PERMACULTURE:  Great Concept, Pity About The Weeds.

Published in The Nimbin Good Times. December 2004.

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David McMinn

 

The basic principle of permaculture is highly commendable -  to encourage self sufficiency via the design and development of productive and sustainable gardens and farms. This is something that the world so desperately needs to counter the onslaught of industrial agriculture. Permacultural designs were derived from studying both natural ecological systems and pre-industrial examples of sustainable land usage. The originators of permaculture in the 1970's, Bill Mollison and David Holmgren, completely ignored one key factor: the environmental threat posed by many exotic plant species. There are several qualities that make plants suitable for permaculture - low maintenance, easy  propagation, vigorous growth and immunity to pests/diseases. Alas, these same qualities also make them prone to becoming serious weed pests. Thus there is a conflict between permaculture and the potential for creating new weed problems. Over the past 30 years, the history of permaculture is littered with numerous examples of bad design, where many recommended plants species have became serious weeds. These have spread into the surrounding ecosystems, reducing the land's productive potential and degrading the native biodiversity. What is at stake is the survival of native plant/animal species and whole eco systems. Millions of years of evolution snuffed out over several human generations, because of stupidity and a complete lack of foresight. Regrettably, permaculture has contributed to this ecological catastrophe. Peter Hardwick, the local bush food expert, commented that "in places like Hawaii, exotic plants have severely depleted native plants to the point of extinction, showing how bad the weed issue can get. Similarly, lantana prevents rainforest from regenerating. The reality is that there are places where lantana is still dominant 70 years after clearing. Some people try and justify lantana, but it just doesn't stack-up. How can anyone say that lantana is better than rainforest?" 

What may be suitable for a farmer in a developing country, may not apply to the Australian experience. A poor farmer would thoroughly cultivate his entire small plot to maximise his subsistence output. Nothing would go to waste. In affluent Australia, people adopt permaculture principles out of interest or a desire to produce their own food sustainably. There is no economic imperative to cultivate productive landscapes intensively. Thus the permaculture garden can quickly become infested with weeds, if it is not well maintained. These weeds can also spread into the local environment and cause more havoc. Landowners must then waste time and money to get rid of weeds, which should never have been planted in the first place. High cost herbicide also has to be used to poison the weeds, as there are no other viable options. Using weedy species is completely counterproductive to the basic objectives of permaculture, which aims to eliminate chemical use and reduce labour inputs. 

The following list are plants that I personally had problems with following permaculture guidelines in the 1980's. 

Abbreviations: EW - An Environmental Weed is a species which is a threat to the survival of native plants and animals. DN - Declared Noxious means that landowners need to take action to control this species on their property. NN - Nominated Noxious means that the species may be declared noxious at a later date. 

Brazilian Cherry
(EW) was one of the many species suggested for permaculture design. However, it is a serious environmental pest, as its seed has a very high germination rate and is spread efficiently by birds. We are having to pull out small plants sited hundreds of metres away from the nearest fruiting tree. Grumchiana and Jaboticaba do not seem to present a weed threat and produce yummy fruit. Always consider using these species as alternatives to Brazilian Cherry in your plantings. 
Coffee (EW). Unless you are going to harvest all the seed, do not grow this small tree. People buy a few plants with the fantasy of growing their own coffee. They quickly become discouraged after realising the difficulty involved in processing the fruited seed into the roasted coffee bean ready to be made into a delicious espresso late. Usually the plants are just left in the garden and seed not collected, thus creating a yet another weed problem. We ended up with a carpet of coffee seedlings through much of our garden. It took three years to finally get rid of the last coffee seedling. It is much, much easier just to buy your coffee, do the local environment a favour and support poor coffee farmers in Nicaragua, Timor or Kenya.
Ice Cream Bean (EW) was considered to be another highly desirable legume tree in the 1980's. It grows rapidly and is easy to propagate. The sweet pods were initially hyped as being delicious, but most people found them underwhelming. Thus the pods were just left on the trees allowing the seed to spread into the local forests. We have killed all the dozen or so adult trees in our orchard. This may be easily achieved by ring barking the main trunks and then poisoning any small re-growths that emerge. We still have dozens of small seedlings to get rid of.
Leuceana
(EW) is another vigorous legume tree from South America. It was widely promoted both in permaculture and farming during the 1980's for its fast growth and nitrogen fixing ability. It seeds prolifically and can quickly become weedy in our warm, humid climate. We tried to get rid of it from our garden for many years, but now a compromise has been reached. Every year the trees are stripped of their seed pods and trees cut back to their stumps.
Sweet Potato. Following Permaculture design, we planted sweet potato as a cover crop in our orchard. It spread rapidly, forming a dense mat so that mowing was not longer necessary. This was what it was meant to do. However, we only harvested a portion of the sweet potato crop, as there are only so many sweet potatoes you can eat in one season without becoming sick of them. This left a large food resource for the bush rats, which then proceeded to move into our house. We are still trying to get rid of sweet potato vines in our orchard. Apparently, the golden sweet potato is much less vigorous than the white variety. We grew the white much to our regret.
Tung Oil Tree was promoted as a source of tung oil, used in the production or organic paints. It just spread into our nearby rainforest gully - up to 200 metres from the adult plants in some cases. Fortunately, the trees do not sucker and, with one swipe of a chain saw, they die and quickly rot down. Even so, two years later and we are still pulling out seedlings in the forest.

Numerous other weedy species have been promoted by permaculturalists at various times. These included Black Locust (EW), Chinese Tallow Tree (NN), Cotoneaster (EW), Guava/Cherry Guava (EW), Honey Locust (DN), Kudzu (NN), Loquat (EW), Pampas Grass (DN), Paulownia (NN) and so forth. You get the overall depressing picture.

It was completely remiss of permaculturalists not to make people at least aware of the weed problems that may arise from following their suggestions. One can only assume that it was done out of ignorance, but to date I have not read any acknowledgement of the serious problems permaculture has created. Apart from the weed issue, the basic principles of permaculture are sound and highly commendable. Crucially, weedy species are not essential to the viability of permaculture, as there are many alternatives. 

Non Weedy Exotics. There are many non weedy species that may be utilised - Black Sapote, Chestnuts, Citrus, Figs, Jackfruits, Litchis, Longans, Mangoes, Pecans, Persimmons and many others. They may require more maintenance than those species from the weedy list, but it is worth the effort in terms of a healthy environment/garden and superior produce. For a ground cover, we tried Lablab, a vigorous legume from South America. This species grew rampantly for a few years and then died out. It could be assessed as a possible non weedy alternative. Shaws Creeping Vigna is another legume ground cover option, as are the various Native Vigna species. Friends have also successfully tried Ground Peanut.

Bush Foods
, native to Northern Rivers - south east Queensland, are an environmentally sound option. Numerous species may be grown in bush food setting - Bunya Nuts, Davidson Plum, Macadamia,  Ribeberry and so forth. They offer good prospects for permaculture design. Peter Hardwick is "at the native restoration ecology end of the spectrum of permaculture and into promoting bush foods. I love the original adaptations from natural habitat - such as productive forest edges and understorey stacking. I'm hopeful of a more reasonable approach within the movement and an acknowledgement that it was a mistake not to  include weed risk into the equation".

Permaculturalists have to accept that serious errors were made in promoting and using weedy species. This created huge problems for landowners in terms of time and herbicide required to get rid of their mistakes. Native ecosystems have been also saddled with a large influx of new weedy species with sever long term consequences. A fundamental re-appraisal needs to be made and potential weeds should be dropped from permaculture design. According to Peter Hardwick, "Permaculture is not responsible for most of the nastier weeds, but it's important that an organisation promoting ecological values and biodiversity addresses the weed issue in a responsible way. At one point permaculturists were saying things like 'plants of the world'. As if it was OK to spread weeds because they belong on the same planet! It was just plain naive. There's some great stuff in permaculture, and it's a shame that such a great concept has been wounded by a seeming inability to be more self-critical, because spreading weeds is not what permaculture is about".


This article may be downloaded from the Nimbin Plant Selection Guide - www.davidmcminn.com/ngc