Studies on Succession of Ecosystems and Permaculture

Prach and Pysek had both done research on old-field succession in central europe, with some potential implications for Permaculture Design

Here are some summary articles

In short.. the settind drives how succession develops in abandoned fields in central europe.  Where abandoned fields with lots of open niches in agricultural settings are left to follow their own devices, the plant communities often become dominated by perennial weedy species like creeping bent grass, tansy, thistle, and nettle, and stay that way for a long time - with succession frequently arrested... where sites in less hammered landscapes develop more complex and woody vegetation... perhaps due to less nutrient availability.

Thus they suggest if you add a bunch of nutrients to a hammered landscape where the native seed source is compromised and then without continued intervention it gets taken over by weedy rhizomatous perennials, and our biodiversity plummets.  This may have implications for broad-scale permaculture designs.

The Scale of Successional Models and Restoration Objectives

Interesting short discusssion on succession in restoration (with Permaculture being a kind of restoration).  Provides a range of citation of processes that link to sector analysis and the temporal and spatial dance of "succession" with ecosystem processes.

"Even though we can develop "laws" of succession if we restrict the scale sufficiently, such a veiwpoint constrains completely our expecations and can lead to unexpected failure"

"...introduce or restrict processes so that theh influenctial set of processes at a site are reflective of the history of conditions suporting the patterns of biological organization and dynamics we are interested in establishing."

Just want to remind us that we are on the cutting edge of applied ecological research...

have been watching and playing with succession in our area for 40 years, and have just now seen a "change" in the succession of an adjoining field to the east of our property.

Initially it was mostly grasslands with a few dottings of pines and some alder swamp edgings and a few aspen edges..

In a normal succession you would expect the alder and aspen to move out into this open field, exactly what we were expecting..however in the past few years there was a change.

We had gotten a group of black spruce that we put in to make a hedge along the east roadside of the field to give us privacy..quite a few years ago..and there was maybe 2 or 3 large scotch pine, a couple white pines and a few tiny cedar dotting the field.

Well the alder and a few aspen have moved in but recently, the past 2 or 3 years the field is literally covered with tiny evergreen seedlings which are now getting large enough to be noticeable..It appears that those few evergreens and possibly those of neighbors have been producing prolific seed and they are changinig the entire sucession of the field from what we thought would be n aspen woodland to an evergreen woodlan.

Wanting to have a few food producing plants in this area we are hoping to bring in some apples and lums into this area..but the change in the succession on it's own was so amazing that we are kinda just going with it, but we'll put some of the fruit trees nearer our home..allowing the eevergreen succession to do its thing

Paul Cereghino wrote:

Thus they suggest if you add a bunch of nutrients to a hammered landscape where the native seed source is compromised and then without continued intervention it gets taken over by weedy rhizomatous perennials, and our biodiversity plummets.  This may have implications for broad-scale permaculture designs.

The succession from weedy grassland to climax forest, without human intervention, takes far longer than a few humans doing a study. 

So, the obvious implication for broad-scale permaculture... is that we have to speed the process and guide it in the direction we want.  Left alone, it might take a couple millenia to get an oak forest, but by applying succession in a managed way, we can accomplish the same thing in a human lifetime.

Whenever there is talk of 'natural succession' one should always bear in my one thing:

The fact that humans could come up with this concept of "natural" is because they've provided the conditions for it in the first place.

Open areas get populated by pioneers, brush, fast growing trees, then large trees, basically forever unless the chainsaw comes in.
But that's a phenomenon that didn't exist until mankind acquired the knowledge of how to hunt large animals.

If the earth still had all species of large - and I mean large - animals, a climax forest would be a rare sight.
You'd find it on steep cliffs and in other areas that large creatures can't reach, but on flatter land the elephants and rhinos would
see to it that large trees would not come up as a forest, but rather as small patches. And these patches would consist of unpalatable species.
The edible ones would repeatedly be eaten down to the size of a small brush - those towering beech forests that cover my country simply wouldn't exist.

I wonder what that means for us permaculturalists, keeping in mind Sepp Holzer's bonmot '... then you must do the pig's work !".
Don't we too need patchy forests like those to have maximum productivity ?

http://permaculture.org.au/2011/08/10/the-tree-that-hides-the-prairie/

I recently pruned my willow fedge, which I planted about 14 years ago to shelter the fruit garden from our strong winds, and I noticed succession in action! The willow took a little while to get estabished as it was very exposed initially, but it has been doing good service for at least ten years.
On the windward side I also planted an elder tree which I had brought up with us from our previous home. That took even longer to get going. Unfortunately it still doesn't fruit well, but has lovely blossoms. The elder is now shading out the willow and has made a space of about 12 feet in the hedge. I have a few other elders planted now outside the willow fedge and am looking forwards to having an elder fedge instead. I've never been fond of the willow; although it produces a good amount of biomass I have to be careful where I put the trimmings, since they have a tendency to root and start growing.

elder where there was willow

It's still a bit messy in this picture, as I have the prunings still to do something with, but the willow used to form a continuous hedge on the right hand side, but now I have a lovely elder tree instead

In other places the willow are starting to be shaded out by themselves and the brambles that have grown amongst them.