[Cob] using hay instead of straw

[Bernhard Masterson]

HI Kristen,
   Some hay will work for cob but straw will work better.  The previous posts in response to your question are correct.  The one piece that they are missing is the carbon, nitrogen, and moisture component of straw and hay.  Hay is harvested before the plant is completely dried and for its nutritional value so it retains the nitrogen and other enzymes that make plant material nutritious to critters.  Because of that, hay is more prone to decomposition in the wall.  Straw is from cereal grains, which are harvested only after the plant is fully dried out and all the energy has gone to the seed head.  The stalks of cereal grains (straw) is very dry and very high carbon and low nitrogen.  This makes it far more stable in cob walls or straw bale walls.
   If you are going to use hay, use the hay that has the most long dry grass stalks and/or sort them out.  Straw is cheap enough that I would recommend purchasing it.  In the long run I feel it is well worth the investment.

hope this helps,
- Bernhard 


____________________________________bernhard_masterson at hotmail.com

Natural building instruction and consultation




> 
> Message: 1
> Date: Mon, 20 Jul 2009 08:26:01 -0600
> From: "Kristen Davenport" <kristen at boxcarfarm.com>
> Subject: [Cob] using hay instead of straw
> To: <coblist at deatech.com>
> Message-ID: <6BB93C57FB714BA59DB8153B2DFBA2DA at KristenPC>
> Content-Type: text/plain;	charset="iso-8859-1"
> 
> HI there
> Most of the cob books and experts have said we should not use hay for building with cob, rather than straw, but I'm completely at a loss about WHY. I've received all kinds of different answers.... "It will sprout" (so what)... "It's not as strong" (huh??)
> 
> To me, none of this makes any sense.
> 
> For instance, in the Becky Bee book she says "Do not use hay. It decomposes." Yet a few sentences later she states, "If you're an ambitious purist,  you can gather your own grass stalks or experiment with other plant fibers." Well, HELLO, what do you think hay is? Grass stalks. Not to mention, as an avid composter, I can tell you that "straw" decomposes just the same as "hay"... and "hay" can mean anything from brittle stalks with seed heads to thick straps of wide grass to bales of weeds and wild rose stalks and willow branches..
> 
> Can anyone give me a reason that makes sense to me why we shouldn't just use my neighbor's weedy hay for building with cob?
> 
> Thanks.
> 
> Kristen
> 
> ------------------------------
> 
> Message: 2
> Date: Mon, 20 Jul 2009 08:49:43 -0700
> From: "Dulane" <silkworm at spiderhollow.com>
> Subject: Re: [Cob] using hay instead of straw
> To: "'Kristen Davenport'" <kristen at boxcarfarm.com>,
> 	<coblist at deatech.com>
> Message-ID: <20090720154935.5BBED614F81 at mail-in04.adhost.com>
> Content-Type: text/plain;	charset="us-ascii"
> 
> 1. Straw is the stalks of a grass plant, like oats or wheat. Hay is a leafy
> plant like alfalfa or other legume, like clover.
> 2. Hay has ample nutrients, straw does not...just fiber.
> 3. Straw doesn't compost quickly, hay does.
> 4. Mice and voles love eating hay, but may build nests in loose straw.
> 5. Hay costs more, because it is a feed. (Only mushrooms and mold really
> like eating straw.)
> 6. Straw costs less because it is only good for bedding or other application
> that calls for nearly inert biomass.
> 
> I recently harvested some of our field grass to use for cob, but I made darn
> sure I did it before the seeds had a chance to head up, and tore the heads
> off those that were starting to go to seed. I would definitely use local
> grasses if you have access to them, but remove all the seeds.
> In my little cob house, I only used about 4 bales of straw. When I started
> the project, they were $7 per bale, but I paid $14 for the last bale.
> 
> 
> -----Original Message-----
> From: coblist-bounces at deatech.com [mailto:coblist-bounces at deatech.com] On
> Behalf Of Kristen Davenport
> Sent: Monday, July 20, 2009 7:26 AM
> To: coblist at deatech.com
> Subject: [Cob] using hay instead of straw
> 
> HI there
> Most of the cob books and experts have said we should not use hay for
> building with cob, rather than straw, but I'm completely at a loss about
> WHY. I've received all kinds of different answers.... "It will sprout" (so
> what)... "It's not as strong" (huh??)
> 
> 
> To me, none of this makes any sense.
> 
> For instance, in the Becky Bee book she says "Do not use hay. It
> decomposes." Yet a few sentences later she states, "If you're an ambitious
> purist,  you can gather your own grass stalks or experiment with other plant
> fibers." Well, HELLO, what do you think hay is? Grass stalks. Not to
> mention, as an avid composter, I can tell you that "straw" decomposes just
> the same as "hay"... and "hay" can mean anything from brittle stalks with
> seed heads to thick straps of wide grass to bales of weeds and wild rose
> stalks and willow branches..
> 
> Can anyone give me a reason that makes sense to me why we shouldn't just use
> my neighbor's weedy hay for building with cob?
> 
> Thanks.
> 
> Kristen
> _______________________________________________
> Coblist mailing list
> Coblist at deatech.com
> http://www.deatech.com/mailman/listinfo/coblist
> 
> 
> 
> 
> ------------------------------
> 
> Message: 3
> Date: Mon, 20 Jul 2009 11:20:15 -0400
> From: Georgie Donais <georgie at busygirl.ca>
> Subject: Re: [Cob] using hay instead of straw
> To: Kristen Davenport <kristen at boxcarfarm.com>
> Cc: coblist at deatech.com
> Message-ID:
> 	<5763d3220907200820mf7fcd88v696ef7f1d50a2134 at mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
> 
> Kristen,
> 
> I think that generally, straw refers to the cellulose stalks of a grain
> plant, whereas hay can mean the leaves, stalks and seedheads of a green
> manure crop such as alfalfa, clover, bromegrass and the like.
> 
> Straw:
> - No real food value
> - Long, skinny fibres are convenient to work with
> - Good tensile strength
> 
> Hay
> - Lots of good eating there. As they say, hay is for horses.
> - Prone to sprouting and rotting
> - Probably a bit more difficult to work with, with all the plant parts
> present
> - Possibly less tensile strength as it's not strictly stalks
> 
> When people say to avoid building with topsoil, I think it's a similar
> argument. Topsoil built up over eons is far too valuable to be used as a
> building material. Better to remove it for gardens and use the
> free-of-organic-matter subsoil for building.
> 
> That said, why not experiment? I would just avoid the wild rose stalks; not
> so comfortable for barefoot cobbers :)
> 
> Georgie
> 
> On Mon, Jul 20, 2009 at 10:26 AM, Kristen Davenport
> <kristen at boxcarfarm.com>wrote:
> 
> > HI there
> > Most of the cob books and experts have said we should not use hay for
> > building with cob, rather than straw, but I'm completely at a loss about
> > WHY. I've received all kinds of different answers.... "It will sprout" (so
> > what)... "It's not as strong" (huh??)
> >
> > To me, none of this makes any sense.
> >
> > For instance, in the Becky Bee book she says "Do not use hay. It
> > decomposes." Yet a few sentences later she states, "If you're an ambitious
> > purist,  you can gather your own grass stalks or experiment with other plant
> > fibers." Well, HELLO, what do you think hay is? Grass stalks. Not to
> > mention, as an avid composter, I can tell you that "straw" decomposes just
> > the same as "hay"... and "hay" can mean anything from brittle stalks with
> > seed heads to thick straps of wide grass to bales of weeds and wild rose
> > stalks and willow branches..
> >
> > Can anyone give me a reason that makes sense to me why we shouldn't just
> > use my neighbor's weedy hay for building with cob?
> >
> > Thanks.
> >
> > Kristen
> >
> 
> -- 
> ~~~~~~~~~~~~~~~~~~~~~~~~~~
> http://mudandmusings.blogspot.com/
> 
> 
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> 
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> 
> End of Coblist Digest, Vol 7, Issue 133
> ***************************************