"nswong" wrote in news:2l7avjF97tkbU2@uni-
berlin.de:

Hello Wong,

Hi Salty, g

"Salty Thumb" wrote in message
...

After finished another reply to your posting, I realize it is too late
to go to my land now. :-(

Never mind, since I'm in good form to write, it's better do my writing
now. :-)

As I understand it, for optimal decomposition, you should have a C/N
ratio of 30:1. I have read that wood chips and sawdust will reduce
nitrogen availability during decomposition when used as mulch or in a
compost pile, and I assumed that was because of the high carbon
content. Newspaper has approximately between 1/2x and 5x the carbon of
sawdust (both primarily celluose).

[1] http://compost.css.cornell.edu/calc/lignin.html

Diamon also having high C/N ration, I can assure you it will not
reduce the N available to plant when use as mulch. g

Diamonds (?) do not contain any biologically accessible carbon.

It really depend on the available carbon instead of the total carbon
contain.

Both newspaper and sawdust have high cellulose percentage. Sawdust is
reported to reduce nitrogen availability when used in a compost pile.

I believe mulch will reduce N available to plant when the carbon(in
liquid form) leach to the soil in rain, but not when there is no water
soluble carbon are present in mulch.

Many forms of N are water soluable and is leached away by water without
any interaction with C, mulch or newspaper. You may actually get
additional N during rain.

In my impression, newspaper does not contain much water soluble
carbon. It need enzyme to convert it, and that is a slow process.

Cellulose is broken down by actinomycetes.

hmm, according to [1], you are right, at least for lignin
decomposition. A certain quantity of additional nitrogen will speed up
anaerobic decomposition, but excess has little or no effect. It does
not say about cellulose.

Adding N more than substrate(mulch, soil, compost...) can hold are
waste of money, the extra N will lost in air or worse, leach to the
groundwater.

If I'm not wrong, cellulose are not one of the form of carbon that
directly available by bacterial.

Despite the name and superficial resemblance, actinomycetes are
prokaryotic bacteria, phylum actinobacteria. (Fungi are all eukaryotic.)

Mulch supress weeds not just because the physical blocking ability,
it can also leach out some chemical harm weeds. Critters in mulch
will also help to supress weeds.

Yes and also fungi.

I thinks I should use "soil live" instead of critters. g

'soil life'

My point is if you wanted to increase nitrogen availability to the
soil to compensate for newspaper decomposition loss (if there actually
is any) you could add to the soil, but actually if you wanted
newspaper for nutrients (as opposed to weed control), you should
probably do that in the compost pile and not in the flower bed.

I agree.

I agree, the amount of nitrogen fixated (if any) by electrostatic
effect over a surface is probably minor, but I mention it because
occasionally you hear about people growing huge tomatoes with panty
hose (nylon) and the effect may be similar.

I don't now what is panty hose(nylon).

Panty hose is something women wear on their legs. I do not know why.

I do read tomatoe will grow larger when using red "plastic sheet"? as
mulch due to the infrared and the higher warm of soil.

Yes, I have heard that, too. I think there was a Clemson or other
Southern US university study. I am waiting for them to come out with a
UV resistant landscape fabric version. g

For this I do facing problem to explain my view. In bussiness, we
talk about total cost of ownership. In here we talk about in the
total life span of the product, how much cost involve and how much
the return get.

In these terms, landscape fabric is USD$10 / 150 sq. ft (14 sq.
meter), with a life span of 15 years when installed properly, plus the
starting cost of mulch, USD$2-3 / 3 cubic feet (for large pine bark
nuggets) at recommended coverage rate of 4-6 inches (10-15 cm, mine is
probably less than 2 inches) and periodic replacement cost for wind or
decomposition loss. Other factors: labor savings in amount of time
spent weeding, labor increase in adding amendments, productivity
comparisons if relevant, etc. My recommendation is based on use for a
home flower bed, not a large scale or intensive operation.

To explain my view, this will become a very long posting.

One of the example of the cost I refer are stocking cost, purchasing
cost(time spend on searching, barginning...), disposing cost(collect
and send to landfill..._)...

It is not necessary, I do not think the orginal poster is concerned with
those things. Have you read the sci.bio.agriculture group?

In my experience, earthworms (not necessarily nightcrawlers) will
continue to crawl until it finds an existing opening and not attempt
to chew through paper to find an exit. In this way, I assume it is
similar to fabric, although there is no way the earthworm will be able
to chew through landscape fabric. These observations were in
daylight, so may not be representative of normal behaviour.

From what I read, all the earthworms will not like to expose under the
light.

They also prefer to avoid becoming lunch.

You may find earthworms gether around the opening of landscape fabric
can be due to they need to feed on plant debris at night time and seek
shelter in the soil under landscape fabric at day time. Earthworm
happen to around opening are the only survival, earthworm under the
landscape fabric that can't manage to find the opening are long dead.

If you read the link I posted earlier, it classifies earthworms in 3
groups. One of them i don't remember and is probably not relevant. The
other two are nightcrawlers and regular earthworms. It said that
nightcrawlers have permanent burrows, these are the ones you are talking
about that come out at night to feed on plant debris. Another link I
provided gave the population density for a certain species at some test
location as 0-7 per sq. meter. At this rate, and the size of my flower
bed, I think any detrimental effect by landscape fabric is minimal. I
think, since it is a worm, eventually it will reproduce at a sufficent
rate to exploit any available opening. The other kind of earthworm does
not live in static burrows and only comes out during times of rain. I
would guess that being subterranean, they would also be minimally
affected by landscape fabric.

Look at all short of filter we use, they all block. Do a test,
remove the mulch on top of your landscape fabric, put some water on
top of it, see how long it will pass through.

I do not think this is a problem. When it rains, I do not have a
problem with drainage, so the water must go down some where, even if
the gutters are removed (and rain falls directly from the roof to the
flower bed). If you test the fabric by itself, fast moving water (such
as from a faucet) will be deflected from the surface, but slow water
(as typical with mulch impeded flow) will drain. If it weren't
porous, you might as well just you regular black polyethylene
sheeting.

I'm refer to no matter how porous landscape fabric are, it hole will
block by something by one day, either it's a plant root or clay or
something.

I don't think plant roots are impermeable to water. I don't know how a
chunk of clay is going to get into my flower bed. It has been several
years and I have no problems with water blockage. Even if some clay or
other amendment (as below) were spread over the fabric, water is a very
effective solvent and while the clay or amendment is not guarranteed to
pass, the water certainly will.

Mulch have critters making tunnel in it, except there is little
critter in it.

I could be wrong, but I just don't see macroscopic organisms eating
vertical holes through newspaper to gain surface access.

Critter need shelter, food, water and air to survive. In search of
these resource, they will moving around, and creating tunnel through
everything if they can.

E.g. critter will move deeper in soil to avoid the heat at day time,
move to survice of soil to get food, move deeper when soil surface are
dry, move to survice when ground water level are high.

Plant will also grow throug the newspaper in search of resource, be it
shoot from below or root from top.

You can try this experiment: Cover some soil with newspaper. Time how
long it takes to develop an opening. It takes over 2 months in a
temperate climate. Any holes that develop are not from macroscopic
organisms. Plants will grow through, but those opening are not available
to macroscopic organisms (being blocked by the plant). Gradually, in wet
areas of the paper, actinomycetes or other microscopic organisms will
weaken the newspaper until a hole forms or mechanical action (wind,
water, etc) hastens the break down. I will be surprised if you can come
up with any large organism (other than termites, paper wasps and people)
that will deliberately make a hole in the newspaper. To be fair, cover
half the newspaper with organic mulch (I have not tried this) and see
what happens. You can cover the other half with a banana leaf or
something if you are worried about sun effects on organisms (you can take
the leaf off when it rains or artifically add water to simulate tho
condition). I predict the only difference is that mulch side will have
accelerated decomposition (1 month to first hole vs. 2 months).

I'm refer to those nutrien that resolve in water as liquid form.

You mean nutrients that are dissolved in water? It is possible that
the fabric (different kinds of fabric vary) will filter the dissolved
nutrients (in the same way a paper coffee filter may filter salt from
seawater). I do not know, so I would not rely on it.

Yes, I do mean "dissolve". Thanks for your correction. :-)

I do doubt about the hole of landscape fabric are as small as this.
If it do, I can assure you neary all the rain will end up as run off,
and there will be not enough water to keep plant survive without a
drip irrigation system.

It's not just the size of the hole but also any electrical or chemical
effects that may cause what ever you are adding to clump together
(similar to hard water calcification of drain pipes on a smaller scale).
Also, the landscape fabric regardless of the holes may be semi-porous to
water. That is not necessarily true for the solute. [by 'hole' in this
case, I'm refering to the factory made approx. millimeter sized openings
uniformly distributed over fabric area, not the openings made by users to
plant through.]

Landscape fabric can become embeded with roots attempting to
penetrate from below, but the removal of such fabric is of minor
difficulty.

From what I read, those user of landscape fabric donot take it as
"minor difficulty". g

haha, perhaps the Green lacking in my Thumb is made up with my
Incredible Hulk strength.

If there is some bush grow on top, and rooting through landscape
fabric, it still will be a mess even you manage to get "Incredible
Hulk" to help you. g

Your peanut groundcover is more likely to grow to 2 meters tall and start
dancing around with a top hat, cane and monocle.