Hugelkultur -- good wood, bad (allelopathic) wood

Herbally Black walnut is used as a fungicide (athletes foot, candida, etc) recently i read an article that said black walnut trees tend to favor grasses, so that suggests to me the alelopathic effect might be greater for plants that prefer fungally dominated soils.

Has anyone heard if brassicas grow well near black walnut, as these tend to favor bacterial soils?

perhaps a hugel bed with black walnut would be ok for them, although again the idea of using anything but odd rotted pieces for a hugel bed is appalling, black walnut is a beautiful durable wood that should be on display, not buried prematurely

As always, I think it inappropriate to use good construction lumber in a hugelbeet; that's what the irregular bits are for. Some would even argue that good firewood should be sold where there's a market before used in a hugelbeet. I mean, it seems wasteful to put in the ground to rot something that could be sold.

-CK

I've been to 4 hugelkultur projects belonging to others and to my own. None of them have dumped good, useful wood into the pile. The quantity of wood available on Vancouver Island is massive. The little bit that goes into wood stoves, pales in comparison to the amount that is burned in slash piles. Last week I saw a giant pile of stumps stacked to about 35 feet high. These will be burned during the rainy season when forest fire is not an issue. I estimate the pile to weigh 200 tons. It's 3 miles from my place. I plan to fill several garbage cans with ash. My soil is acidic. Wood ash is alkaline.

My neighbor cut down 4 mature pine and fur trees the other day and said I could have the branches if I wanted. Many are 4+" in diameter with green needles on their smaller branches. I was thinking of building a hugel bed and was wondering how I should go about using them in it. I just finished digging a trench for the bed and have yet start to put the branches into them. Part of me thinks that maybe it would be best to let them dry and allow most of the needles fall prior. Stripping the needles will take some time and my avialable time is short right now for this project.

Anyone have any thoughts.

there's a lot of theories about the rot ability of pines because of the resin, but one obvious thing is i wouldn't spend too much time on stripping needles whether you choose to experiment with it or not

I buried some pine last year, jury is still out on how good it is, probably chipping them would speed their decomp, but burying is preferrable to burning-unless it's in a rocket stove.

All wood is good for some plant or another. Sometimes, often even, it is best for the tree it came from. I have been a ranger in Olympic and Redwood NP and western hemlock, red cedar, and redwoods all acidify and add tannic acids to soil that suppress microbial, fungal, insect and plant growth that are not symbiotic with their own growth. On the other hand, forests with these tree species have the highest biomass (organic matter living and dead/area) on earth, 5-10x that of tropical rainforests. They also have unrivaled soil diversity, as most of the energy in the forest is locked up in difficult to digest wood requiring specialization and there for speciation. We all want a great garden this year, but the longer decomposition takes, the more efficient it is. The temperate rainforests of the NW are the original hugelkultur plots and an abundance of food for large native human populations (largely acid loving berries, hazelnuts, tanoak acorns, salmon and elk) was a result. On the other hand, quick decomposition was encouraged by people who maintained prairie pastures for elk and understory plants like huckleberries and hazelnuts with low intensity fires (the old trees' 1ft thick bark protected them) and any seeds or trees remaining benefited from the fire's nutrients and likely basification of the soil. If this is what you are working with (acidic conifer wood, even spruce or doug fir is tannic), it would seem most logical plant those native trees on the north side of your property if possible as heat/wind breaks and restart the ultimate permaculture cycle, and generally grow acid tolerant plants with islands of less acidic soil. Given how one could simulate small fires with brush burning and ash scattering, the obvious missing link would be animals like elk, salmon and the distributors of salmons' nutrients (pretty much everything alive in a NW forest). This was a little bit rambling but my point is don't discount acidic wood, just think long term!

Hello. There seem to be many plants tolerant of walnut toxicity.
http://extension.psu.edu/plants/gardening/fact-sheets/trees-shrubs/landscaping-and-gardening-around-walnuts-and-other-juglone-producing-plants
I guess it would be ok to plant them on a bed that has walnut branches in it.
Does anyone have any experience?

I am so new to this but am an avid gardener. I am getting ready to add depth to all my raised beds so that I can add wood as an experiment to use less water each week. I need to know any feedback to using buckeye as my wood. I know that the fruit and flower is poisonous but want to know if the wood is toxic. Thank you for any replies.

denise broglio wrote:I am so new to this but am an avid gardener. I am getting ready to add depth to all my raised beds so that I can add wood as an experiment to use less water each week. I need to know any feedback to using buckeye as my wood. I know that the fruit and flower is poisonous but want to know if the wood is toxic. Thank you for any replies.

Welcome Denise. It rots quite readily. This usually means that the wood is not naturally poisoned. Also, grass and other plants grow beneath them.

I sure hope this is good wood. I dropped about 80 young cottonwoods today and cleared a large area.

we have a bunch of beds made of of different woody compositions ranging from hawthorne to river birch to dogwood to aspen and to cottonwood.

I have dug into the different beds to check out what the wood is doing and boy howdy was that informative. The cottonwood was by far the most spongiest-soggiest-delicousness. THis makes sense to the primitive fire specialist because they know that the highly porous nature of cottonwood (particularly the roots) makes it a good insulator for the coal generated by the contact of the spindle and fire board. Cottonwood trees can suck up gravel!!! Now it may bloody well be my imagination but i feel like the bed with the highest concentration of cottonwood kicks the most but on our project.

in the attached photo it is the mound on the left.

My cottonwood stores more water than the other more dense woods. My alder is by far the fastest rotter and the best supplier of nitrogen. I have cleared all other species from the perimeter of the gardens. Fresh leaf fall lands where needed.

How about ivy in a hugel bed?

A tree that came down in our garden was covered in the stuff.
That tree is already in the ground, but is there anything stopping me using the ivy in the next bed?

It's such a lot of bio mass, seems a shame not to use it.

Btw, it just common ivy not poisonous and apologies if this question came up before. I did have a look.

English ivy is extremely difficult to control and kill. Far worse than willow for me. I would leave it out. Any materials that may be contaminated should be set aside for a season, to ensure that it is dead.

I advertise for ivy eradication. $50,000 per acre. Nobody has taken me up on the offer yet, but I figure that's a safe bet for a serious infestation.

Wow. Im sure an acre of the stuff would be an impressive sight.

Its on maybe 8 trees here. Its not a very big place (sub 1 acre) so has been easy to get under control.

To follow-up Dave, if i let the ivy i have in a pile go brown and dry this summer, do you believe there is a chance the ivy could re-grow if i included it in a bed?

Dale here, not Dave . A whole year without signs of regrowth, should be sufficient. I would burn it, if it were mine. Even a light burning and quench might create some biochar.

Oops, sorry about that Dale. Thanks for the thoughts.

I buried these Douglas fir stumps, 18 years ago. It took 10 years for them to break down noticeably.

 The yard gets really dry in the summer, but this big mound  grows an abundant supply of brambles in the worst drought.

I have been very busy this year and didn't plant anything on this mound. Garlic and shallots have done well in the dry conditions. Here they are in the first week of June.

Just bought a farm with a little treeline containing a couple big black cherries. I'll have my garden on one side of the line and grazers on the other. They'll need to come down cause I don't want the toxic leaves in my pastures or my garden beds. Does anyone know if I can hugel with the wood? I don't think it will grow mushrooms, and I could save it for firewood if nothing else. Or can I...?

This may be a really stupid question, and I'm pretty sure I already know the answer to it, but I wanted to double check here.

My husband and I recently built a privacy fence around part of our yard for our dogs, and we have some left over pine (pickets, 2x4's and 4x4's).

I read earlier in this thread that pine works well for HK beds, but this is treated pine. Is that safe to use? If not, is there anything in the garden I can use the treated pine for? (Like a compost bin?)

I wouldn't use treated wood near anything edible. Your best bet may be to take it to the dump and never buy this sort of product again.

Para rubber trees (Hevea brasiliensis) are okay to use. These are common in Southeast Asia, and are said to originate in the state of Para, Brazil.

To begin springtime, Ive decided to take down two young pines in the middle of my hillside. Not so much for their unfriendly chemical tendencies, but because in the warmer weather they explode into fusiform gall rust - big orange spore gobs rupturing from the branches.

Since recovery is unlikely (the rust touches near the trunk), these guys are likely headed for less moldy pastures by spring.
Now, my question - would they be unwise to use in a hugelbed? I would probably sink them a foot deep and build at least 4 feet upwards with lots in between, but Im wondering if those spore ruffians would stick around and muss up the others? There are no other nearby pines so Im not worried about further contamination.

Hopefully this ancient (and awesome) thread is still alive!

Looks like their intermediate host is oak, so I wouldn't worry about burying them in a hugel, personally. The fungus should be quickly killed by earth-dwelling fungi.

Awesome, thanks! Ill let you know if I die.

Interesting comments. I posted this question in the urban thread, but didn't get much advice... I know ailanthus is bad, but HOW bad is it? Especially if it's not freshly cut? I have giant stumps in my front yard (a clump of 4 that are all 3-5 feet across) that are almost 3 years old. Can I make a hugelkultur over them with other wood, like ash? Can I use a few old-ish (also 2+ years old) ailanthus logs inside my hugels? Or am I really poisoning my garden if I do this?

Gum trees?

I'm out here in rural eastern Carolina (just south of Raleigh, NC) and started my first hugel bed the other day.

I'm not really sure if I'm doing it correctly, but considering what I have I think it's going to be "okay."

The wood layers on my hugel bed are sections of gum trees separated by a thick matting of pine needles and a layer of dirt. It's dug about two feet into the ground and about three feet above ground.

I topped it off with a thick matting of pine needles, a heavy layer of soil, and then one more heavy matting of pine needles.

Do you folks think that I'm going to have trouble like this? I gather that the pine needles will raise the hill's acidity, but am I missing anything here?

The only "spare" wood in my area is mesquite. I just cutbdiwn a bunch of them to make room for fruit trees.
Of course they are all sprouting now.
Could all this mesquite be used to make a mound?

I have a ton of hackberry trees that I could use for my new permaculture bed. I've done some research and could not find whether this would be good for that or not. I did find out that it rots fairly easily. The logs that I have are a year or so old end have already begun to dry anyone know anything about hackberry trees?

Hi, hugel fans! I'll be starting construction of my hugel beds in the next week or two and had a few questions before I dive in.

There are a number of big, woody plants that I'll be taking down around my property and replacing with food-producing trees. I'm wondering about their suitability for use in hugel beds.

Two big rhododendrons--any reason why their wood wouldn't be suitable?

A blue spruce and a Doug fir--I've read mixed opinions about conifer wood in hugel beds; I might just have to try it in one bed and see if it produces a noticeable difference.

And the big one I'm worried about: an English ivy plant that has fully matured/turned into an upright shrubby tree thing. It absolutely must come out, since its location really isn't working for me. I'm concerned about its use in the hugel bed, based on what Dale said above.

Does anybody have experience with fully mature English ivy wood in hugels? Danger, Will Robinson? Or does all the re-sprouting occur from roots and branch tips? If I only use the wood--no leaves, tips of branches, roots, etc.--would I be okay? Or would it be best to stack the wood somewhere and let it age for a year before using it?

I've got tons of dead, dried Himalayan blackberry cane I can use, which should be safe. Not going to put any crowns or green canes into the hugels, though.

I would not go against Dale on this stuff. Pretty similar climate, similar species. Buyer beware.

Tj Jefferson wrote:I would not go against Dale on this stuff. Pretty similar climate, similar species. Buyer beware.

I wasn't planning to! But he seems to be discussing the immature phase of English ivy, with the viney tendrils. I was just wondering if anybody has experience with the wood taken from its mature phase, which looks a lot like a laurel tree. It's got an upright trunk, branches, the whole shrubby nine yards!

I wouldn't use anything known to be seriously invasive, unless it is turned to charcoal. Large ivy can be used for firewood.
.......
I have been seriously neglecting the beds at my farm. I built more last summer, when more trees were brought down. Nothing was planted in the existing beds, since I got busy working at other things away from the property.  The current plan is to let them sit and rot a bit. The snakes and lizards do fine without me.

Meanwhile, they do make excellent garbage cans for the vast amounts of organic waste produced in maintaining roads and ditches.

Hey there I live in the Santa Cruz mountains. I'm looking to build out a lot of hugel beds this spring. I have redwood, pine, bay, oak, and madrone wood to use. I would like to use the redwood and pine to build the beds and fences.
I'm wondering what wood on my property I could use for the hugel? Oak? Seems like bay is way too oily and would be antifungal/bacterial as would the pine and redwood. I often see mushrooms around the madrone and oak. So I'm thinking those for inside the hugel beds maybe mixed with redwood/pine bark to keep the acidity down. We have a well on the property with pretty high pH hard water.

Any recommendations? I would like to put berries in some of them so maybe more acidic stuff in those?

Joseph I would reccommend to read the whole thread to understand fully. For example cedar is widely accepted as bad wood, but someone reported he had very good results with red huckleberry, gooseberry etc.
I was planning to make a different type of list, but decided not. There are some web pages attending the subject tcperma ; appropedia ; ourochre and more in permies. Meanwhile Jordan Lowery made a good point in that thread while they were discussing whether there is a real distinction, and I think it deserves to be mentioned at this post also:

"in my opinion it's all a matter of what you plant, and how long you willing to wait for decomposition to plant other things. there is no bad wood. I use cedar, juniper and pine for my gooseberry hugel beds. they LOVE that stuff, and will be 10x more productive than other woods. better flavour, bigger berries, higher yield. currants also do very well in them.
things that take a long time to rot are a different story, osage orange, black locust, etc... it's more of a waiting game at that point. but chances are you have more trees around than just those type of woods. and those woods are far better used in other ways."
So yeah it depends on your purpose. If you want your hugel bed to be productive a century after you built it (sarcastic smile here), osange orange might be the only good wood :) But a list doesn't hurt anyone.

But generally speaking:
1- Rotten or softer stuff (like alder, poplar) goes near the surface, while "maybe" or slower rotting stuff goes into the core of a hugelbed. You may include limited amount of allopathic wood deep in the core without any ill effect.
2-Trees suitable for pollarding might cause problems -sprouting. Maybe.
3- Using only a single type of wood, will cause the bed to have too much of a character. Poplar-hugels will rot fast (4-5 years) but will act like a giant sponge, while cedar-hugels will not rot initially (8-10 years min).  You might want to mix different types of woods to take the edge of.  
4-Introduced species may act like they are "bad wood", while they are "good guys" in their native range, and this cannot be blamed on the wood itself. Since the environment lacks specialized decomposers (especially fungi) adopted to deal with tannins, oils and allopathic compounds, decomposing process may linger, and these compounds will have a negative impact on hugels. (While I was raking through the web, I came across numerous conflicting feedbacks on some species - eucalyptus, pines, oaks and somewhat bamboo. When I dig in, I realized that there is a overlap with native-introduced range with this problem. This is expressed also in one of the comments in one hugelkultur article at permulturenews.com. Unfortunately, it introduces subjectivity to the list, so I neglected negative feedbacks from introduced ranges.  House-plants and other exotic plants might decompose slower as well).
5- There are many uses for "bad woods". They are sought after for their rot resistance and dense wood properties.  They might have a higher purpose.
6- You might want to exclude diseased wood if you don't know how contagious it is (especially from monoculture production areas - olive). Some diseases, such as fire blight, might escape.  Meanwhile you should not forget that burying is probably the oldest way to get rid of all kinds of nasty stuff, so similarly hugel beds will effectively lock and kill slowly most diseases (of plants). Only 5% or maybe even less of diseases might be an issue. Burying deeper or other techniques (biochar) might be solutions.
7- I couldn't find it where I saw it, but someone claimed that spring cut trees with all that water and energy stored and being programmed to leaf out, are more prone sprouting, while winter cut trees lack water, so they struggle to sprout. Currently I am experimenting something similar with poplar and pale: spring cut poplar and pale is sprouting like crazy, winter cut not so much. So, I think it is a valid point, but I wouldn't rely on.
8- There are thousands of species of trees out there. The list doesn't include all of them.  Observe the nature, search the web if you know the name, or just do it and report back your results :).

Here is a short list of good wood/bad wood.
Good wood:
-birch
-alder (fast rotter)
-milkweth (arttic)
-cottonwood (acts like a giant sponge)
-willow (a 1000% dead willow is good, 99% not so much... Willow is well known to sprout as it is a zombie plant, extreme caution here!)
-mulberry (might sprout)
-sycamore
-maple
-douglas fir (or you can use it for construction)
-poplar (acts like a giant sponge, fast rotter)
-apple
-juniper (some reported very favourable results)
-fir
-plane (might sprout)
-oaks (perfect for hugels, but you can also grow shitake mushrooms)
-pine (there is a general discussion about this, depends on the species, where you are located and your purpose me thinks.)
-spruce
-aspen
-ash
-cherry (not black cherry)
-buckeye
-green snake wood (condalia viridis)
-buckthorn (maybe)
-Palm (outer trunk might resist to rot. There are positive reports from florida)
-para rubber tree
-bamboo

Bad wood:
-cedar (rot resistant. Second growth or fast growth are less rot resistant. Some had good results with cedar, with red huckleberry, gooseberry)
-black walnut (emits an allopath called hydrojuglore (??), wood is valuable and south after, blackberry and wild grape is immune to its allopathic character)
-black locust
-ailanthus or tree of heaven (allopathic)
-arizona cypress
-redwood
-sequoia
-california pepper tree (allopathic)
-osange orange (takes ages to rot)
-black cherry (emits a allopath called amygdaline (??), wood is valuable and south after)
-china berry tree
-catalpa tree (?)
-fuchsial (sprouts very strongly)
-himalaya berry (don't use it when green, it will definitely sprout, good when dead. Or goats love it)
-salmon berry (will sprout)
-english ivy (zombie plant)
-mesquite (has a higher purpose, very dense wood, perfect for fuel wood)
-olive (olive has allopathic properties. I used it in one of my hugels, and it didn't perform very well for over two years. Maybe its allopathic character dies of in a year or two. Also most olive trees are treated with -cides. Caution!)

Again, there is no bad wood, only better uses for some woods than hugelkultur.

I find it pointless to generalise to such an extent. The only hard-and-fast guideline (Not even a rule) is that allelopathic trees and plants require special attention. This, I think, makes them excellent candidates for biochar.

I  also wonder if compost extract would have a positive effect on normally resistant material, and if including the wood duff of the allelopathic species in the compost extract would increase the populations of soil life in the extract most likely to quickly decompose said allelopathic material.

I think that fungal resistance of some woods might be of great value in a hugelbeet designed to act structurally on the land, where the buried fungal resistant wood, like black locust, say, is required to keep the form of the hugelbeet over time, until perennial woody species knit the pile together.

I would submit that a hugelbeet parked on contour of a 45 degree slope with a row of tall-cut black locusts stumps as rooted anchors, their cut trunks and biomass forming the downhill wall, and planted for terrace retention, would far outperform virtually any hugelterrace design made of more quickly decomposing materials in the same situation.

So as with anything in permaculture, the application is usually good or bad, not the materials. If all you have is pine, deal with it. Use the pine, brew a pine-based compost extract, plant buckwheat, blueberries, raspberries, and potatoes, and don't bank on alkaline plants doing well in acidic conditions. Find out what expensive and tasty culinary mushrooms grow with the wood you're trying to use, and maybe you'll find yourself using pine on purpose.

One of my favourite hugelbeet ideas is to make a giant pine-based hugelbeet on the windward side of my property, as a shelter belt. I want to inoculate the whole thing with chanterelle spore, and do exactly what I stated above regarding a polyculture of acid-loving berries and food plants.

I think it's much more useful to overcomplicate than oversimplify. Robust systems tend to complicate themselves, becoming more intricate, rather than simplifying and becoming more straightforward.  Detail is the path to resilience, whereas systems requiring a binary breakdown, in my opinion, will keep simplifying themselves to the simplest state of all.

-CK

Here in Central California I live at the edge of the oak grass woodland and timber line of the Sierra Nevadas.  Over the past 5-6 years the drought combined with bark beetles and other tree killers has created an excess of mortality trees from the 1000’ elevation up to the 8000+ elevation; oaks and conifers alike.  Wood is free for the taking; millions of acres from Sacramento to Bakersfield and the beetles are marching, or munching their way further North all the way to the Oregon border.
I’m wondering what trees I should use for hulgukulture? Ponderosa pine, sugar pine, white fir, blue oak, live oak? Free chipped trees too.
Any suggestions?

I have hugled' tons of black walnut with no Ill effects. From 10 foot raised beds, to complete dozer piles of black walnut covered in dirt.  Seems to grow just fine.

How about filling bottom of trench with diseased wood? I have marshmallow fungal wood...is this safe?