The urban myth about woodchips and nitrogen

Tim Kivi wrote:I have a rotten tree stump that breaks down more and more each year. I planted an apricot tree right next to it and it’s now the healthiest, strongest tree in my yard. I pull the tree stump apart each year as it rots, and now found apricot roots happily growing right through the whole stump.

I've seen stumps full of roots too. There's a stump in my yard cut down to ground level and there's apparently a competition among the weeds to see who gets to dominate the stump.

Hi,
So I have access to woodchips (stem, branch, leaf) from a local tree service. Mixed types possibly some black wattle in it (nitrogen fixer). I want to spread this out 5 inches thick on top of my paddock to start a large no til garden. I’d love to plant in that area in a couple of months in spring. Pumpkins, sweet potato, potato, melons.
I want to add something to the woodchip so that’s it breaks down a bit faster (as it’s mixed, I could end up with very little green matter in it if I’m unlucky) and so that it ends up being a good amendment. I’m in Australia , low phosphate soils, it’s slightly on the acidic side due to high iron content in the ground water in the gulley down from the paddock. I’m thinking cow manure, or blood meal (or both?) the manure partly because the pumpkins will send down those little roots along the stem and if it’s straight onto raw woodchip that might not be great. The blood meal as a nitrogen boost to speed up the process. Generally quite dry here.
Any thoughts? Thank you!

Jodie Usher wrote:Hi,
So I have access to woodchips (stem, branch, leaf) from a local tree service. Mixed types possibly some black wattle in it (nitrogen fixer). I want to spread this out 5 inches thick on top of my paddock to start a large no til garden. I’d love to plant in that area in a couple of months in spring. Pumpkins, sweet potato, potato, melons.
I want to add something to the woodchip so that’s it breaks down a bit faster (as it’s mixed, I could end up with very little green matter in it if I’m unlucky) and so that it ends up being a good amendment. I’m in Australia , low phosphate soils, it’s slightly on the acidic side due to high iron content in the ground water in the gulley down from the paddock. I’m thinking cow manure, or blood meal (or both?) the manure partly because the pumpkins will send down those little roots along the stem and if it’s straight onto raw woodchip that might not be great. The blood meal as a nitrogen boost to speed up the process. Generally quite dry here.
Any thoughts? Thank you!

The best way in my opinion is to put down your wood chips as deep as you can and when you are ready to plant, open up a hole in the chips down to the soil, fill the hole in with compost, and plant in that.  If you want the wood chips to break down faster, you can add your manure or blood meal, or just add it on top.  Another option is to find all the mushrooms you can, grind them up in a blender with water and pour that around on the wood chips.  The mushroom water will break the chips down much faster.

hau Jodie, to break down woodchips you need fungi. In your post you mention speed for planting this year, for best success mixing in manure and bloodmeal provides foods for bacteria, which benefit vegetable plants, so for the best of all worlds mix the chips, manure and bloodmeal before spreading over the new growing area, then spray or pour mushroom slurry over the thick "mulch" layer along with some compost tea (if you have any finished compost). Then when you come back to plant, open holes to plant in and water in with compost ttea and/or mushroom slury diluted 10:1.  

Redhawk

All of my woodchips are high in tannins and are hard. Combined with the dry climate, they keep the soil cool, but don’t do much else.

I’m really cheap.
I have 5G buckets of 50/50 composted chicken manure and coffee grounds. Also mixed in is some rabbit poop, elemental sulfur, and alfalfa. I just sprinkle some on before I add any chips.

It seems to be helping to break down the chips and my plants are looking a little tougher.

I believe that cheap is the mother of many great gardening techniques, especially the old-fashioned ones that keep making the rounds, like manure.  So simple, really - eat plants, poop, fertilize, plants grow, and so forth.  Leaves and wood chips mimic the forest floor, home of the blackest, most beautiful soil there is.  And they're cheap, or free!

Chop and drop - cheap!  Sunshine!  Saved seeds!

Okay, I'll stop now.

i have a volunteer mountain ash growing right on a 5 yr old cut spruce stump. its 6ft tall now and i grafted several pear varieties on it. its very vigorous .

I get from my neighbor both composted layer chicken manure that is just manure (with the occasional feather or broken egg) and also chicken manure that also has allot of wood shavings in it. The center ally is filled with shavings while the nest area has raised slats that eventually fills with manure. I add both of these manures to my gardens and have noticed that since adding the shavings my plants haven't had any issues of nitrogen deficiencies. My plants are still dark green and growing well. One thing I have also noticed is something growing in my gardens that wasn't growing there before I started using both the regular manure and the shavings manure is fungi. I have mushrooms and other fungi growing in my gardens now. In just a few short years my soil has changed from being 5.3 pH to 6.0 after 1 year, to 6.4 pH in 2 years and now is 6.6 pH after 3 years. The only other thing I added besides 5-7 tons of manure to the acre was about 1 ton of ash but that's spread over 3 acres so about 700 lbs. to the acre. This ash is a mixture of incinerated chickens and ash from my wood heater. Besides the pH change my soil also turned from testing medium to low in N, P, K, S, Mg, Mn, Zn, Ca, to high in all macro and micronutrients by 2nd year and now they are showing very high in all but K which is high after just 3 years. I also must say that I personally grow intensively which usually depletes nutrients as 1 acre of intensively grown okra would normally take 3 acres of conventionally row crop. Tomatoes are a little less,about 2-2.5 acres, while onions and carrots are close to 5-7 acres of conventionally grown row crops. I also rotate between 3- one acre fields and every year one of the 3 is in legumes all year (clover in fall to early spring, then peas and beans in late fall through summer and again in clover that fall after harvest) and then that 1 acre is rotated back into vegetables. With all that said, I must agree with Dr. Redhawk as me adding the shavings hasn't lowered yields, hasn't caused N deficiency, has added OM, and though my soil isn't loam quite yet it has made my sandy soil into sandy loam in what I would call a very short time.

C Rogers wrote:I get from my neighbor both composted layer chicken manure that is just manure (with the occasional feather or broken egg) and also chicken manure that also has allot of wood shavings in it. The center ally is filled with shavings while the nest area has raised slats that eventually fills with manure. I add both of these manures to my gardens and have noticed that since adding the shavings my plants haven't had any issues of nitrogen deficiencies. My plants are still dark green and growing well. One thing I have also noticed is something growing in my gardens that wasn't growing there before I started using both the regular manure and the shavings manure is fungi. I have mushrooms and other fungi growing in my gardens now. In just a few short years my soil has changed from being 5.3 pH to 6.0 after 1 year, to 6.4 pH in 2 years and now is 6.6 pH after 3 years. The only other thing I added besides 5-7 tons of manure to the acre was about 1 ton of ash but that's spread over 3 acres so about 700 lbs. to the acre. This ash is a mixture of incinerated chickens and ash from my wood heater. Besides the pH change my soil also turned from testing medium to low in N, P, K, S, Mg, Mn, Zn, Ca, to high in all macro and micronutrients by 2nd year and now they are showing very high in all but K which is high after just 3 years. I also must say that I personally grow intensively which usually depletes nutrients as 1 acre of intensively grown okra would normally take 3 acres of conventionally row crop. Tomatoes are a little less,about 2-2.5 acres, while onions and carrots are close to 5-7 acres of conventionally grown row crops. I also rotate between 3- one acre fields and every year one of the 3 is in legumes all year (clover in fall to early spring, then peas and beans in late fall through summer and again in clover that fall after harvest) and then that 1 acre is rotated back into vegetables. With all that said, I must agree with Dr. Redhawk as me adding the shavings hasn't lowered yields, hasn't caused N deficiency, has added OM, and though my soil isn't loam quite yet it has made my sandy soil into sandy loam in what I would call a very short time.

i too mulch with my chic manure. my soil is opposite of yours. heavy clay and very rocky. i planted most things on mounds or raised beds and mulch them with green chic manure. in the last 3 yrs my soil is covered with a few inches of black soil under the mulch and everything is growing like crazy. no watering needed. haven't checked ph but it must be ideal as the plant/ tree growth is phenomenal! was 5.5 before mulching. i add another 3in. every spring and its from the previous winter.

I have almost a 3/4 acre of fill on my land from a prior owner.  By fill I mean not able to even pound in a stake, hitting big rocks.  As I cannot afford to remove this fill or cover it with top soil,  I've started the process to make some soil.  I've put 5 chip drops on this fill.  It is spread over the ground with nothing added.  The chips are largely pine, oak and soft woods like alder.
So as time passes and fungi start to grow, what can I do to help with my next step (2-3 years).

Location: Oregon valley.

Hi Randy,

Welcome to Permies.

Bryant RedHawk says to put some mushrooms, ideally local ones, and water into a blender or food processor. Pour the mushroom slurry over the wood chips.

I do the same thing. It’s working well!

I found this thread looking for more info about the impact of mulching with tree prunings on soil nitrogen.  I had made some of these assumptions based on nitrogen-bonding myths, until this video of Helen Atthowe discussing her measurement of kjeldahl nitrogen.  I have so much to learn.

https://youtu.be/mQ9mwiZruSQ

Bryant (and others), if you have a chance to watch the video and comment about Helen's methods and findings, I'd love to hear your thoughts.

Marco Banks wrote:That is an important point, Chip.

Nitrogen gasses-off if it doesn't have something to grab onto.  That's why green grass clippings will heat-up your compost pile, but if you let them dry out and turn brown, all that lovely N has gassed off and returned to the atmosphere from which it came.  In this way, wood chips become a nitrogen sink that hold the element until it can up absorbed within the local ecosystem.  

Has anyone watched Joel Salatin's video about how they compost animal carcasses?  They butcher a lot of chickens, rabbits, pigs and cattle.  That's a lot of blood, guts and bones.  He spoke about a time where someone left a gate open and a train hit a bunch of his cattle.  What they do it bury the animals and guts and such in wood-chips.  They re-use the chips after about 9 months -- everything has decomposed by then.  After two cycles, they load the heavily decomposed chips into a manure spreader and spread them onto the fields.  All that N that was in the animal carcass and waste is captured by the wood chips and then transferred to the field.  Without the wood chips, it would stink, attract flies and vermin, and would just gas off all that nitrogen.

Additionally, the wood chip medium becomes the "reef" to hold all the microbial life.  Just as important as capturing the N is growing the massive volume of microbes.  More microbes = more N.  They cycle feeds itself and gets richer with time.

If you haven't seen his system, it's worth watching.  He's funny and it's such a simple and elegant way of dealing with all the animal guts, I think it's brilliant.

We did this on a massive pastured poultry farm.. all blood, guts, and feathers were composted in wood chips. When the heat and wind were just right, it smelled horrible.. but created real nice compost.

Beau Davidson wrote:I found this thread looking for more info about the impact of mulching with tree prunings on soil nitrogen.  I had made some of these assumptions based on nitrogen-bonding myths, until this video of Helen Atthowe discussing her measurement of kjeldahl nitrogen.  I have so much to learn.

https://youtu.be/mQ9mwiZruSQ

Bryant (and others), if you have a chance to watch the video and comment about Helen's methods and findings, I'd love to hear your thoughts.

Helen used good science to calculate her data. I found the video a little wordy and some portions seemed to be un-needed, but that's just me.

Redhawk

Thanks for that balanced informative post, great reasoning...so well put! Nature is amazing.