stacking functions? simple description?

In one or two sentences, how would you describe 'stacking functions' to a person who never heard of permaculture before?

Do you have a good analogy you like?
(I'm already using eating your cake and having it too)

I usually say "It's getting multiple uses out of one element of your design.  Like a pergola that gives shade, has a gate to your garden, supports grapes and looks pretty."

It's like a garden knife or pocket knife.  One item, multiple uses.  Do that with item after item and you get a stable system.  For instance,  if your pocket knife is broken you still have your garden knife to cut things.

I guess I'd describe it in a "Getting the most bang for your buck" sort of way.  That's at least a phrase people are familiar with.  If you do a particular thing, see to it that it gives you as many "results" as possible.  

For what it's worth, I think the "stacking functions" concept is a mental exercise more than anything. It isn't an act that is unique to permaculture, it's just that permaculturalists place a certain emphasis on recognizing the multiple results of a given act.  Everybody stacks functions to some degree, some (permies) just think about it more.

To give another example, my wife and I were talking about this as she weeded onions and I worked on putting up some fence yesterday.  While weeding onions, she was removing some of the competition to allow better crop growth, could harvest plantain (to be dried and stored for medicinal purposes) and dandelion (to be used in a salad and/or as a substitute for hops in home brewed beer), was leaving enough weeds to allow mining of the subsoil for multiple crops, was creating mulch for the onions from the weeded plants, was getting a good dose of vitamin D, and was able to instruct our boys as to what she was doing and why.

As for my fence, the posts are eastern red cedar.  By cutting them instead of buying, I was able to save money, got to spend some pleasant time in the woods, thinned out an overgrowth of cedars in a few locations, was able to make brush piles (wildlife habitat) out of branches and tops, burned a couple brush piles (which the cattle and sheep will access for minerals), and I'll have a nice aesthetic fence to boot.

These are all great examples. I like the simple descriptions given, but not as much as my own.

"Two birds, one stone." It is simple and resonates across different design philosophies.

-CK

When finding solutions to problems, choose those with added benefits.

An apple tree will shade your house and provide food, whereas a shade tree just provides shade.

A pond with fish can provide nutrient rich water, capture runoff, and cut down on mosquitos.

Its like multitasking for your things.

Stacking functions means that you gain multiple functions from the various elements that make up your garden for food forest, rather than just one.  An old apple tree offers shade for people to sit under or for more delicate plants that don't like the hot sun, delicious apples, a trellis onto which a vine may grow, a source of leaves that can be used for mulch, and perhaps even a thick branch onto which you can tie a rope swing.

A single plant can offer food, fuel, fiber, soil stabilization, carbon for soil enhancement, a solar energy collector, and other many other benefits.

A pond or water feature can provide water storage for irrigation and other needs, habitat for aquatic life (fish, ducks, insects), serve as a flood-surge shock absorber, a swimming hole for hot summer afternoons or a skating rink in the winter, a reflector for sunlight (onto trees or a dark space), a habitat for plants that otherwise will not grow (cattails, willows, other useful plants) and aesthetic enjoyment.

Working together, individual components of a well-designed system create a synergy that one element by itself would not be able to contribute.  For example, a grey water system cleans and recycles water, provides irrigation, creates a habitat for aquatic plants that can then be fed to ducks and chickens, and may even serve as a heat-sink to keep nearby plants warm during cool nights.  As functional elements are stacked upon other multi-functional elements, the entire system becomes more productive, fertile, low maintainance, resiliant, and beautiful.

Mike Jay wrote:I usually say "It's getting multiple uses out of one element of your design.  Like a pergola that gives shade, has a gate to your garden, supports grapes and looks pretty."

Couldn't have said it better myself. BTW, I was serious about rhubarb. How many?

I guess I think of it as choosing elements in your permiculture or polyculture design that are multipurpose and/or multitask.

I think of stacking functions as actions, not so much a design principle.

Stacking functions is doing (or building or designing) something that serves more than one function simultaneously.

Here are some actions that I think stack functions.

Running the kitchen tap water to heat it up for washing dishes, but capturing it in a watering can for watering plants instead of just letting it run down the drain.

One morning this week was rather chilly (in the upper 30's F overnight) so I burned some trash in the RMH. We don't have recycling for a lot of our paperboard and other paper-y things, so we use them to start fires in our RMH. We have too much and didn't burn enough this winter so I want more gone. I stood over the RMH, feeding in burnable trash, with my hair still wet from the shower, and laundry on drying racks on the mass. So I was stacking functions by heating the house, getting rid of waste, drying my hair *and* drying laundry!

There are so many times we exclaim "stacking functions!" when we realize we're serving more than one purpose at a time. And of course now, in trying to recall more examples, my mind goes blank.

(Per the burnables pic:  before folks start telling me about reusing egg cartons - know that we have and do, when we can. Currently, we do not have anyone who wants to reuse them so our cup runneth over.)

Here's my simple description: passive multi-tasking.

We observe that nature stacks functions for the sake of passive multi-tasking , so now we engineer that stacking to serve our purposes.  

Take my banana trees, for instance. I observe that nature employs them to: create mulch, produce food, provide shade, and provide forage. I also observe that they require much water and rich soil.

So I plant them where they can most easily obtain what that need and moist conveniently provide for me: in a mulch put right beside my faucet. I know this isn't what you asked for,  but just for the exercise,  let's count the functions.

The pit serves as a place to toss debris and kitchen scraps (1), these decompose to make rich soil for the trees (2), the water runoff from washing dishes at the faucet--since we wash or dishes outside--waters the trees passively (3), the moisture and kitchen scraps attracts the chickens who profit from the shade (4) and get free food--both kitchen scraps and bugs (5), they scratch up the place and poop all over it to increase the fertility (6), and proceed to lay nutritious eggs 20 feet away under my shade trellis  (7); because of the abundance of rich soil produced, I plant my papayas right next to them and end up harvesting far more papayas than bananas (8); both bananas and papayas provide such great shade for washing dishes that we set up or laundry washing right next to it (9) which in turn contributes its water and nutrient to the system; since there remains slight moisture on the extremities of this system I plant moringa, chaya and giddem trees on the far side, thus harvesting two perennial vegetables and a third perennial fruit without even thinking about it (10);  since banana trees reproduce prolifically, the extra trees are chopped down for mulch on new tree plantings (11); the filtered shade of the papaya leaves are perfect for a tree nursery, so I put some fence around a small portion where I start some fruit trees (12); this humid microclimate in an otherwise very dry part of the world attracts chameleons and poison tree frogs that serve as science lessons for my kids (13), while the tropical feel of the place gives me a delightful spot to smoke my monthly pipe on a moon-lit night or enjoy a private conversation with a guest (14); all that compost activity is creating a vibrant microbial community that surely makes it into our own biology, increasing our resilience and vitality (15).

The stacking is, indeed, a phenomenon of nature that we observe, but in permaculture we actively copy nature's passive multi-tasking.

Weren't we looking for a simple description?

Many of these are excellent examples, but I think if we need to describe a whole system at length to get at the meat of function stacking, that we have departed the realm of simplicity.

-CK

Jocelyn Campbell wrote:I think of stacking functions as actions, not so much a design principle.

Stacking functions is doing (or building or designing) something that serves more than one function simultaneously.

Nathanael Szobody wrote:Here's my simple description: passive multi-tasking.

We observe that nature stacks functions for the sake of passive multi-tasking , so now we engineer that stacking to serve our purposes.  

Take my banana trees, for instance.

Chris Kott wrote:Weren't we looking for a simple description?

Hi Chris, both of these seem pretty simple and short to me.  They go on to explain a few systems in more depth but I believe the initial thrust of the OP was a 1-2 sentence explanation of Stacking Functions and/or an analogy.  Giving the additional longer example might get extra credit depending on the teacher.

I personally have trouble with the analogy part since I think of "having your cake and eating it too" as an idiom.  An analogy to me is more of a possibly unrelated example with clear parallels.  So for Stacking Functions, an analogy could be "Stacking functions is like a turtle's shell, it gives shade, protection, rain deflection and is pretty".  

Then again I really didn't like my English classes so I could be wrong about idiom vs analogy...

idiom

analogy

I suppose I am being facetious.  But I would definitely say that you are right in your grasp of the language insofar as those terms are concerned. Although if it literally says "this is like that," it's a simile.

"Having your cake and eating it, too" isn't, to my mind, function stacking. It's being able to benefit from what you have. "Killing two birds with one stone," I think, is the most simple analogy, but I agree, upon reflection, that it is a little vague.

Perhaps something non-idiomatic like, "Function stacking is choosing solutions that address many problems at once."

I am surprised that nobody brought up the example of fruiting hedgerows. A fruiting polycultural hedgerow, hawthorn-based with grafted pear, featuring pollarded hazelnut and a nitrogen-fixer (bayberry?), multiple varieties of cane berry, and perhaps some mulberry and/or other applicable fruit trees (stone fruit and apple) would provide fruit, hazelnuts, pears, and berries in the realm of human crops; pollarded firewood, fruit tree prunings either as rabbit gnawing toys and browser food or for smoking meats; medicine and tea ingredients (raspberry leaf, mulberry leaf, etc.); pollinator habitat and food season-round; shelter from wind dessication and erosion; a sacrificial crop for migratory welfare fowl; shelter from predators and food for songbirds and other wildlife; a physical barrier to livestock and many larger wild animals; seasonal leaf mulch, as well as trapping windborne organic matter and sediment; and because of the variety of different root systems and the sheltering nature of the hedgerow on the land, the soil in which it sits would also act as a soil life bioreactor or nursery, the perennial nature of many of the root systems nurturing a fungal-dominant soil.

And it looks pretty.

-CK

EDIT: But I have to say, Mike, upon reflection and rereading the whole thread thus far, your first two-sentence response is probably the most complete and succinct. Bravo.

My favourite example is that of a properly integrated chicken system.

Most people round here have a static run of bare earth and buy their chickens feed.

We are building ours right from the outset with the idea that, in addition to giving us eggs, they will be a primary factor in cycling nutrients through our systems. It is designed for easy wheelbarrow access, will house our compost heaps, and our biochar burn pit. Waste goes in at the top of the slope, and nutrient rich mulch comes out at the bottom. When this is fully setup we will get, eggs, better compost, fewer weeds, inoculated biochar and a team of bug eaters to patrol the garden from time to time. Overall there should be no extra workload to look after these hens as their care will be naturally integrated into our other tasks.

Now ours won't be able to hit every possible stacked function - we are limited by our situation to a static setup, and foxes are a huge problem, but we will do well from it overall. Much better than our neighbours for whom their chickens increase both cost and workload.

a sheep can be a lawnmower that gives you milk & warm shirts.

Abe Coley wrote:a sheep can be a lawnmower that gives you milk & warm shirts.

So what's the difference between multi-functional and "stacking functions"?

Nathanael Szobody wrote:So what's the difference between multi-functional and "stacking functions"?

On the one hand I think the difference is mainly semantic, but on the other I think that difference is significant.  If one aims for "multi-functional," one has succeeded as soon as two functions are noted.  But if one aims for "stacking functions," one never fully succeeds as such.  "Stacking" is an active verb, and so it is (or can be) continuous; one can always continue stacking function upon function, in theory at least.

I think this is probably most important when designing a system, versus when evaluating an existing system.  If your goal in a design is multiple functions, you might likely check out much sooner than if your goal is stacking functions.  If "stacking functions," then, results in more (or more acknowledged) functions, this positively affects other issues, such as designing for redundancy.

Wes Hunter wrote: "Stacking" is an active verb, and so it is (or can be) continuous; one can always continue stacking function upon function, in theory at least.

Precisely. 'Multi' is a fact of nature. 'Stacking' as a permaculture term is all about design,  to make the 'multi' exponential.

My front yard has a 'green fence' for  privacy about people looking in, and it happens to be fruit trees that give me fruit. My opuntia (cactus) collection is decorative, a great deterrent for the neighbor kids NOT to climb the fence, and provides me paddles and fruits to eat. And so on. A tree is the classical stacking function item... provides shade... may help block a view... gives me fruit to eat... holds soil in place... provides habitat... area microclimate for raising certain things here because it provides filtered shade and hail protection. I will use a tree to describe the idea to non-permies.

For me, stacking functions means, "Having one thing serve many purposes"

Some Examples:

My garden beds are edged with logs. These make great seats, hold up the dirt, keep the weeds out, generally keeps ducks out because they don't climb on the logs, AND, they're really fun for my kids to walk alongm jump off of, and learn balance on.

Hedges, like Deb Rebel said. Mine produce berries, are bird habitat, are barriers that keep my ducks in certain areas, and give the deer something to eat rather than my fruit trees.

My herb spiral: It's snake habitat, a place for my herbs to grow, it's pretty (that's a purpose!) and it's a place my kids love to snack from.

Sometimes, stacking purposes isn't so much about intentionality as it is about discovering, appreciating, and utilizing all the uses that something has. By discovering those uses, we can encourage and re-create them elsewhere, too!