Lucian Holland

Hi All,

We recently moved to an off-grid finca in Spain and have started composting all our humanure. We're doing it more or less according to the handbook - a bucket-and-chuck-it system with two big compost enclosures (~2.5m3). We're putting our kitchen scraps and our humanure into the middle of the pile, and covering with dry strimmings from our land. We throw on whatever water we use to clean the buckets each time, and at the moment we're keeping the whole lot covered with black plastic to prevent it drying out in the heat here. We've filled about 1/3rd of the first pile so far. The core of it is getting to just over 50C in the middle of the day (slightly cooler at night) at the moment. It also has quite a thriving community of wriggling larvae when we peel back the top layer. I'm not sure if they're BSFL (hoping they are!).

We're now just finishing off building a chicken house + run nearby, and I was wondering about whether we can connect these two things up in some way. The chickens would obviously love to get at the larvae, and it would hopefully reduce the amount we needed to feed them, but I don't really like the idea of letting them at the pile itself - partly because, by the book, we're not supposed to be turning it, and partly because it sounds like a recipe for spreading undesirable microbes all over the place (including our eggs!). On the other hand, I know that there are people who swear by letting their chickens at their regular compost piles - turning and shredding and adding lots of chicken poop - so I thought I'd ask if anyone has any thoughts on the matter. I guess at worst we could fish out some of the larvae as a treat for the chooks occasionally...

Cheers,

William Bronson wrote:How about hoop houses or low tunnels?

<Slaps head> Of course. We even saw some people with polytunnels made this way on the other side of the hill a few months ago. We'll definitely keep them for that!

Thanks!

We've inherited a big pile of used irrigation pipe from the previous owner of our smallholding. We've used some of it in fixing up the existing drip irrigation system (which we'd rather get rid of entirely, but that's another story!), but the majority of it is just too tatty to be worth reusing for its original purpose - too many splits, holes, kinks etc. I doubt that there's anywhere round here that we can take it to be recycled (to be honest I strongly suspect most of the "recycling" here goes in landfill anyway), so I was wondering if anyone has any creative suggestions for alternative uses that it can be put to. It's mainly 20mm diameter stuff, with a few lengths of 25mm and 32mm. It's too big/inflexible to be used as ties for things.

Jack Edmondson wrote:Lucian,

I have not tried this plant, yet; although it is on my spring planting list to experiement.  http://petcherseeds.com/pigeon-pea/  According to this source, pigeon pea will make a crop on as little as 30cm of rain, once established.  If anything can make it through your summer, this would be it.  It has a deep taproot and is a legume.  Again, I can't yet personally attest to it efficacy; but may be worth more research for your situation.

Excellent - thanks for the tip. We may also be able to get away with other cover crops like alfalfa - we're not a desert and we do have *some* irrigation water - but it's good to have lots of options!

We've also got to work out how to sow whatever we're going to plant into our compacted soil so that it can compete with the grasses. Normally I'd be thinking of sheet mulching to knock back the grasses and then planting into a new layer of organic matter over the top of the existing soil, but on both counts I'm a bit worried about suffocating the tree roots/preventing water from penetrating to them.

Jack Edmondson wrote:Plant lots of cover crop with deep roots.  Let the plants do what they do, deep till and scavenge for nutrients and moisture.  Popular plants are comfrey, turnips, alfalfa, hemp, bluestem, etc...  Any root mass will combat the cattle compaction on the surface; but there are many plants that will drive deep roots through hard pan to start the process of opening up the sub soil.  I agree that you don't want to damage the tree roots.  However, a "once to get started" deep aeration may be in order.  Get familiar with how a subsoiler works.  It opens up a single channel, deep, but does not overturn the soil.  Make a determination on where the root mass is primarily concentrated and sub soil between the rows in the safe zone.  At least then you will have some aeration to the microbes in the orchard to start the process of decompaction.  The manure, if free from chemicals from the feed, will do a lot over the roots where a subsoiler is unadvised.  Wood chips would be better; but I imagine in short supply in your area.

This was the answer I was kind of expecting - the thing I'm worried about is whether we're going to be able to keep those sort of plants alive effectively through the summer with the water we have. I've seen comfrey die in the summer here on other people's farms. Are there plants that are good for breaking up soil that are good in dry climates? We're above the snow line so we can't grow through the winter like many places here in Andalucia, so there's a relatively short window where temperatures are clement AND water is readily available...

Your points about the clay pan are certainly food for thought. There are people with subsoilers that we could borrow/rent here, but even if there wasn't the risk of it being a bad idea to break the clay pan, the trees are planted in a fairly "random" fashion, not in rows, so some root damage is almost inevitable.

Overall it seems like getting as much organic matter + some deep-rooted plants that are drought tolerant is probably the way to go, rather than trying to plough stuff up.

Also, Tyler, yes, we're intending to put in some swales to improve water retention. The terraces are *reasonably* flat already, which helps.

Hey all,

We've just moved to a smallholding in the mountains of southern Spain and are trying to work out what we can do with the land we have. One problem in particular has us a bit stumped.

There are a few open patches of land that we're thinking of using for growing vegetables, but a lot of our terraces are planted with fruit and nut trees - primarily chestnuts and walnuts, with a few olives and a smattering of other fruits (mulberry, pear, cherry, plum, fig). The primary trees range from maybe 15-30 years old; in most places they don't form a closed canopy at the moment. At the moment the ground cover, such as it is, is just wild grasses and flowers.

We don't have a lot of water at the moment, partly due to a series of dry winters, and partly due to local water politics. The trees have been drip irrigated for quite some time as far as we can tell - probably not particularly generously. The soil underneath the trees has been heavily compacted by (unauthorised) cattle grazing by the local herdsman, and in while digging post holes the other day I observed that there's a marked clay pan 20-30cm below the surface. The pan is probably only 15-20cm thick.

We'd like to plant under/between the trees to a greater extent, partly to be able to plant beneficial plants for the trees, partly to improve water retention, and partly to make better use of the space. However we're not sure what to do about the clay pan. A lot of olive farmers round here plough between their trees aggressively every few years, but I'm really nervous about doing this even once - I'm worried about damaging the root systems of the trees, particularly since they've been drip  irrigated and may have higher roots than normal. On the other hand, if we're going to improve things here I think we're going to need to break the soil up somehow, both for the long term healthy of the trees, and to make it possible to plant things underneath. Plus we need to start storing a lot more water in the soil,  which I think means breaking through that clay pan to stop it all just pooling on the surface when it does rain.

We have access to a large supply of (mainly unrotted) horse manure (riding stable just down the road), and we're also making a certain amount of mulch from prunings of dead wood using our chipper, but neither source is anywhere enough to systematically mulch the whole area to a useful depth (we're probably talking about 3000m2). Solutions that will require us to irrigate substantially during the 6 months or so when it doesn't really rain here aren't going to be viable for the time being either. We're planning to invest heavily in more water storage here but even so it's probably never going to be enough to water all the trees as much as we'd like.

What would people suggest here? Should we be looking at a mechanical approach to breaking things up? Is there a plant-based solution that wouldn't require huge amounts of water?

Cheers,

John Pollard wrote:Waiting for the scientific community to make up their mind and agree on something. In the end, it's whoever has the best funding and political/business connections that wins the argument publicly.

Yeah, I'm not really talking about waiting for the scientific community to pronounce on compost toilets, that's likely to be a long wait. But I'm guessing that the basic biochemistry of urine decomposition and it's relationship to bio-available nitrogen in compost/soil may well already be quite well understood, and I figure that's a good place to start in making decisions about this stuff. If the knowledge is already out there it makes sense to use it..

John Pollard wrote:
I think the "permaculture spirit" is more like, if it already happens in nature, then it's probably ok.

Agreed. The tricky bit is identifying what "happens in nature". It involves a whole lot of assumptions about what is "natural" and also a lot of presumptions about our ability to identify the salient features of natural systems when trying to replicate them (because we never replicate them completely). That's where the skill in observation comes in. We can get over-confident about our abilities to take apart natural systems and understand how they work (that's Fukuoka's whole gripe, as I read it); but equally if we go too far the other way, we deny ourselves the tools to make meaningful observations, because we can't distinguish what is relevant information from what isn't. My preference is probably further over to the analytic end of the spectrum than most, but I recognise that it's a balance.

John Pollard wrote:
And that was probably no help at all.

Not at all, it's always good to hear other people's experiences and perspectives. It may not be the way I'd approach it but it's still a data point!

John Elliott wrote:Here's a thought on how you can keep the nitrogen from leaching while making it less offensive to handle -- chelate it.

Wow - that's a really fascinating idea. I'd love to give that a go at some point. I'm wondering what else one might use to absorb the urine in ways that might help fix it more permanently. I know that people make simple urinals out of straw bales, which seems to be closely related to the role of sawdust/shavings/peat moss/etc in the traditional humanure system. If one takes fresh urine (before it starts to break down into ammonium etc) and soaks it into carbon-rich organic matter, what happens? Is the chemistry of that process any more conducive to the nutrients not being leached out than storing the urine and applying to the soil later?

Sorry, that's a lot of questions! I guess the permaculture spirit tends to be more "give it a go and see if it works", but I'm concerned that it would be very easy for it to seem like it was working great, but was actually setting up hidden problems for the future because I just wasn't observing all the outputs accurately. I guess that's kind of how we got ourselves into the mess we're in today with soil fertility in the first place!

Hello!

We're currently in the process of planning a new permaculture-ey life and are doing a lot of the thinking about the practicalities. One of the these is obviously composting toilets; over the last year of travelling we've used a lot of different types, and picked up a fair few ideas about how we'd like to make it work for us.

Now I know that people are divided on the benefits of urine-diverting toilets, and obviously a lot of it comes down to what you can make work effectively for you - it's clear people have had success with both approaches. But one thing we really noticed is that if handled badly, the urine is *by far* the nastiest bit of the process (whether separated or not). Emptying a bucket of urine that has sat open in the sun for two days is one of the most retch-inducing things I've done in a long time. On the other hand, for an indoor bucket toilet, separating out the urine really cuts down on the emptying, and an "unseparated" bucket where the urine has gone ammonia-ey can be even nastier than the stale urine on its own.

But the thing that worries me most is that there seems to be disagreement about the ecological benefits of the separating systems. A lot of people seem to think that it's fine to divert the urine off and store it in closed containers for later use, diluted, as a fertiliser, and we've seen this system in use at various places, including at least one big, well-established project.

Other people, however, raise questions about these systems. In particular this website claims that separation misunderstands the biochemistry of both the manure composting process and the urine breakdown. The solids dry out too quickly, aren't completely broken down into humus, and if stored in closed containers, often decompose anaerobically, losing nitrogen in the process. And the urine, even in a closed container, will inevitably start to decompose into ammonium within a few hours. By the time one starts using it as a fertiliser, it is essentially the same as using standard chemical fertilisers. In particular, it will be rich in nitrates which leach out of the soil very readily rather than being bound into the humus in a slowly-releasing form.

Does anyone have any definitive information about the biochemistry/soil science side of this? Although I'd like to make the system as convenient and inoffensive as possible, I'd like to be sure that we're not undermining the nutrient-cycling value.

Cheers,

Lucian