User Bp wrote:

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.

in an arid climate it would not be common to
see much worm life at the surface.

what type of soil do you have and how large is the area?


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.

sowbugs can do ok in fairly dry spells when worms
would go deeper and be more dormant. snails and slugs
may do ok on dewfall.


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.

putting the clippings back on the top will help,
but if there isn't quite enough moisture and the
worms are scarce it can take a while for a new
population to reestablish itself.


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-)

Darwin wasn't in an arid climate...


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.

i'm quite sure that night crawlers will not be the right worm
to put in even if there was enough moisture to support them (they
grow into their burrows through time and don't fare well when
moved or raised in captivity -- they also like a bit of clay in
the soil).

i suspect your biggest challenge is the lack of enough moisture.
the amount of money spent on irrigation setup and water over the
lifetime would likely cover the cost of doing something else
instead. putting in drought hardy plants that can withstand a
prolonged drought makes much more sense in such an arid climate.


Thanks for reading, any thoughts appreciated!

irrigating a lawn in an arid climate so that it needs to be
mowed more often is pretty foolish IMO. any worm life you
have during the wetter spells would be nice, but more likely
you'd just be feeding the birds an expensive meal if you put
worms on a lawn.

compost your veggie scraps and any spare organic materials
using a mix of native worm species and then amend your gardens
with the worm castings. mixed with the worm castings will be
cocoons and tiny worms. some of those will survive and
increase the populations, but i still think it would be an
error to expect high worm populations in an arid climate.


songbird