Hugelkultur -- good wood, bad (allelopathic) wood

When it comes to spruce, fir and pine - all of these will work fine. They won't work as well as cottonwood or poplar, but most hugelkultur beds I've heard of are using spruce fir or pine. Check out this video where Mark is using spruce - looks like it is working pretty damn good



Locust, cedar and osage orange are out. They have too much anti-rot stuff.

Willow (and a few others) can shoot up suckers and you can have instant willow tree popping up out of your hugelkultur. So you wanna either be okay with the new tree, or you wanna mitigate that problem (mulching, burying deeper, or snipping off the sprouts).

I am curious about stuff like black walnut or cherry. I suspect that they will be fine cuz their ick while they are alive is probably not happening while they are rotting away. I kinda check into this thread once in a while in hopes that somebody will have done the research and will post the final results here.

When in doubt, I would just mix iffy wood with known good wood. If the iffy wood doesn't break down, it would be like having a big rock in there. If the iffy wood puts out some sort of natural herbicide, the plants will avoid it - favoring the good rotty stuff. For most natural herbicides, there is something that can tolerate it.

I would use aspen in hugelkultur. I don't know of any problem with it. And there is nothing that I currently know about it that gives me the willies. In fact, I think it would be better than most for hugelkultur.

If anybody knows of anything about aspen on why it shouldn't be used, I am excited to hear about it.

As for "good vs. bad": I do think there is a spectrum of better-tude and it is wise to build knowledge in this space. It would be cool to someday have a big grid that shows trees down the left side and uses across the top and the grid shows a number in what it would be good for. And one column could be "value inside hugelkultur" and another could be "value as an edge on a raised bed"

Thank you Paul. I will forge on! I will be adding dropped black walnut branches and holly tree branches to another hugelkultur. I'll post as it comes along. Thank you again for your response.

paul wheaton wrote: It would be cool to someday have a big grid that shows trees down the left side and uses across the top and the grid shows a number in what it would be good for. And one column could be "value inside hugelkultur" and another could be "value as an edge on a raised bed"

I've seen tables that deal with rate of decay on the forest floor. There should be some correlation between the tendancy to decay quickly and lack of aleopathic properties which would indicate suitability for hugelkultur.

Aspen is quick to rot. Aspen forests have plenty of undergrowth wherever there is enough light, which would indicate that it isn't poisoning the soil.

there's a huge black walnut tree on a farm i'm sharing that will be trimmed in the near future, and i want to use the wood for a hugelbed. i've seen comments here that black walnut is a no-no for hugelkultur, but has anyone actually used black walnut in a hugelbed, and was there a problem? thanks!

eric firpo wrote:there's a huge black walnut tree on a farm i'm sharing that will be trimmed in the near future, and i want to use the wood for a hugelbed. i've seen comments here that black walnut is a no-no for hugelkultur, but has anyone actually used black walnut in a hugelbed, and was there a problem? thanks!

Black walnut is one of the most sought after woods for lathe work and other fine woodworking. Even stuff only 4 inches in diameter is used. Beter to carefully dry this wood and market it. The world is filled with low grade wood and anywhere that grows walnut will have many other wood waste resources. I've seen prices starting at $5 per board foot. Burls and crotches can go as high as $25.

When I was 18, I cut up a huge walnut for firewood. Two years later, I did the same with a clear hickory log almost 4 ft in diameter. Not too bright

Dear All,

Great thread. I was out a my coder's house and he has just fell a bunch of Ponderosa Pine.

Paul stated pine would be fine, does that include Ponderosa, maybe a dumb question, but this is alot of work and I don't want to screw it up from the get go.

Cheers!

kt

Oh super! I have tons of dead birch trees on my property. But I guess that means I have lots of wood for hugelkultur mounds.

Also, I have a hillside with a pile of field stones. I used to look at these unsightly piles as a bother but this year I'm going to try putting a wee bit of composts and soil over the rock piles and make a cucumber/squash garden. Hope I can keep the deer off them though.

Do you think the rock pile/squash garden idea will work? Any other suggestions. This hillside is south- west facing and is dry as hell.

Paul Wheaton wrote:I am curious about stuff like black walnut or cherry. I suspect that they will be fine cuz their ick while they are alive is probably not happening while they are rotting away.

I Googled it and found this helpful page from North Carolina State University (and this one). It says that hydrojuglone, the allelopath that black walnut emits, "is found in leaves, stems, fruit hulls, inner bark and roots." It sounds like the sapwood and heartwood doesn't contain it though, so maybe if you strip the logs of bark and don't throw in any leaves, twigs, or roots you would be in the clear.

Some plants are tolerant of hydrojuglone while others are sensitive to it, so if you include the allelopathic parts (or maybe even if you don't, just to be safe) you should plan your hugelkutur accordingly. Black raspberry and wild grape will presumably grow without a problem, but you won't have a prayer if you try to plant tomatoes, potatoes, or blueberry.

You were wondering about black cherry as well... I was able to find that it emits an allelopath called amygdalin, but I couldn't find any handy lists of plants that are tolerant/sensitive to it or any webpages that describe amygdalin's properties. I'm curious to learn more about it though!

But like Dale said, if you have black walnut wood you probably shouldn't use it in a hugelkutur anyways. The same goes for black cherry! Both of those woods are valuable and sought after. It's kind of a waste to burn or compost them unless you really have no other wood available.


I think allelopathy is important for permaculturalists to learn about because so many trees seem to be allelopathic--but does anyone know of other plants that might be allelopathic?

I would say china berry trees would be a no no, plus lots of wood ashes from something like pine trees.

This is one of my larger beds at about 500 sq ft. I think I have about 2000 sq. ft. in all. It looks like most of the trees aren't going to sprout roots as I had feared. Most of the wood is cottonwood, alder and maple. These beds will be left to nature for 2 years. Various soil amendments will be added as time and resources allow. Sea weed is abundant as are coffee grounds that I pick up in big sloppy bags. I often inherit compost heaps at demolition sites.

My tennants may plant some or all of that area but my time and financial priorities lie elsewhere for now. I figure that there's no point struggling with wood that has barely begun to break down. When I am ready to plant, nitrogen shortage and poor workability will have been partially dealt with in my absence.

If there is a line between hugelkultur and slash piles, my efforts lie clearly on the wrong side of this line. But when you consider that these beds are produced at about 200 sq. ft. per hour (my cutting time, the excavator piled it all) it has been a very efficient process. By the time I get to planting, I may have 5 or 10 thousand sq. ft. of beds. Some of the required wood will come from my own property but much of it will be stuff that I or my tennants are paid to dispose of. Long before I pick my first carrot, these beds should produce several thousand dollars in dumpage fees. In this way the hugel beds will be my number one "cash crop" for the first several years of this new farming enterprise.

I'm shopping for a small mill that will be used to process hardwood logs. The sawdust and scraps will feed the hugel beds. I'll mill my own wood and will mill for others on a 50/50 basis. Mill scraps contain a disproportionate quantity of nutrient rich bark as compared to complete logs.

At least once a week, I re-examine the various ways that I might get others to pay me to take away resources that I need.

i made the mistake several years ago putting jerusalem artichokes in my smallish 40 x 45 garden, and they escaped..so I have spent all spring digging them out of the beds, and yes I'm waiting for every single stray to sprout before I rebuild the beds..

so..once they are clear of sprouts, I'm hoping to rebuild them hugelkulture, but they won't be super tall as some have some dwarf fruit trees in them..but I have several choices of wood and am attempting to decide which would be the best of the woods for the beds..

I have some very old aspen, which is disintegrating, it was piled for campfire wood and never used..

I have some dead and some alive alder
I have dead and alive ...some old and some new cut aspen
I have dead and alive ..some old and some new cut ash

I also have bark which I have used before in hugel beds..

IF YOU were doing yours, which would you choose?

I think there are two main criteria here. It comes down to highest and best use.

1. Which raw materials would be the most suitable for hugelkultur. This should include things like nutrient balance, water holding capacity and longevity if you care about that one. The alder would add lots of needed nitrogen. The bark of all of these woods contains more nutrient than the heartwood and it breaks up to form a growing medium in less time.

2. Which materials are good for other things. Ash makes good firewood. Most aspen and alder have few uses but both can produce some good specimens. Both make low grade firewood and lumber. Both are prone to rot although aspen is more durable. Bark makes a great mulch for row crops. If not needed for that or to provide paths in muddy areas it makes sense to dispose of it in the beds.

I think that every wood you've mentioned is suitable. I wouldn't put any large, useful ash in the ground. Everything else you've mentioned is stuff that often needs disposal. Hugelkultur is the perfect way to dispose of unwanted woody materials.
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Fencing pigs on the artichokes would be more effective than you sifting through it a dozen times.

Dale everything you just said makes complete sense to me, but can't have the pigs here (can't afford the fencing)..I'm planning on useing the crappiest of the aspen and alder in the hugelbeds and saving the better wood for firewood..just as you said..i wasn't sure if putting some of the better would in the hugel beds wouldn't be a better idea but what you said here makes more sense to me..thanks.

Brenda Groth wrote:Dale everything you just said makes complete sense to me

Editing can be fun!!! That's what every man wants to hear no matter what comes out of his mouth.

I recall that there is a network of trails leading to neighboring properties and that a certain species of tree has suffered from bugs or disease or both in your area. You may have neighbors who have lots of rotty stuff to give away.

i have an abundance of ROTTY stuff here ...just a matter of choosing the best rotty stuff to put in the beds..the be.ds aren't that large so I just wanted to make sure I used the best of the stuff I had on hand

Yesterday I was still pulling a few JA's out of the beds, about a half dozen..hopefully there aren't too more hiding in there so I can get busy rebuilding them soon

Anyone have experience with composting wood/branches from Catalpa trees? I find information on the internet stating it has alleopathic properties.

I'm interested in using some fallen branches for hugelkultur beds.

Even if certain species are considered "alleopathic" are they always going to pose a problem for hugelkultur beds, or only take longer to break down/decay?

Bryan Milne wrote:

Even if certain species are considered "alleopathic" are they always going to pose a problem for hugelkultur beds, or only take longer to break down/decay?

My personal belief is they will not pose a problem. So far I have not experienced problems with Juniper. I would personally have no hesitation with using Catalpa.

I've come up with a few more items to add to my own criteria for good wood.

Does the wood support the growth of Shitake mushrooms and other marketable fungi ? --- I've started a new thread based on the idea of inoculating log ends in a hugelkultur bed with desirable species so that they may help with decomposition while adding value to the crop.

Does the wood inhibit fungi production ? --- Some do.

Does the wood tend to promote the production of undesirable fungi ? --- Some do, but that wood could still be incorporated deep in the hugel bed with only the suitable mushroom substrate exposed. --- Shitake does well on Oak, fruit woods, alder and other hardwoods. Fir and pine could still be used as water sponge and nutrient trap at the very deepest areas.

Does the wood impart a negative taste to the mushrooms ? --- Apparently some do and the prices of mushrooms on the gourmet market change according to the type of wood used.

So, for beds that will include mushroom production, the best quality hardwoods will be reserved for the upper area of the bed while lower quality woods need to go on the bottom. As luck would have it, those hardwoods contain more nutrients for the garden than the same quantity of coniferous wood.

With all of the conifers on the bottom, they will last a long time as both water and nutrient sponges so this is probably the best way to go, even if the bed were not going to grow mushrooms.

I live in Florida and have a couple of acres of land with beautiful secular oaks on it, along with a variety of other subtropical trees and shrubs. There are a lot of piled up
and decomposed twigs and leaves from former owner's yard work as well as a heap of larger branches in piles left from tree trimming. I have a question! Can I utilize all of it
for my Hugelkultur? Or is oak bad?

Oak is perfect in my opinion. I use lots of oak.

Tyler Ludens wrote:Oak is perfect in my opinion. I use lots of oak.

Oak is also the preferred food for shiitake mushrooms and other valuable fungi. I'd happily trade all of my softwood for oak.

I have done a bit of research to answer some of my own questions regarding allelopathy and this seems like a good spot to share my observations. First I must say that it seems like allelopathy is not a very studied phenomenon and there isn't that much info out there, especially research or studies. Most of the scientific stuff I could find was in regards to black walnut which is pretty much common knowledge. I did manage to find one good study online that had a pretty large list of trees with their degree of allelopathy and which parts of the tree contain those compounds. The general trend I observed is that allelopathic compounds are mainly present in roots and needles/leaves. This makes a lot of sense to me as those two vectors would be the most effective routes to spread growth-inhibiting compounds into the soil around a tree......logically it just doesn't make sense for a tree to create these compounds and then store them in the trunk or main branches since they wouldn't affect the soil until the tree falls over dead. So my basic assumption here is that the wood itself should be safe to use on most trees considered allelopathic.. It is the limbs with needles that I find suspect and have been avoiding.

One aspect of allelopathy that I couldn't find any info on is the amount of time it takes for allelopathic compounds to break down. If anyone has any insight into this or my above comments, than please share!

So I have a ton of wood that I have split and even more yet to be split for burning how ever I don't have room for it anymore. I recently found out about HK and got excited as my wife loves to garden! We already have nice landscaped raised beds but I'm thinking of digging them out and putting some of my non split wood in there. I have some 2 year seasoned maple and will be getting some fresh birch and pine in the new year. Will all of these work? I know I've seen people talk about the maple and birch but not much mention of the pine. Anyone using pine? I'm worried it may be toxic on very acidic but I don't really know. Any insight would be great. Thanks everyone! I'm really enjoying this forum and learning about all these new things!

Apparently I missed this post altogether lol Thanks for answering my Question 8 months ago lol

paul wheaton wrote:When it comes to spruce, fir and pine - all of these will work fine. They won't work as well as cottonwood or poplar, but most hugelkultur beds I've heard of are using spruce fir or pine. Check out this video where Mark is using spruce - looks like it is working pretty damn good

In searching out poisonous woods, I learned that yew is quite valuable for bow making, bowl turning etc. I had heard this but wasn't really sure what it looked like. It turns out that I've removed them for customers and dropped stuff up to 8 inches in diameter at the wood dump. From now on I'll save it. Check out the many faces of yew on google images.

Oops --- Double post. I tried to link to google images but the link made the page three feet wide. Let's try this one instead. http://www.healing-arts.org/edric/englishyewrootvase.htm

Has anyone tried Arbor Vitae (sp)? I cut down a bunch of it last summer and would love to put it to use in a hugel-k. My backup plan would be to chip it and use as a mulch.

I plan on dumping tons of coffee grounds into whatever I use to add some good nitro.

I'm starting some blueberry plants so acid soil is desired.

I also have a nice source of free woodchips that I want to try to use in my Hk veggie garden. They will breakdown fast but being that I like digging in the dirt, I won't mind redoing the new bed in a few years.

Thanks for any info,
Corey

I like what I hear about poplar's all-round, middle of the road qualities in a hugelbed AND it's super sponge attribute. Am I right to treat it similarly to willow in it's rooting ability and to take similar precautions? BTW, my first post here. Awesome site!!!

I put quite a bit of poplar in a wet spot without sprouting problems. Willow twigs that blow off a truck will root in a pothole along the road.

Thanks Dale. Nice to hear your perspective, and good timing, too. Will load up (deep) the hugel with poplar now, run some sprouting experiments in the future.

FYI: Thought this correction to my post was funny, "The specific error message is: [deleted] is a silly English abbreviation; use "thanks" instead."

Yikes, I piled mostly maple branches with some other fresh prunings 3 feet high, 6 feet wide and 50 feet long to make a berm to deflect road noise away from my house a bit and create privacy in the future in my front yard living space off my house from the road with the eventual landscape mix of ornamentals and food plantings . I am leaving this uncovered through spring until drier weather to facilitate the branches dying before I attempt to cover them and not regrowing . Now I wondering how long I should leave it exposed to sunlight and air before covering to ensure it does not grow ? My yard looks like a beaver built a dam in front of it .

Lisa Paulson wrote:Yikes, I piled mostly maple branches with some other fresh prunings 3 feet high, 6 feet wide and 50 feet long to make a berm to deflect road noise away from my house a bit and create privacy in the future in my front yard living space off my house from the road with the eventual landscape mix of ornamentals and food plantings . I am leaving this uncovered through spring until drier weather to facilitate the branches dying before I attempt to cover them and not regrowing . Now I wondering how long I should leave it exposed to sunlight and air before covering to ensure it does not grow ? My yard looks like a beaver built a dam in front of it .

Although it is tough to kill maple roots that are undisturbed, cut branches don't usually root. I have cut the same bushy growth from an established stump several times, but none of the trimmings took root. Maple cut 2 feet above ground level provides easy harvest coppice and good animal forage.

Thanks Dale, I am going to be able to leave them out in the sunshine a few more weeks before I begin covering them over with stable muck . There are all sorts of prunings, even blackberry but that has been cut for a while , nibbled on by rabbits and added to the berm when it is looking pretty withered . First year I am only going to have a few strategically planted hedging plants going on it plus I will grow squash and pumpkin all over to help keep down the weeds .

Good to know about the maple as I am intending to plant some intentionally in my perimeter shelterbelt for pollarding fuel for a woodstove. You know the old saying about the road to hell being paved by good intentions ...

Lisa Paulson wrote:

Good to know about the maple as I am intending to plant some intentionally in my perimeter shelterbelt for pollarding fuel for a woodstove. You know the old saying about the road to hell being paved by good intentions ...

Consider some red alder in the shelter belt since it's our best nitrogen fixer(along with broom) and provides forage. Goats will nibble most of the bark off small logs. The wood dries fast when debarked.

Dale I googled red alder, is it the regular alder we see growing here native in our BC coast ? If so I have one baby alder tree in my "nursery" for transplanting into the hedgerow in due time. I am planting a lot of variety into it but I do have only 4 acres total and have to optimize it as I have a lot on the go in 4 acres : )

I have just started adding stable waste from the barn to cover the wooden branches in the berm 50 feet long, 6 feet wide and 3 feet high before this addition . It will take months yet.

So is generally any wood that coppices well that has a good chance of sprouting from cut branches? I'm taking down a Manitoba Maple growing on the south end of my tiny backyard lot, and planning to make hugelkultur out of it. I've used its cousin in last year's hugelbeet, with no ill effects as yet, although those pieces had been sitting out on the ground for a year before that. I'm guessing that, as with other types of maple (I think the Manitoba Maple is also known as boxwood elder), while the root systems are very resilient to damage, the cut branches won't root like willow.

I think that one has to keep in mind, as you've mentioned, Dale, that different people use hugelbeets differently. If I was building a bunch on contour, I think I'd probably either grow saplings of Black Locust or Cedar, or some other tree species that doesn't break down quickly, on the site where the bed will be, then slash the tops to a few feet below the estimated top of the finished bed, and incorporate the saplings, still held in the earth by their roots, into the hugelbeet. Unless I have overlooked some crucial detail, the saplings would act as vertical bracing tied by the root systems to the earth. Other slower-rotting species could be selected for structurally strategic placement within the bed, even to the point of interweaving with the vertical rooted saplings, and of course as walls to the raised beds, not something Sepp does, but I'd give it a go. I'm using pallets from work to make 3' tall container walls with 6'' buried, making for vertical sides, at least for the bottom few feet.

Otherwise, I have to side with Dale on the issue of some types of wood being inappropriate for hugelkultur, not because of anything they do badly within hugelkultur, but because those least appropriate for hugelkultur usually have much better uses.

-CK

Neal Styka wrote:I was considering making a hugelkutur bed with some mulberry limbs and branches I cut down when I pollarded the tree earlier this winter but had someone suggest that perhaps Mulberry like willow might sprout and then root. Any thoughts on if this is likely or not?

Very likely to root, at least in the tropics I stick twigs in the ground and they grow. Great for high protein feed and berries
, bad for Hugel beds.

Lisa Paulson wrote:Dale I googled red alder, is it the regular alder we see growing here native in our BC coast ? If so I have one baby alder tree in my "nursery" for transplanting into the hedgerow in due time. I am planting a lot of variety into it but I do have only 4 acres total and have to optimize it as I have a lot on the go in 4 acres : )

I have just started adding stable waste from the barn to cover the wooden branches in the berm 50 feet long, 6 feet wide and 3 feet high before this addition . It will take months yet.

Yes, red alder can be found in almost every damp area of BC. It's our only large nitrogen fixer. Since we get very little lightning(fixes nitrogen) it's important to grow alder, clover, broom or other sources.