I've started looking after my own lawn and garden since retiring a couple
years ago. The location is the southern Sacramento Valley in the town of
Davis, CA.

One thing that struck me is the relative scarcity of earthworms in both
the garden and lawn areas. Part of the issue is apt to be former management
practice: For probably the past twenty or more years the yard was cared for
by a commercial "mow and blow" firm. In digging in both flowerbeds and the
lawn itself earthworms are seen, but rarely; maybe one every second or third
shovelfull of dirt.

At the same time, there seem to be lots of snail, slugs, sowbugs and outdoor
cockroaches. This implies that there's enough moisture and food to support
detritivores in some numbers.

I've switched to mowing the lawn without a grass catcher and raking at least
some of the fall leaves into the flowerbeds to suppress weeds. Two years on,
the earthworm population hasn't changed much. Far as I know nobody has used
pesticide sprays in years, I used a little Sluggo until learning that it's
bad for earthworms last year.

The present drought has persuaded me to replace all the sprinklers with drip
irrigation. It's certainly more efficient than sprinklers and cheaper than
relandscaping.

Drip irrigating the lawn has required about 1800 feet of Netafim Techline CV
dripline. For now it's just stapled to the surface as I shift it around to
match the water supply to the sun load. It's possible to mow over it, very
carefully, with a reel mower.

Once the position is set, it'll be time to hide it. Trenching it in is one
option, but that's a lot of work. According to Darwin's book on earthworms,
they'll raise the soil level an inch in about five years under ideal
conditions. I have the time, but it does not look like I have the earthworms 8-)

One approach is to simply wait and see if the population increases, but the
fact it hasn't changed much in two years bodes ill for that notion. Some sort
of nightcrawler seems like the best bet, but what kind and what stocking
density are absolutely unclear to me. Alternatively, maybe something else is
wrong and adding new species won't help at all.

Thanks for reading, any thoughts appreciated!

bob prohaska