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So I wanna spend a few moments talking about macro animals.
What are macro animals?
There are things like termites, and ants, and spiders,
and pillbugs, and sowbugs those are macro animals.
Also included in the macro animal category are earthworms.
Earthworms are very important in the soil.
What they do is they actually burrow through the soil.
And in the process of burrowing, they dig channels
through the soil which allows for the movement of water down through the soil.
They actually carry organic matter with them as they move down through the soil.
So let's take a look at the impact of earthworms.
So in this cylinder right here, that's denoted nicely with the A horizon,
the E horizon, and the B horizon, you can see these horizons quite distinctly.
In the next cylinder, this is a cylinder where we've actually added earthworms.
And look at this cylinder, can you see the A, the E, and the B horizon?
Are they distinct?
No, they're not.
So one of the key things that earthworms do in addition to channeling and
carrying down organic matter.
Is they still have a tendency to actually mix the soil and
that's what happened in this particular cylinder.
There are actually three different types of worms that you can have but what we're
gonna focus on are the earthworms, or are the lumberchistrestias worms.
And what's unique about lumberchistrestias,
is that it can actually channel down or
burrow down all the way down to about five feet in the soil.
So it can move all the way down the soil profile.
And this really demonstrates it quite nicely looking at this profile right here.
Earthworms are most active during the months of April and
May and September and October.
So what earthworms do during their active phase is they migrate
out of this channel they come up to the surface.
And what they do is they sweep around all that residue
that's on the top of the soil surface.
They keep their tail sort of in the channel all right and
they come out and they sweep around all of that residue.
And they form what's called a midden, a midden is actually the earthworm's home.
So during the time of year when they're down deeper in the soil,
they'll come up, grab a piece of residue, pull it down into their hole.
And that will serve as their food source during the year.
So, one other aspect I wanna talk about is
the material that earthworms leave behind, their castings.
Their castings are really rich in nutrients.
And actually their castings as you can see from this bag right here,
it's called Soil Builder.
It says earthworm cast non toxic, all natural, organic fertilizer.
There are those occasions where we are actually interested
in trying to get a good idea of the number of soil organisms,
or soil animals that we can find in the soil.
And how do we go about doing that?
We do it by a technique called the Berlese Funnel and
this is an example of the Berlese Funnel.
So it consists of three components, all right?
We have the light source, just a low intensity light bulb essentially.
You have the funnel, which is loaded with soil.
And then you have the trap at the bottom which is
essentially filled with isopropyl alcohol so that we can trap and
preserve the organisms as the fall through the Berlese funnel.
So what happens is that the heat from
the light bulb starts to dry out the surface of the soil.
And as the soil gets drier, the soil animals like soil moisture so
they migrate further down in the funnel.
And then what happens is that the base of the funnel here, there's an opening.
And these organisms actually, because of the soil drying out, the heat from
the light bulb, they actually fall out into this isopropyl alcohol.
And are preserved so we can actually count them.
This is just an idea of the number of organisms that we
actually have found in a particular soil sample.
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