, thunderstorms washing it away, and forgetting to water it in. With grain based organics you can eliminate those worries. Legality of fertilizer use is such a side issue. If the OP has a soil test showing low P in the soil, morph would be the first to recommend balancing it with starter fertilizer. Without such a soil test, it is not prudent to pile it on.