All your question are answered in the link below. Do note: Preventative V's curative names and time frames. Here is a link that might be useful: Home Lawn Grub Control Products

I'm interested in this one. It looks to me like watering was the obvious problem. I wish you had mentioned where you live, but if your temps are over 105 from June through Aug, that pretty much narrows it down to a band from Las Vegas south through Indio to Calexico and east to New Mexico. I grew up in temps like that (before the SoCal smog cooled things off). Your problem area is on a slope. Slopes, hills, and mounds drain water fast. With your low humidity, high temp, and on a slope; your grass is not getting enough water. The only way to really keep moisture on that would be with a soaker hose running continuously at a trickle. Rather than do that, I would let the grass die out and do something else. It also looks like you have the wrong grass for your zone. It looks like fescue in the pictures. It should be bermuda if you absolutely have to have a grass. At this point I would plant xeriscape plants on the slope. I don't think you can water it enough under your conditions. If you don't want xeriscape plants, then you could mulch heavily in there and plant pretty much whatever you want that is adapted to your area. Keep the mulch on, though. When people come here and report a "clay" soil, they usually have clay but without a healthy population of microbes, especially fungi. The people with healthy soil don't usually report having clay. The fungi will help your soil retain moisture, but you have to have moisture for the fungi to survive. That's where the mulch comes in. As for the rest of the lawn (not on slopes), you should water deeply and infrequently. In your case, twice a week is probably infrequently but three times is pushing the limit. The idea is for the surface of the soil to dry out between waterings so weed seeds will not germinate. No problem with twice a week in your area. As for duration, 20 minutes is not nearly long enough. I water from 1-3 hours per zone. Last night I watered 6 hours because I've been away for 3 weeks and my wife doesn't water that long. Once you have a healthy population of microbes, your soil will not allow runoff, so even with 6 hours, it all soaked in. As for your yard, unless your sprinkler pours out the water, I would start moving up toward 1 hour (from 20 minutes). Watch your grass for signs of wilting. If it wilts, water immediately but water more heavily (longer) until you can go from one watering to the next without wilting. With a clay base, once you get the microbes going, you might be able to stretch it out to once a week watering, even with your heat. Watering at night is probably not a problem in your area. Our water restrictions in San Antonio require night time watering year round. I've been doing it for a couple years and have not had any more problems than when I watered in the day - and I was expecting problems. Then again I'm on an 100% organic program and fungus diseases are not much of a problem, so your mileage may vary.

antzy - You'll hear a lot here about avoidance of chemicals and not harming beneficial insects and the like. And believe me, all of it is good advice; after all, why kill an insect or worm if it is helping to aerate (and eventually fertilize) your lawn? However, I, for one, have suffered ant infestations that have so over-cultivated beneath the lawn that two areas dried out and died - because I was trying to leave them there after hearing they were good for the lawn (incidentally, I DO leave them in my front lawn, because they aren't creating mounds there and they aren't causing the lawn to die). Chemical control was a Godsend. Additionally, I nearly lost my front lawn to grubs (and the moles that followed) one year. Castor oil (nontoxic) successfully chased away the moles, but chemicals knocked out the grubs and saved the lawn. I now do alternating preventative treatments (Mach2 one year - Spectracide halofenozide product; Merit the next - Bayer imidacloprid product) - less toxic chemicals that replaced the more harmful "rescue" treatments necessitated by a previous avoidance of chemicals. I'm a busy man, but my lawn is a bit of a hobby and I've researched a lot of stuff, from toxicity to effectiveness. Ultimately, I've had a little experience, and continue to gain more. First, Rhizo's entirely right - Sevin's murder on earthworms. It can be a grub "rescue" treatment (admittedly, it's what I used to rescue my lawn), if necessary, but acc. to pros I've read from, Dylox (Bayer brand 24 hr. grub killer) is stronger (on grubs), breaks down more quickly in the soil, and won't cause AS MUCH harm to earthworms (though it certainly harms them). If you've determined you need some kind of control for pests, I would recommend you read the extoxnet and EPA info on the pesticides you're looking into, to see if they're good for your application. Additionally, lurk a bit on www.lawnsite.com, where professional lawn care people post regarding their experiences with different products (in the pesticide application section). For what it's worth, I've had great success with Triazicide - both granular and liquid (granules last longer) on killing ants in the lawn. Its active ingredient, lambda-cyhalothrin, is a synthetic pyrethroid - the family of chemicals used for interior insect killing in homes and restaurants. It lasts long because it bonds to the soil; however, while it's labeled for grub killing, many say it's bonding quality lessens the effectiveness (because doesn't get deep enough in the ground). As illustrated by synthetic pyrethroids' widespread approval for interior applications, it poses little if any threat to mammals when used according to directions and allowed to dry before reentry. Re earthworms, I have TONS of them after treating with Triazicide. I'm sure it's not good for them, but it hasn't changed their population noticeably. For grubs, halofenozide (Mach2 - the active ingredient in Spectracide Grub Stop) causes grubs to molt early, which in turn causes them to stop feeding and die. Imidacloprid (Merit - active ingredient in Bayer Season Long Grub Control and the new Scotts GrubEx) is brought into the roots of the lawn (systemic) and when young grubs bite, it kills them. Both are very light toxicity to mammals, but because they are so mild, their application must be timed with the grub (several beetle species, most common Japanese and June beetles) life cycle. Pros suggest you put them down in early July so that the young grubs get them right after their eggs hatch. Run a google search to learn about the grub cycle. Merit and Mach2 have virtually no effect on earthworms. If you have let the grubs mature come fall (or if your initial treatment fails), Bayer Dylox is the product to "zap" them. It uses Trichlorfon, an organophosphate insecticide, which is much more toxic to mammals so reentry rules must be observed carefully. Some suggest beneficial nematodes for grubs (and even ants, for that matter). But I've heard from many (including pros) that they are very inconsistent, die or burrow too deeply in dry weather, and are very expensive. I'm not going to use them. FINALLY, there is one product out that combines pyrethroids with Merit - Bayer's total lawn insect killer. It combines Cyfluthrin (a pyrethroid) with Merit, to get both contact killing of insects and systemic killing of pests that feed on grass roots. I may try this next season to see if it simplifies things. I share your concerns and wish you all the best.

Sorry. This will be a long one. It always is with me. (blushing) I'm with the OP on this one. Even if no one but me ever saw my lawn, I would want it to be dark, rich green GRASS...and nothing else. (I'm known for wanting everything to be beautiful. I'm also a bit of a home body, and enjoy spending time in my yard. Many guests have remarked that, no matter where they look (on my property), there's always something beautiful. I'm always taken aback by those comments, since while that was MY goal, I never expected others to pick up on it.) Case in point about the intentional act of putting down grass, and not other (lower maintenance) plants. I own a small, remote island. I made the decision to create a lawn area and, once you include the slow-moving barge fees (3 days to get from its port to the island), labour, equipment, and materials, that lawn cost me $14,000. That obviously begs the question, why, on earth, would anyone spend a nickel putting in expensive, high-maintenance grass, only to let it be taken over by clover and other weeds??? My husband and I recently purchased a 19th century farmhouse in need of roof-to-foundation renovation. As such, I inherited a lawn that is EASILY 70% weeds, including clover so thoroughly interwoven, it would be impossible to pull by hand. I pride myself on my beautiful lawns and gardens, and can spend/have sent hours, each day, ensuring everything is healthy and how I want it. At my last home, I developed a bit of a reputation for being out weeding my lawn by hand for hours, plus how awesome my expansive lawn was. My point is, I want my lawn and gardens to be a certain way; plant the plants I want; pull the plants I don't want; unafraid to put-in the effort to achieve that. I prefer not to use any kinds of "chemicals", other than the ammonia and mild soap I include in my homemade fertilizer recipe. (My last home was a beach house. So, that only reinforced my desire to go chemical-free.) But this new-to-me house is demoralizing me...practically to the point of tears, much of it because of the state of the (laughing) "landscaping". Sure, mowing can cut off 60% of the sea of clover flowers that make my lawn look white (or dying...can't decide which). But there are still lower flowers that seem to sprout up to full height within the next 24hrs after a mow. These flowers last from late spring to fall. In short, I'm plagued by clover flowers throughout the entire season I want my lawn to look great. It's just such a shame the previous owners didn't nip the clover in the bud, when each plant was jut a little, round cluster. I love catching them early, knowing I've stopped additional infiltration. But I'm helpless, overall. Looks like I'll have to replace the entire lawn; start from scratch; do what the previous owners SHOULD have done, and pulled weeds when I first see them. I'm not really buying the whole "benefits of clover" thing, amidst a grass lawn. If I wanted a clover lawn, I would plant a clover lawn. Putting down and maintaining grass is an expense in time and resources. Clover is virtually free (since it shows up on the wind), and is seemingly mantenance-free. Since most sod and grass seed are sold with some guarantee of being weed- (and clover-) free, I just don't believe that most people who spend the money and effort to put in a grass lawn, are okay with losing any percentage of it to other, invasive, undesirable plants. I kind of liken it to suggesting that a Ferrari owner would be okay with someone switching it with a Cavalier, and just saying, 'They both get me from point A to point B, so I don't mind.' I can fully envision putting in other kinds of ground cover, and have considered it at past properties. Not being my first rodeo, I already have substantial plans to reduce the amount of lawn area, and increase planting beds. But much of this current property begs for a beautiful, thick, dark green lawn...of grass. No dandelions. No clover, but particularly no clover flowers. (I'd be more okay with clover, if not for the flowers.) The desperation was so great, I did something I thought I'd never do, and tried the iron-based WEED-B-GONE product. (Harsh, chemical herbicides have been banned in my area for years...resulting in public parks being taken over by weeds, for the most part. It's such a shame, in the sense that a healthy, well-maintained lawn is not only beautiful, but fantastic underfoot.) That is really my philosophy, beyond the aesthetic. A lawn should be cool, soft, and luxurious under bare feet. Weeds, even overgrown grass, also tend to make barefoot walking less than a joy. So far, I haven't found a way to get rid of mats of clover. The WEED-B-GONE did nothing I could notice. I'm at my rope's end on ths matter, and likely will have to pull up the entire lawn, to put down new, almost-weed-free sod, where I can physically manage pulling individual weeds as they appear. I guess I'd plead with people to pull unwanted clover plants when they're small... if not for yourself, then for the next property owner. Sure, it means time, every day, or every few days, combing the lawn, looking for weeds. Yes, it can be back-breaking and time-consuming. But that grass lawn didn't get there by accident. A grass lawn is intentional.