4: Social Structure: Niches, Relationships, and Communities Species, species niches, and species relationships
Box 4.1: niche analysis: everybody does it
Box 4.2: the principle of multiple funtions
Box 4.3: the principle of stress and harmony
Box 4.4: the competitive exclusion principle
Box 4.5: the cropping principle Multispecies interactions: frameworks of social structure
Box 4.6: the principle of redundancy Social structure design: anchors and strategies
Feature article 3: natives and exotics, opportunists and invasives Box 4.7: the polyculture partitioning principle Box 4.8: ecological analogs Chapter summary
Heaps of theory that gives one a lot to ponder, especially on the first reading. This time through, I was especially struck by the admonition to provide redundancy in the essential functions needed to support the forest garden. For me, that means doubling and tripling up on pollinator plants and parasite habitat. Probably more nitrogen-fixing can't hurt either. And shade. Here in the high mountain desert, is too much shade possible?
I really needed to reread the section on anchoring design, I had forgotten the emphasis on predator habitat. As I learn more about natural predators to the codling moth, building good habitat is going to be critical and I need to build it into a continuous improvement program here. As if to reinforce this idea, OSU's integrated pest management research outfit has a summary of codling moth predators and it says, among other useful points, "The most important codling moth predator species are Neuroptera, Thysanura, and Heteroptera, although some Coleoptera (like coccinelids and pentatomids) also can have an important impact on codling moth population levels. All these predators are very generalist, so the impact on codling moth population will depend greatly on the relative availability of other food sources." If I want them, I have to make sure the other food sources are present in abundance.
For those of you anxious to DO SOMETHING with all this theory, and for those of you feeling overwhelmed with where to start, rest easy: there are worksheets to help figure out how to fit plants into niches. If you want to jump ahead (they are mostly referenced in Volume 2), Jacke and Toensmeier have them on a website. They will start to make sense now even though you are jumping ahead.
I tend to look at worksheets like these as examples of how to organize my thoughts, and then proceed off in my somewhat lazy, misguided direction. The desired species niche analysis (Worksheet 1) has a lot of boxes to fill in, in the interest of due diligence and completed staff work --the kind of detail that would be extremely useful as you are getting to know plants. So for planning my ciderapple guilds, I made an abbreviated version that I thought I'd throw up here for your inspection. I'm not saying you should use my format. In fact, just the opposite. Heck, I even invented a category in the layers that isn't a layer, so don't copy me! It works for me, and that's who it's for.
I think by reading this chapter, understanding your own site and getting some basic plant knowledge, you can come up with a much better version for yourself. But I do think building your own database of plants is an extremely useful exercise--especially if you are new to gardening or taxonomy. Just understanding that dill, fennel, lovage, parsley, carrot, and angelica are all in the same plant family and what that means (happy bees) and what it doesn't mean (you can choose from annuals, biennials, even perennials; some have a root yield, some aren't usually grown for roots but could be like Hamburg parsley) gives you so many more options in plant selection. I don't even list plants that I know won't grow in my climate, but I do consult the resources on Toensmeier's website and especially his links to Useful Plant Profiles when I am working on my database.
I'm a spreadsheet person. If I hated computers, the same thing could be done on colored index cards. In fact, there might be a huge value to doing it that way, so you could sort your holy cards visually into guilds. That would be cool. If we ever get to Volume 2, I'm sure we'll talk much more about this. But some of us are very concrete action oriented learners and I thought I'd throw this up as a way to start working with the theory right away.
(For those of you who learn best by working through all the theory in an orderly fashion THEN proceeding to action, just ignore this bit as an irrelevant rant.)
And on another point: what did you all think of the distinctions between guilds and polycultures?
The niche conversation really gets to the heart of the plant and what it can do in your garden. There is so much about plants you never would have thought possible or probable. It expands our assumptions about what plants can do and what polycultures/guilds could become.
As with the last chapter this is very dense information. They really got on the nitty gritty on plant theory in micro and macro detail. I knew of guilds and polycultures and the reread has got me all fired up about making my own forest garden.
I liked the mention of evidence supporting the use of compost tea which supports fungal endophytes. Fungi protect plants from pathogens and herbivores but they mention they're only really found in grasses and conifers but that will change. Then the use and recipes of compost teas can be tested on how well they work.
They mention how weeds are a symptom of poor ecosystem design. Fill up those niches
Although to be honest, the system complexity is so much to digest in the first read that I haven't cracked open volume 2 yet. Going through this book, I've found myself becoming more thoughtful and less anxious to "DO SOMETHING" now for fear of doing something rash and irreversible. Kudos to the authors for the research and bravery it must have taken to get started on the experimental guilds they describe in the tour of Paradise Lot in Perennial Abundance.
I found myself blocking the basic plant strategies: competitors, ruderals and stress tolerators into being analogous to the animal stress response frameworks of fight, flight, and tend/befriend respectively to make them easier for me to remember.
I've had to reread the food web section a couple times as my initial inclination was to start thinking about it in terms of an energy pyramid and to try to back into how little space one would hypothetically need in order to be able to support various human diets. It seems like we have more than just the square footage variable to play with though. We could shade our diets towards herbivory to extend/avoid that second law of thermodynamics about some energy being lost through every transformation along the food web. We could also start looking at the ecosystem through something like a factory stock and flow system and seek to smooth production over time to avoid booms and bust cycles of various booms and busts in various populations along the web. I'm a little rusty on systems dynamics, but it seemed like in most cases this involved ferreting out and removing bottlenecks within the system, often by injecting additional diversity.
Thanks tiny ad, for helping me escape the terrible comfort of this chair.