Regarding Composting...

huntsman · February 7, 2012

...is there any truth in the rumour that wood shavings in the compost heap deplete it of nutrients in the breaking down process, rather than adding to the heap's well being?

I'd always understood that shavings add microscopic 'goodies', but was corrected by a colleague...

rockhound · February 7, 2012

Shavings in the compost should be fine. Shavings added INTO the soil around plants could tie up nitrogen temporarily. Shavings used as mulch above ground are ok.

RayR · February 8, 2012

Microbes will consume nitrogen in your compost pile as they grow and multiply anyway. Wood shavings are a good source of carbon and minerals, but may not contain much nitrogen especially if it is aged wood, and it will break down more slowly than other less dense organic matter like leaves. Make sure you add additional sources of available Nitrogen to your pile to supplement what the microbes need and that will help them break down the wood shavings faster.

huntsman · February 8, 2012

Good to know, fellas - thanks!

So, grass cuttings, the odd bag of compost, etc for Nitrogen?

GaryStPaul · February 8, 2012

Here's a handy list with some good general info:

http://web.extension.illinois.edu/ho...materials.html

A good source of nitrogen is coffee grounds. Many Starbucks make neat bags available for the taking—not sure that's available where you are. Contrary to some opinion, coffee grounds are not acidic, but close to neutral.

Gary

Tom C zone 4/5 · February 8, 2012

Quote:

Originally Posted by huntsman

...is there any truth in the rumour that wood shavings in the compost heap deplete it of nutrients in the breaking down process, rather than adding to the heap's well being?

No wood shavings won't hurt your compost pile.

Quote:

I'd always understood that shavings add microscopic 'goodies', but was corrected by a colleague...

The myth of wood shavings depleating garden soil has been endlessly repeated.

The number of container growers here, who routinely grow their tomato plants in high percentages of wood products in their soil, aught to dispel that part of this old wives tale too.

The short answer is wood breaks down via mycellia action. Those mushrooms take up the nitrogen they need from the air.

huntsman · February 8, 2012

@ Gary -

Great list - thank you!

2 Tom - Aha! More to this concept than meets the eye, it seems...!

kath · February 8, 2012

I sprinkle a bit of alfalfa meal into a compost pile every few layers.

dice · February 9, 2012

Sawdust has a fairly high carbon-nitrogen ratio (from 175-1 to as high
as 675-1 in some studies, depending on what species of wood the sawdust
came from; average is around 400-1). Optimum for compost decay is
around 30-1.

It will still compost at higher carbon-nitrogen ratios than 30-1, but the
process slows down and the pile does not get as hot (more weed seeds
survive in it).

So it would be good to add some high nitrogen sources with sawdust
to a compost pile (grass clippings, alfalfa, tea grounds, etc; mostly
"green stuff".) If you throw in a handful of sulfate of ammonia with it as
a quick, inexpensive nitrogen fix, a gallon of wood ash or a handful of
garden lime or dolomite would be good to add, too, to keep the sulfate
of ammonia from reducing the pH excessively (earthworm "ouch").

A site that lists the N-P-K values of potential compost feedstocks:
http://www.primalseeds.org/npk.htm
(There was another one of these that was posted in an earlier thread that
was good, but it seems to have escaped my bookmarks or landed in a
different hierarchy than "garden->composting". A search through some
earlier threads on composting might turn it up.
[edit:] Ah, here we go:
http://www.thegardenguy.org/html/npk.html
[/edit])

I would expect that a handful of blood meal would be another good way
to add some nitrogen to a layer in a compost pile that is a bit high on
carbon with no negative side-effects on earthworms in the pile. It is a
good use for chicken, turkey, duck, and goose manures, too.

huntsman · February 10, 2012

Morning dice -

That's very helpful, thank you.

Actually I do have chickens and using their manure in the heap was what got the subject started, as I have been using a layer of wood shavings to carpet their living area. Sounds like it might be of added benefit to use straw or similar instead...

dice · February 10, 2012

Straw is lower carbon-nitrogen ratio than wood shavings, so will compost
faster. The wood shavings you have now would also have absorbed a fair
amount of chicken urine, which is another high nitrogen material. With that
and the chicken manure, it will probably be fine in the compost pile.

huntsman · February 11, 2012

Ah, good point.

They are very well saturated indeed!

huntsman · February 12, 2012

Quote:

Originally Posted by kath

I sprinkle a bit of alfalfa meal into a compost pile every few layers.

Good idea - thanks, kath!

kath · February 12, 2012

Quote:

Originally Posted by huntsman

Good idea - thanks, kath!

Probably picked up that tip here at T'ville and since it's a cheap amendment that I always have on hand, I've been using it ever since.

February 7, 2012	#1
huntsman Tomatovillian™ Join Date: Jul 2009 Location: Johannesburg, South Africa - GrowZone 9 Posts: 595	Regarding Composting... ...is there any truth in the rumour that wood shavings in the compost heap deplete it of nutrients in the breaking down process, rather than adding to the heap's well being? I'd always understood that shavings add microscopic 'goodies', but was corrected by a colleague...

February 9, 2012	#9
dice Tomatovillian™ Join Date: Jan 2007 Location: PNW Posts: 4,743	Sawdust has a fairly high carbon-nitrogen ratio (from 175-1 to as high as 675-1 in some studies, depending on what species of wood the sawdust came from; average is around 400-1). Optimum for compost decay is around 30-1. It will still compost at higher carbon-nitrogen ratios than 30-1, but the process slows down and the pile does not get as hot (more weed seeds survive in it). So it would be good to add some high nitrogen sources with sawdust to a compost pile (grass clippings, alfalfa, tea grounds, etc; mostly "green stuff".) If you throw in a handful of sulfate of ammonia with it as a quick, inexpensive nitrogen fix, a gallon of wood ash or a handful of garden lime or dolomite would be good to add, too, to keep the sulfate of ammonia from reducing the pH excessively (earthworm "ouch"). A site that lists the N-P-K values of potential compost feedstocks: http://www.primalseeds.org/npk.htm (There was another one of these that was posted in an earlier thread that was good, but it seems to have escaped my bookmarks or landed in a different hierarchy than "garden->composting". A search through some earlier threads on composting might turn it up. [edit:] Ah, here we go: http://www.thegardenguy.org/html/npk.html [/edit]) I would expect that a handful of blood meal would be another good way to add some nitrogen to a layer in a compost pile that is a bit high on carbon with no negative side-effects on earthworms in the pile. It is a good use for chicken, turkey, duck, and goose manures, too. __________________ -- alias Last edited by dice; February 9, 2012 at 03:34 PM. Reason: added N-P-K url

February 10, 2012	#10
huntsman Tomatovillian™ Join Date: Jul 2009 Location: Johannesburg, South Africa - GrowZone 9 Posts: 595	Morning dice - That's very helpful, thank you. Actually I do have chickens and using their manure in the heap was what got the subject started, as I have been using a layer of wood shavings to carpet their living area. Sounds like it might be of added benefit to use straw or similar instead... Last edited by huntsman; February 10, 2012 at 01:53 AM.

February 10, 2012	#11
dice Tomatovillian™ Join Date: Jan 2007 Location: PNW Posts: 4,743	Straw is lower carbon-nitrogen ratio than wood shavings, so will compost faster. The wood shavings you have now would also have absorbed a fair amount of chicken urine, which is another high nitrogen material. With that and the chicken manure, it will probably be fine in the compost pile. __________________ -- alias Last edited by dice; February 12, 2012 at 06:07 PM. Reason: trivial

February 7, 2012	#2
rockhound Tomatovillian™ Join Date: Dec 2011 Location: Tennessee Posts: 285	Shavings in the compost should be fine. Shavings added INTO the soil around plants could tie up nitrogen temporarily. Shavings used as mulch above ground are ok.

February 8, 2012	#3
RayR Tomatovillian™ Join Date: Jun 2010 Location: Cheektowaga, NY Posts: 2,466	Microbes will consume nitrogen in your compost pile as they grow and multiply anyway. Wood shavings are a good source of carbon and minerals, but may not contain much nitrogen especially if it is aged wood, and it will break down more slowly than other less dense organic matter like leaves. Make sure you add additional sources of available Nitrogen to your pile to supplement what the microbes need and that will help them break down the wood shavings faster.

February 8, 2012	#5
GaryStPaul Tomatovillian™ Join Date: Mar 2008 Location: St Paul, MN Posts: 158	Here's a handy list with some good general info: http://web.extension.illinois.edu/ho...materials.html A good source of nitrogen is coffee grounds. Many Starbucks make neat bags available for the taking—not sure that's available where you are. Contrary to some opinion, coffee grounds are not acidic, but close to neutral. Gary

February 8, 2012	#8
kath Tomatovillian™ Join Date: Jan 2010 Location: zone 6b, PA Posts: 5,664	I sprinkle a bit of alfalfa meal into a compost pile every few layers.

February 11, 2012	#12
huntsman Tomatovillian™ Join Date: Jul 2009 Location: Johannesburg, South Africa - GrowZone 9 Posts: 595	Ah, good point. They are very well saturated indeed!