----- Original Message -----
From:
y*@sfo.com
To: d*@attglobal.net ; m*@ucdavis.edu
Sent: Tuesday, November 28, 2006 7:32
AM
Subject: Re: mediterranean type nitrogen
fixing plants
You're right, compost worms (usually redworms, Eisenia foetida) flourish
only where there is abundant moisture. But also, the worms that live in
compost stay close to the surface, especially if you have a layer of moist
mulch. They are not the same as the earthworms (usually Lumbricus terrestris)
that live deeper in the soil, making tunnels to aerate the soil. I add lots of
homemade compost to my vegetable garden (which often includes many redworms),
and the only worms I ever come across when I'm digging a hole to add new
plants are the larger, muscular Lumbricus.
If you want redworm activity, one possibility is to dig your kitchen
waste directly into your soil. I don't do this (I'm still having too much fun
with my collection of compost bins), but I've known people who fertilized
backyard fruit trees by systematically digging kitchen waste (4-6 inches deep)
around the dripline of the fruit trees. If you have more than a couple trees,
by the time you get back to the first tree, the kitchen waste should already
have been digested.
If you are growing only low-water landscape plants, I'd instead do
research into mycorrhizae. If any of your plants are native to your area, look
for a local population where you can dig a spoonful of soil (for a mycorrhizal
inoculum specific to that plant). Or you can buy mycorrhizae, though these are
often generalists or include a wide range of species.
Tanya Kucak
Palo Alto, Calif.
At 12:03 PM +0200 11/27/06, de Winnaar, Charl wrote:
I have been trying to establish earthworm nodes ( dumping vermicompost in
particular areas, mulching heavily on top of it and watering
sporadically) but with little success although there seems to be activity in
winter. The main problem is that the topsoil (sand) retains little,
if any, moisture - even the mulch breakdown seems static in summer hence
little, if any, activity - bacterial or otherwise. The penalty of living
where I do, I guess.
Where exctly do you live Charl?
In a true mediterranean climate there is little
summer activity in most soils anyway. The whole soil activity is related to
the winter rainy season and many of the organisms along with the plants are
dormant in summer. They are aestivating (In summer dormancy) in the same
way as plants in temperate areas may hibernate.during the cold months.That is
why truely medit. plants often succeed better than ones from climates where
summer growing is the norm.
In just the same way as evergreen plants in other
climates may stay green through winter but stop growing, aestivating plants
keep their leaves but simply stop growing and go into an inactive stage. When
the dry period is over, soil activity fires up and the plants show
their renewed liveliness by growing and flowering.
You may prolong the growing season in some soils
by mulching and bringing in more organisms in the same way as one can put off
hibernation for a while with protective tunnels to keep out the cold, but
there are few plants and soils which do not have a down period where activity
of all life is reduced to a minimum and one does not improve the health and
growth of adapted plants by trying to keep them growing continuously. Even in
heated glasshouses many plants insist on a short period of dormancy in late
winter and if watered at that time may actually rot because their roots are
inactive and drown in the excess moisture.
Moira
