Thanks for the responses. To Kimmsr: I may have been unclear as to the drainage time. None of the holes that I dug were drained after 60 miinutes. The test involves filling the holes twice, and I guess the second time is more important (as the first filling of the soil eliminates to bias from the surrounding soil being dry and gives a "truer" indication of drainage). On the first filling, some of the holes were down to an inch of water after about 60 minutes, but that last inch wasn't really budging, so I just did a second fill at that time and waited another hour, at which point the holes all had MORE than an inch of water in them after 60 min. (but were less than half full). The County guide-book I'm using basically says if it's taking over 60 minutes to drain, you have a problem and need to look into augering or tilling, so I did not keep timing to see how long over 60 min. the holes took to drain. Since I'm taking this info from my LA County planting guide-book, I am reluctant to second-guess or ignore it. Hmmm...maybe the rate of perculation varies by area and is "naturally" supposed to be faster in my area, and that is needed for the Guide's recommended plant list, which is why they want 12" per hour or less for drainage? (I'm guessing.) I would also note that the water seemed to go down reasonably quickly at first, but then slowed considerably as the water got below the halfway point in the holes, which I gess means there's reasonable side-ways drainage from the 6" mark and up, and it is below that that the walls and floor of the hole were more like a bowl than a strainer (or more like a brick than sponge). Basically, for all I, it would take over 3 hours or over 6 hours, or who knows, to wait till the holes were totally empty, so I'm not really sure how bad my drainage problem is. To Ken_Adrian: You suggest getting my County Extension's "guide," but I'm pretty sure that's what I'm using, and what I linked to above. Did you look at that guide, and is it NOT the same thing? Note, with budget cuts and a big city and stuff, it's nearly impossible to get a County person on the phone in Los Angeles, at least when I've called to talk about other stuff, like permits and tree trimming and stuff, so I'm not real confident in my ability to find some one in the County to pick their brain my questions... to Toxcrusadr: Thanks for that reply, I learned some stuff. It sounds like I can till and then use lasagna method without fear of grass sprouting everywhere. If we did til, then add the lasagna layers, we'd then be walking over the soil to some extent to do our planting (cutting through all the layers and planting in the "real" soil that the grass is in, as I understand it), so I am a bit concerned this would cause compaction at least in some areas, and even if we till the soil when it's not wet, the lasagna method calls for wetting down the various layers as you add them, so I'm still not sure if this approach would lead to compaction problem. Maybe my biggest concern, though, is that the tiller I saw for rent at Home Depot looks like it'll only go maybe 6-8 inches deep, whereas the 1-man power auger they rent will go 16 inches deep, maybe more. If I've got a compaction problem below the 8 inch depth, I am wondering if tilling will help that issue at all? Lastly, there's a suggestion that the lasagna method, standing alone, should fix a drainage / compaction problem organically, as the right mixture of ingredients in the soil will lead to thriving organism or micro-organism or whatever, that naturally keep drainage good. (Sort of like imagining if you cultivate worms in your yard, and they will dig holes as they move through the earth creating a healthy amount of porousness and drainage for the soil, but on a bigger level since I'm sure the healthy soil has a lot of living stuff going on apart from worms.) If my image/analogy is correct, and the lasagna method -- done right -- will ultimately fix the drainage issue, do I really need to do anything? It would be nice if the answer is "no," EXCEPT for the fact that the County Guide I'm following SAYS to do augering or tilling before Lasagna if the drainage is slower than 60 min for a 12 inch hole. My main concern with doing the lasagna method without improving drainage is that, if water does not drain fast enough from the lasagna layers, will that sabotage the whole lasagna process? Ken

I completely agree that it is a lot easier to select plants that will tolerate the conditions than it is to change the conditions on the hillside. However, some cut banks have newly exposed clay that might not support much vegetation for a number of years while natural processes slowly change a clay subsoil into a clay soil that can support plants. If this is the case, then you might need to do something to the soil to make planting wildflowers - even wildflowers adapted to clay - feasible. I would consider planting a cover crop. This would be a fast growing ANNUAL crop that will create lots of organic matter, break up the soil with its roots, then die. Oats are popular for this. Annual rye grass is too, but make sure you plant only annual rye, not perennial rye. You might need to break up or at least scratch the surface of the soil before you sow the seeds. I would plant the oats really thickly. For color you could add a few sunflowers to the oats - just use sunflower seed sold for feeding wild birds. Don't plant any perennial plants. If you ask around, you'll get lots of recommendations for perennial plants to cover slopes, and some of these would probably grow, but they would keep growing ifor years and prevent you from eventually planting wildlfowers. If the oats grow well this summer, next spring you can plant wildflower seeds into the dead oats. I'd select species that are native, tolerate clay, and you like. I would not plant any "wildflower" seed mix. Most of the seeds in mixes are not native, and many won't be well adapted for your hill. I think picking out species is the best part of the process and will entertain you over the winter. There are lots of websites that describe wildflowers and how to grow them. I usually try to compare several websites or books decribing each plant to make sure I know a little about each plant before I try to grow it. You can expect despite careful planning that some of the plants you select will thrive, while others won't grow well, This can't be avoided. Eventually you'll know what grows well and looks good on your hillside, but it will take a few years. If there are similar slopes in the area, check out what grows on them this summer for ideas. Expect that most of the plants along a road or behind a building will be non-n ative weeds you wouldn't want to plant, but a few will be natives.

I am confused by what you said about the water running beside your house. From the two pictures it looks like the slope goes from (Picture wise) from left to right, but also falls away from the house toward the street (Foreground). If this is the case, the creation of a swale to direct the water further out into the yard on the left side would take care of much of the problem. While I can not see the left side of the house you may need a little work to divert the water to the front of the house. While there does not look like much of a slope on the right side of the house with the swale and what slope there is could resolve this area. To me the biggest problem with the front yard is the sidewalk? that come out towards the street. That could be rebuilt or removed without much work. As for what appears as unlevelness, that would be best determined when you are on the mower. To me it looks like most of he problems could be resolved with a mattock, knocking down the few high spots (https://en.wikipedia.org/wiki/Mattock) We live about 20 miles east of Raleigh, and have been experiencing 100 degree days with very little rain, but extremely high humidity. So, my recommendation would be you do nothing until some time in October. Then spending a couple days in the yard. On the first day cut and reshape the right side of the yard. Use the resulting dirt to fill in the area of the sidewalk. Next day walk around the yard knocking down the high spots with the mattock. The above is exactly what I have done in my yard and it resolved my problem. The swale does not have to be deep, a 6 to 8" depression in the 3 to 4' wide and about 5 to 7 ' long. If you use what you remove to create a berm on the edge of the swale, it does not have to be dug out that deep. If there is good grass in the area first remove the grass dig down to the depth you want and replace the grass. It has to be wide enough that it does not create a problem for your current or future mowers

First? why is it poorly drained. Does it need surfaced drained or is it from hard pan causing the problem. Rye and tillage radishes will help breakup hardpan. Does it need to boost up the OM to help improve the drainage. does it need some deep tillage to breakup the soil? I have used a subsoiler running about 15" deep to breakup hardpan or in a small area double digging might help. In my zone rye and tillage radishes would need to be planted around labor Day. Don't know if it is too late in your climate