They're swarming and it's a timing thing. The numbers will go down soon as they don't live long, but you want to do some serious sexual interruption here, if you can, to cut back on the next wave of bugs. A modern UV zapper (or two) left on at night without other outside lights, or right beside an outside light that's inconvenient to shut off, can be a somewhat effective remedy. You supply the birth control and the chickens continue to eat organic food. Everyone wins! Work both stages. You may be surprised at June Bug grub density. This sounds like a long term project. >> Pray the nematodes have taken care of the grubs ... in the fall when they are due to hatch next. You have Fall rains after a long-ish dry spell, don't you? That might be your Fall trigger.

A typical rate for top dressing compost would be 10 cubic feet per 1000 sq. ft. of lawn. The finer the compost the better, since that will help it move down rather than sit on top of the grass. Composts sold specifically for turf top dressing are best if screened to 1/8th inch or less. If you had planned on aerating at any point in the near future, do that first and then broadcast your compost and rake it into the holes. While it has its benefits, fertilizing is NOT one of them. That's not necessarily true. For example a typical greenwaste compost is a significant source of potassium and if used at the rate I've described above a couple of times a year, you probably won't need to add any other source of potassium. To illustrate this point, take a look the analysis labeled "compost pile" in this thread that one of the members recently had done on their compost. You can see potassium in that sample at 58.1 lbs. per acre (pounds per acre is just the unit they're using to report the values). When you go through the conversions, assuming an average dry weight of 325 lbs. per cubic yard for the compost, you would be applying .35 lbs of immediately available potassium to every 1000 sq. ft. of your lawn, just like a synthetic fertilizer would give you. (I will point out for Kimmsr's sake that this immediately available / water soluble potassium has converted from an organic form to a mineralized form.) As a matter of fact, it would be supplying roughly the equivalent amount of immediately available potassium as applying 5 lbs. per 1000 sq. ft. of the ever popular Turf Supreme 16-6-8 but you didn't have to use a synthetic. The total potassium as the compost breaks down is roughly 3 to 4 times the immediately available in a greenwaste compost so two applications a year at that rate would give you a total of around 2.5 lbs. of potassium per 1000 sq. ft. which, depending on your turf species, climate, etc. could very well be all the potassium you need. Composts made from other feed stocks have different nutrient values. Just for kicks, a typical biosolids / greenwaste compost at that rate twice a year would give you 20 to 30 lbs of phosphorous per 1000 sq. ft. total and you wouldn't have to add that nutrient again for a few presidential terms.

I only mulch with compost. I apply it whenever - spring, fall, midseason (with new plantings). I doubt it makes any difference - the benefits of compost are not directly seasonally-related. It adds to soil fertility and tilth and provides the benefit of an insulating and weed suppressing mulch regardless of the time of year applied so do it whenever most convenient for you. Since I have considerably more personal gardening time in fall than I do in spring, my compost mulch tends to get applied most often after fall division, transplanting and clean-up. btw, rountine mulching with compost will negate any need to apply any supplemental fertilization in almost all gardening situations.

I would not be so categoric as to state 'should be put down in the spring' . There are many variables including climate. In mine, for example, both Spring and Autumn mulching are standard practice. An autumn mulch will protect soil from compacting winter rain. It retains warmth for those plants which flower in winter and for perennials and woody subjects which are planted throughout the winter. The soil rarely freezes and if it does only an inch or two for brief periods. An Autumn mulch can prevent freezing completely. So I stick to my contention that you can mulch whenever you have the material, if that is suitable to your climate.