hort.net Seasonal photo, (c) 2006 Christopher P. Lindsey, All Rights Reserved: do not copy
articles | gallery of plants | blog | tech blog | plant profiles | patents | mailing lists | top stories | links | shorturl service | tom clothier's archive0
 Navigation
Articles
Gallery of Plants
Blog
Tech Blog
Plant Profiles
Patents
Mailing Lists
    FAQ
    Netiquette
    Search ALL lists
    Search help
    Subscription info
Top Stories
Links
sHORTurl service
Tom Clothier's Archive
 Top Stories
Disease could hit Britain's trees hard

Ten of the best snowdrop cultivars

Plant protein database helps identify plant gene functions

Dendroclimatologists record history through trees

Potato beetle could be thwarted through gene manipulation

Hawaii expands coffee farm quarantine

Study explains flower petal loss

Unauthorized use of a plant doesn't invalidate it's patent

RSS story archive

RE: Heavy Metals in Garden Soil

  • Subject: RE: [cg] Heavy Metals in Garden Soil
  • From: "Jack Hale" jackh@knoxparks.org
  • Date: Wed, 11 May 2005 09:30:25 -0400

I don't want to jump on anybody in the list serve, and I acknowledge that my
point of view is somewhat more liberal than others here, but I'd like to add
a couple of points.
1. My understanding has always been that compost does not always or
typically affect soil pH and that adding organic matter to soil helps to tie
up soil lead.  I'm not a chemist so all this stuff seems a bit magical, but
that's what I have heard.  Regardless, Karen's statement - Compost should
not be used in gardens with high amounts of lead, compost increases the pH
and lead is absorbed more by plants under conditions of low pH. - is
actually self-contradictory.  Maybe a little more research is required
before we express too much certainty.
2. My understanding of the vocabulary is that lead is toxic and too much of
it in the wrong place is hazardous.  Part of the issue is deciding what
constitutes hazard.  EPA has different soil lead levels for different uses.
I don't have that information handy, but suffice it to say that from their
point of view you can tolerate higher levels of lead under a parking lot
than in a garden.  I don't know what is behind the Quebec standards, but
they are certainly more conservative than EPA's.  Regardless, both are based
on some idea of tolerable exposure.  In other words, both assume that some
exposure to lead should be considered acceptable.  Both also recognize that
it is probably not possible or practical to remove all lead from the
environment.  So, if we accept those connected assumptions, we can look at a
garden and decide on acceptable exposure and practical management.  For
instance, if we have generally good quality soil on a site and lead levels
just over the standard we want to work with, we may decide that dilution is
better (it is certainly cheaper) than trying to find all the lead and remove
it.  Soil of good tilth is increasingly rare in cities.  We may want to hang
onto it and try to fix its problems rather than sending it off to become
landfill cover or something.  The image of throwing the baby out with the
bathwater comes to mind.
Anyway, those of us who want healthier cities are in a battle on lots of
fronts.  Here's to finding good strategies that work well in our situations.
JH

Jack N. Hale
Executive Director
Knox Parks Foundation
75 Laurel Street
Hartford, CT 06106
860/951-7694
f860/951-7244


-----Original Message-----
From: community_garden-admin@mallorn.com
[mailto:community_garden-admin@mallorn.com]On Behalf Of Mike McGrath
Sent: Tuesday, May 10, 2005 8:40 PM
To: Deborah Mills; adam36055@aol.com; community_garden@mallorn.com
Subject: Re: [cg] Heavy Metals in Garden Soil

Yes, please; the only sure way to make lead safe is to cart it away.
                                    ---McG
----- Original Message -----
From: "Deborah Mills" <deborah@greencure.org>
To: <adam36055@aol.com>; <community_garden@mallorn.com>
Sent: Tuesday, May 10, 2005 7:57 PM
Subject: Re: [cg] Heavy Metals in Garden Soil


>I totally agree with Karen Jones and Adam's words.
>
> Deborah
> ----- Original Message -----
> From: <adam36055@aol.com>
> To: <community_garden@mallorn.com>
> Sent: Tuesday, May 10, 2005 3:51 PM
> Subject: Re: [cg] Heavy Metals in Garden Soil
>
>
>> Again, friends, lead is bad news, and unless you have really careful
> gardeners who really, really REALLY watch their kids, you have a dangerous
> situation to deal with. I mean how can you tell a kid not to take a
> sunflower home to Mommy,  even though it's filled with and has to be
> disposed as toxic waste because of the lead it has soaked up?  Do you have
> to paint a "Death's Head," on its face?
>>
>> I love this list, and the ingenuitiy of many of the gardeners, but when
>> it
> comes to kids and a really nasty environmental poison, caution and the
> most
> prudent practices have to be followed.  Karen Jones is really right about
> lead - please listen to her.
>>
>>
>> Everbest,
>> Adam Honigman
>> Volunteer
>> Clinton Community Garden
>>
>>
>>
>> -----Original Message-----
>> From: Karen Jones <k.jones@uwinnipeg.ca>
>> To: community_garden@mallorn.com
>> Sent: Tue, 10 May 2005 12:42:29 -0500
>> Subject: [cg] Heavy Metals in Garden Soil
>>
>>
>> We got our urban garden tested for heavy metals last year and found lead
>> 119 ppm, the standards we used werethose of  the government of Quebec,
>> which has the strictest standards in Canada.They consider land to be
>> toxic at 130 ppm.  Lead will accumulate in leaves (not petioles) and
>> roots. If you peel carrots they are safe to eat because the lead
>> accumulates near the epidermis. Rhubarb is safe to eat. Lettuces,
>> Spinach, Cabage etc. is not safe to eat. All fruits are safe to eat,
>> because plants somehow do not let heavy metals into the seeds. Canola
>> and Sunflowers are good for remediation, but they then must be treated
>> as toxic waste. Compost should not be used in gardens with hight amounts
>> of lead,  compost increases the pH and lead is absorbed more by plants
>> under conditions of low  pH. Children under two should not be permitted
>> into these gardens at all, apparently 25% of young children eat soil
>> (pica) and children  accumulate heavy metals at faster rates than
>> adults. You may accumulate lead all your life and then when some
>> tramautic physical event occurs the lead will leach out of your bones
>> and you begin to lose your way in life. Please remember that no levels
>> of lead are safe. You have to have a really educated group of gardeners
>> to be able to garden safely where heavy metals are concerned. Raised
>> beds, are they sustainable? I don't think so. The David Suzuki
>> Foundation helped us to interpret the results.   Karen
>>
>>
>> ______________________________________________________
>> The American Community Gardening Association listserve is only one of
> ACGA's
>> services to community gardeners. To learn more about the ACGA and to find
> out
>> how to join, please go to http://www.communitygarden.org
>>
>>
>> To post an e-mail to the list:  community_garden@mallorn.com
>>
>> To subscribe, unsubscribe or change your subscription:
> https://secure.mallorn.com/mailman/listinfo/community_garden
>>
>>
>> ______________________________________________________
>> The American Community Gardening Association listserve is only one of
> ACGA's services to community gardeners. To learn more about the ACGA and
> to
> find out how to join, please go to http://www.communitygarden.org
>>
>>
>> To post an e-mail to the list:  community_garden@mallorn.com
>>
>> To subscribe, unsubscribe or change your subscription:
> https://secure.mallorn.com/mailman/listinfo/community_garden
>
>
> ______________________________________________________
> The American Community Gardening Association listserve is only one of
> ACGA's services to community gardeners. To learn more about the ACGA and
> to find out how to join, please go to http://www.communitygarden.org
>
>
> To post an e-mail to the list:  community_garden@mallorn.com
>
> To subscribe, unsubscribe or change your subscription:
> https://secure.mallorn.com/mailman/listinfo/community_garden


______________________________________________________
The American Community Gardening Association listserve is only one of ACGA's
services to community gardeners. To learn more about the ACGA and to find
out how to join, please go to http://www.communitygarden.org


To post an e-mail to the list:  community_garden@mallorn.com

To subscribe, unsubscribe or change your subscription:
https://secure.mallorn.com/mailman/listinfo/community_garden


______________________________________________________
The American Community Gardening Association listserve is only one of ACGA's services to community gardeners. To learn more about the ACGA and to find out how to join, please go to http://www.communitygarden.org


To post an e-mail to the list:  community_garden@mallorn.com

To subscribe, unsubscribe or change your subscription:  https://secure.mallorn.com/mailman/listinfo/community_garden





 © 1995-2015 Mallorn Computing, Inc.All Rights Reserved.
Our Privacy Statement
Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index