What if I Dumped 8 inches of wood chips on top of my garden?

[hit or miss]

Dumped 8 inches of wood chips on top of my garden and tilled it in? I didn't, by the way, but a friend of mine did. I believe it was a huge mistake on his part, meaning it will take huge amounts of N out of the soil while it tries its level best to break down the chips.

What say ye? This is a highly chemicalized garden too, lots of commercial ag fertilizer and even chemicals to suppress weeds.

[applestar]

I wouldn't, but I suspect results would vary depending on

1) Composted wood chips
2) Freshly cut wood/brush chips (and time of th year -- incl mature green foliage or not)
3) Dry packaged wood chips

And also whether high N /green material was also tilled in with the chips

[DoubleDogFarm]

A fertilizer like 10-10-10 or 30-30-30 would probably counteract.

Eric

[soil]

you would be following a process called ramial chipped wood. its not good for your soil in the short term because it needs time to decompose. BUT in the long run its FANTASTIC.

the fungi that eat the wood chips will also help cleanse the soil of toxins. leaving you with rich fertile soil in a year or so.

[applestar]

Good point, soil... But not if they continue with the chemical regimens, don't you think?

[soil]

But not if they continue with the chemical regimens, don't you think?

yes it would be best to stop chemical use and apply a no till method after that to preserve the fungal networks so they can do their job.

[hit or miss]

Thanks guys! The chips were probably made this winter when the power company did their yearly tree butchering to keep the lines clear. He never puts any good compost or other good materials on his garden. They did dump tons of sand in the garden a few years ago too.

It will be interesting to see what happens this summer. He works in the ag chemical and fertilizer business and is pretty convinced that is the only way to grow anything.

[Tate]

The wood chips require a lot of nitrogen to decompose. Your plants will be nitrogen deficient unless you add a lot of fertilizer. I had this issue when I got some soil that had a lot of wood chips in it. My plants suffered for a year until it broke down. This is despite adding fertilize to try to counteract it. Now the soil is great, but if I was in your case I would let it decompose more before adding it.

[DeborahL]

I did this to cover bare spots around ornamentals. None of the plants look good anymore. Never again !

[TZ -OH6]

Three years ago I tilled in 6 inches of wood chips into my clay soil. The chips were half composted with the addition of quite a bit of high nitrogen lawn fertilizer(composted from Decemper to May). I still had nitrogen trouble with certain vegetables that first year. Onions and peppers did poorly, tomatoes did fine so I think it had to do with strength/length of the root system.

You don't want to add 10:10:10 etc as that would overload the soil with P and K. Cheap lawn fertilizer is usually almost all urea/nitrogen (something like 24-0-4). You could also add blood meal. BTW, nitrogen fertilizer is made using natural gas (not oil).

The more nitrogen you add to balance out the carbon the more will get locked up in humic substances (long term "organic" nitrogen release). Without the added nitrogen the soil microbes simply burn off the carbon until it balances with the available nitrogen.

This is a different case than ramial woodchip technology. RWCT uses nutrient rich branch tips, and relatively little input (2" chips in the top 2-3 inches of soil) so the nitrogen drain is not great and it is above the root zone. I suspect that the woodchips in question are from tree removal, which is a lot of large branches and trunks chipped down. This is low nutrient wood.

How much nitrogen? The fast composting methods in this publication give some values for adding fertilizer to a given volume of compost material.

https://www.fao.org/organicag/doc/on_farm_comp_methods.pdf


hope this helps

[Wynn]

I did a deep double dig this year, when I finished my dirt was raised up about eight inches higher than my walking paths. After one of those wild spring storms I had quite a bit of erosion on my mounds.

They recently chipped hundreds of downed pine trees on our property, so I hauled a bunch of it up here, and filled in my pathways with the chips, using it to shore up the sides of my mounds. The chips have quite a bit of pine needles mixed in. It looks really nice, but I too was concerned about the wood stealing some of the nitrogen from my veggies.

I intend to mulch my mounds with straw next month (after the soil temperature heats up). Should I have any worries about pine chipped pathways?

Thanks

[TZ -OH6]

I wouldn't worry about it on walkways and edges.

Here is something about composting pine trees, although they use Christmas trees, which are mostly nutrient rich branches and needles


https://tomclothier.hort.net/page24.html

[soil]

all of my pathways are wood chips, no need to worry about the plants on the edge other than them tapping into the moist decomposing wood and growing like crazy.

[Tate]

I also have a course wood chip type mulch in my pathways around my raised beds. I don't think they have any affect on my plants either.

[Handsomeryan]

the fungi that eat the wood chips will also help cleanse the soil of toxins.

[citation needed]

[soil]

I'm assuming you want something to confirm. you could have just used google but whatever....

https://www.scribd.com/doc/4974626/Fungi-in-Bioremediation

[franktank232]

It works, but it takes a few years.

After the third season trees growing with wood chips had higher nitrogen levels while phosphorus, potassium, calcium, zinc, manganese and iron levels were all significantly higher. By the fourth season nitrogen and iron levels were significantly higher in leaf petioles from trees growing with wood chips. But potassium and calcium levels were no longer significantly greater in tree with wood chips, while phosphorus, zinc, manganese, and boron levels remained significantly higher. After two years trees growing with wood chips had less shoot growth, but by third and fourth year trees growing with wood chips had significantly more current season shoot growth. Water infiltration was significantly greater in wood chipped soils. There were more free-living bacterial (bacterivorous) and fungal feeding (fungivorous) nematodes in the chipped soils when compared to non-chipped soils. More basidiomycetes were counted in wood chipped soils and detected at higher levels with ELISA. Larger soil aggregates were found in wood chipped soils. Undisturbed wood chipped soils had more soil aggregates than disturbed soils.

https://cemadera.ucdavis.edu/newsletterfiles/The_Pomology_Post4079.PDF

[TheWaterbug]

How about using wood chips as mulch for pumpkins? I'm planting in an old horse paddock, and the previous owner piled about a cu yard of "improved" shavings near the paddock.

It's not new (we've been here nearly a year), but it's not composted, either, as it's never been turned, and it's in the shade. Is this safe/good to use as mulch?

[cynthia_h]

the fungi that eat the wood chips will also help cleanse the soil of toxins.

[citation needed]

There's a basic introduction to mycorrhizal fungi in the part of the forum devoted to Teaming with Microbes (Rev. Ed.), esp. [url=https://www.helpfulgardener.com/forum/viewtopic.php?t=25942]Ch. 19: Mycorrhizal Fungi[/url]. This knowledge has become fairly accepted not just here at THG but among many soil scientists, and it's unlikely that long-term members will consistently refer newer members to a pre-existing discussion.

The discussion includes urls of scientific papers which you probably can access directly from your work (I know my DH can from *his* work, since his connection "tells" the journals that his employer is a scientific institution; no per-article fee involved ).

Cynthia H.
Sunset Zone 17, USDA Zone 9