Subject: diatom. earth usage?

From: [email-masked] (Yippikiyo)
Date: Tue, 28 Mar 1995 14:54:25 UNDEFINED

Okay, I bought the diatom. earth to protect my garden from caterpillars and 
cutworms the organic way.  I thought there would be info on how to use it on 
the bag but the only directions are how to use the earth (which doesn't even 
look like earth but instead like flour) in a swimming pool filter!  Did I make 
a boo-boo?  This is the right stuff, right?  How much should I use in and/or 
around the plants, do I sprinkle it on the dirt or on the plants?  If it rains 
or I water do I need to reapply?  Someone said to make a mixture of d.e., 
soap, and water and spray the plants liberally, do you agree?  When should I 
apply it and for how long?  Is it dangerous to me, my 1yr old, my cats or dog?
I have tomatoes, broccoli, spinach, lettuce,and various herbs, any suggestions 
are greatly appreciated!
Yippikiyo

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From: [email-masked]
Date: 28 Mar 95 18:34:58 -0600

> I have tomatoes, broccoli, spinach, lettuce,and various herbs, any suggestions 

Diatomaceous earth is the "shells" of tiny algae called diatoms.  It is
almost chemically pure silicon dioxide, same stuff as sand and glass.
It is non-toxic to mammals if eaten, does not decompose, and works until
the particles are carried down in the soil and diluted.

It works on insects by "scratching" their exoskeleton, allowing drying
to take place.  It is non-selective, so it gets the good guys with the
bad guys.

Supposedly, the diatomaceous earth sold for swimming pool filters has
been heated and the shells are therefore "rounded" and don't scrtch
through the exoskeleton.  Organic gardeners will tell you to buy only
"natural grade".  I've examined samples of swimming pool diatomaceous
earth and "natural grade", and I cannot tell them apart microscopically.
I don't know whether labeling varies regionally, or the "natural grade
stuff" is a Garden Urban Legend.

DE is supposed to be used as a paint, in a slurry with water, or as a
dust, encircling stems.

I cannot tell you how well it works.  I personally consider it too
hazardous to use.  (I know, it's non-toxic... BUT....)
Small particles of airborne silica produce a lung disease called
"silicosis" or "miner's lung".  DE has not been directly implicated
in silicosis when used in home gardens, but it has been in people who
commonly handle it.  In addition, I *suspect* that we will find that
many "idiopathic" (without known causes) cases of emphysema, bronchitis,
COPD, and perhaps lung cancer, will be traceable to being around lots
of inert dusts.  I do know that DE will trigger my asthma.  

Kay Klier  [email-masked]

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From: [email-masked] (Yippikiyo)
Date: Tue, 28 Mar 1995 21:02:05 UNDEFINED

In article <[email-masked]> [email-masked] writes:
>From: [email-masked]
>Subject: Re: diatom. earth usage?
>Date: 28 Mar 95 18:34:58 -0600

.  It is
>"silicosis" or "miner's lung".  DE has not been directly implicated

Wow, I had no idea.  What would you use to protect your garden from critters 
rather than DE?  And are there any other uses for DE besides pool filters and 
pest control?  I'd heard that some people feed it to their dogs but I don't 
know why, do you?
I really appreciate your insight and input.  Thanx!

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From: [email-masked] (Una Smith)
Date: 29 Mar 1995 18:20:58 GMT

[email-masked] writes:

>in silicosis when used in home gardens, but it has been in people
>who commonly handle it.

Diatom shells or "tests" are amorphous SiO2:  in short, glass.  They
are commonly used as very fine grade abrasives.  Like fiberglass, 
diatomaceous earth shouldn't be inhaled.  But, unless you find that
you are sensitive to it in some manner, like Kay is, it's probably
quite safe to use on your garden.  Note:  SiO2 is used by some plants,
especially grasses, to (we believe) discourage herbivory by grazing
animals, because right about the point at which grasses appear in the
fossil record, mammalian herbivores (plant-eating mammals, like modern
horses, cows, etc.) began to evolve much longer teeth.  The idea is
that the SiO2 content of the grasses wore down the herbivore's teeth.

-- 
	Una Smith			[email-masked]

Department of Biology, Yale University, New Haven, CT  06520-8104  USA

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From: [email-masked]
Date: 29 Mar 95 17:06:36 -0600

In article <[email-masked]>, [email-masked] (Yippikiyo) writes:
> rather than DE?

Well, I either let the plants and the bugs fight it out for themselves, or
I use some simple stuff like toilet paper roll collars around tomato
plants for cutworms, or I hand pick creepy-crawlies that I don't care
to have in my garden.  Mostly I just let the plants fend for themselves.

>  And are there any other uses for DE besides pool filters and 

Toothpaste, polishing agents for glass, lab filtration and column 
chromatography, and lots of other industrial uses.  The folks who
feed it to their dogs think they are worming them... haven't known
it to work all that well for that purpose.

I should emphasize that I'm probably a bit overcautious about airborne
particulates; most of my family has died of various lung diseases,
gasping for breath.  I'd just as soon not have it happen to me, too.
I'll use DE in the lab for column chromatography, but my columns are
packed wet and discarded wet, and I use a good dustmask when I work with
the stuff.

Kay Klier  [email-masked]

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From: [email-masked]
Date: 29 Mar 1995 17:12:04 GMT

Yep, you bought the wrong stuff.  If it says to use it in a   
swimming pool filter, the d.earth has been processed/ground into   
an even finer dust.  This processing makes it useless for organic   
gardening since it eliminates the razor-sharp micoscopic edges on   
the dead sea critters.  Those razor-sharp edges will slice up   
bugs that crawl over it and then they die from dehydration. 
 
Go to a garden/landscape shop to buy organic d.earth or go to a   
farm supply store.  They'll show you how to use it (especially   
the farm supply stores) and sell you the dusters to apply it   
with. 
 
Good luck. 
 
Sam

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From: [email-masked]
Date: 30 Mar 95 14:33:57 -0600

In article <[email-masked]>, [email-masked] (Una Smith) writes:
> quite safe to use on your garden. 

Una, I agree, it's probably safe in most instances.  I just find it 
an unnecessary risk.  Like any sort of toxicology problem, you're 
going to find some individuals with a greater susceptibility at
a lower dose, and some that can handle quite high doses.  That's
what makes coming up with numbers for TLV's and other industrial
exposure limits so interesting.  It all comes down to the amount
of risk you wish to accept, and considerations of chronic vs. acute
exposure... sometimes policy making decisions like these are a
little more art (or at least SWAG) than pure science.  Soooner or
later you have to take the best data you have and draw some conclusions.
I'm sort of a belt-and-suspenders type, so I'll stick with my
toilet paper roll collars and hand picking.  (Besides... I get
to name those creepie-crawlies that I'm hand picking after my
favorite people... "Bye-bye, Lysenko...  So long,  Dr.....  ;-) )

that some individuals are affected more 

 Note:  SiO2 is used by some plants,
> that the SiO2 content of the grasses wore down the herbivore's teeth.

Aren't those silica cells fun to look at?  The fact that the idioblasts
are so stable makes 'em handy for fossil grass ids, too!

Kay

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From: [email-masked] (Una Smith)
Date: 29 Mar 1995 18:20:58 GMT

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From: [email-masked]
Date: 29 Mar 95 17:06:36 -0600

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From: [email-masked]
Date: 29 Mar 1995 17:12:04 GMT

Good luck. 
 
Sam

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From: [email-masked]
Date: 30 Mar 95 14:33:57 -0600

Kay