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Tuesday, September 7, 2010

Catha edulis, from Coolbellup to Candi Kuning

In a suburb near Fremantle, Western australia in 2002 we located a large Khat tree (Catha edulis), a stimulant commonly used in East Africa, The Arab Gulf states and Madagascar. Its is a Medium sized tree most often found as a highly pruned shrub that is grown for its fresh shoots which contain the stimulants Cathinone and Cathine.

These trees were and may still be somewhat common in the older suburbs of Perth, Western Australia. Our investigations through local nurseries suggest that its was propagated by nurserymen over a number of decades beginning in the late 1950's as an ornamental plant. It suits the soils and climate well and it is indeed and attractive garden plant resembling in many horticultural features the Photinia. 

Figure 1: The Mother lode Tree 2002. This is the largest seed load we have ever seen on a Khat tree. This tree has now been felled
Figure 2: The Foliage of the type of Khat trees common in the suburbs of Perth.
Figure 3: Seed pods as they hang in clusters from the tree
I First became aware of this tree in 1996 when we saw a tiny specimen in a colleagues nursery. There was a sense of hush-hush about it and a story that it contained a chemical like "Speed" (Amphetamine).
We were then surprised to find a large tree in a friends grandmothers backyard in and old Perth suburb, so i sent a pressed sample to my colleague who confirmed its identity, with equal surprise. I was to find several more trees during my time in Perth, and hear of a great deal more.
It was in 2002 while cycling to Fremantle that i spotted two east African looking gentlemen high up a tree. This being the tree pictured in Figures 1 -3, from which i had already been collecting seed the week before. I approached them to say hello and hopefully learn more about its use.
At first they were hesitant, but when it became clear i was familiar with this tree they opened up. These fellows were from Kenya and were harvesting for themselves and their Ethiopian friends. They chew it socially with friends, listen to music and drink some beers. This seemed a more informal ritual than the Qat houses of Somalia and Yemen, where the Islamic customs exclude Alcohol.
These fellows told me of how they used to grow it in the moist fertile highlands, renting land between Coffee plantations in order to grow Khat. By digging a hole and planting cuttings they would establish trees that could be first harvested some 3 or 4 years later, not unlike the timespan to grow coffee itself.
When queried on seeds, they told me unequivcally that Khat does not grow from seed, as they stood against a backdrop of a seed laden tree. I understood this though as it is a common understanding with many crops that they are not grown from seed if a cutting will bear more quickly and reliably, this is the undertanding ofthe farmer, not the biologist like me, who is most interested in aspects other than yield.
This tree, they told me, was poorly managed - too big! The leaves were tough and weak, a good tree would be pollarded, that is cut off much lower and encouraged to reprout vigorously. It is these juicy crisp and low tannin shoots that are most valued.
I never saw those men again, though i spoke to the owner a few years later and the tree had been savagely pruned. The owner was dismayed at the Car loads of Africans who would turn up in the front yard any time of day or night climing the tree and taking away branches. He was concerned about litigation ifthey hurt themselves and was intending to remove the tree. Sadly this story is common, many trees i have known, and many people have told me their stories of their Africans in the trees, despair and eventual arboricide.
Those seeds however were distributed Australia wide and Worldwide.

I had the opportunity to taste some quality shoots in Perth from a recently coppiced tree. The flavour and texture was indeed far better, slight tannins and sweetness like sucking on a teabag. And a pleasant aromatic flavour. The effects were subtle but definite. Those expecting Amphetamine should be ready to be disappointed! firstly one has to chew some 150 - 300g of fresh shoots, a hefty amount to the unaccustomed!
The tannins are still present and so pucker the mouth.
The effect i can liken to Strong cup of Tea, and in exactly the same way it relaxes and invigorates. Chemically it may be amphetamine but its effects are so mild that only chemists need care. It enlivens conversation without inebriating, it is pleasing, but the cost, that of chewing so much herbage im sure will restrict its use to ethnic circles.

The compound itself is unstable, and extremely difficult to extract and stabilize. Even dried leaves only contain the weaker Cathine, perhaps useful in weight loss or congested sinus. As a starting point for drug synthesis the plant is a dead end.
Cathinone is not the same as Methcathinone, a street drug manufactured from Sinus pills and much stronger and more stable. Nicknamed "Cat" or "Kitty" this im sure has led to confusion among law makers and they have now banned the plant in two Australian states. So this plant becomes an unfortunate casualty of the War on Drugs, which is silly, because it is really the same as banning Coffee, Chocolate and Tea plants in what it achieves, while all the street drugs are made from Pharamceuticals.

Part two
In 2003 We travelled to Bali, Indonesia, to explore the Island for a month. Part of this exploration took us to the Bali Kebun Raya (Botanical gardens) at Candi kuning near Bedugul in the Mountains.
We took with us on our trip seeds of the Khat tree and donated them to the Botanic gardens.

Part 3

I returned and relocated to New South Wales where i continued a long running interest in Khat. On the east coast the plants were much more rare, but multiple forms existed.
There were even some collectors beginning to cross pollinate specimens and create horticultural hybrids.One such hybrid is the Cultivar Vienna white, a hybrid of the Red and Green forms of Khat (figure 4), This was bred by a collector know as "Planthelper" living near bangalow, west of Byron Bay on the Northern New South Wales coast.
Figure 4: A "Vienna White" hybrid of the Red and Green forms bred near Bangalow NSW 
Figure 5: The Narrow Leaf form of Catha edulis from Southern Africa
Figure 6: The Narrow leaf form of Catha edulis showing leaf type
Nearby close to Lismore, NSW are Narrow leaved forms of the same species that look very different (fig 5 & Fig 6). These appear to originate more in the Southern range of the species and can be found in South Africa where they are also used (van Wyk & Gericke 2003).
Other species have also been grown and may contain similar compounds to Catha, such as the widespread genus Maytenus.
In 2009/2010 Hybrid seed of the Red and Narrow leaf Catha edulis became available.
When we returned to Bali in December 2009 we were pleased to find fellow plant collectors there had Khat trees amongst their collections.When queried about its origin we found it was sourced from the Kebun Raya and so we returned to the gardens after 7 years and easily located the thriving tree in the Medicinal herb gardens.

This has confrmed to us the value of Amateur plant collectors giving back to Public gardens, not just in your own country but when travelling abroad.  
It is our intention to continue to donate seeds and plants of useful species to public gardens worldwide and assist in their dissemination and study


van Wyk, B. & Gericke, N. (2003). People's Plants: A Guide to Useful Plants of Southern. Africa. Briza Publications, Pretoria, South Africa
Reccomended reading

Rushby K. 1999. Eating the Flowers of Paradise: One Man's Journey Through Ethiopia and Yemen

qat page

Ka'apor Forest Ethnobotany

Footprints of the Forest: Ka'Apor Ethnobotany- The Historical Ecology of Plant Utilization by an Amazonian People (Biology and Resource Management I)

Some Titles we've hand selected in refernce to this Post

Monday, September 6, 2010

300 year old Food forest in Vietnam

300 year old Food forest in Vietnamese Suburb

Geoff lawton discovers a 300 Year old Garden tended by a Vietnamese family for 28 generations.
I love this Clip because i too search out old suburbs and where i always find the most interesting plants and emergent ecologies.

Old soils built up layer by layer from gardening and human activity, with Domestic plants and animals that have thrived over centuries of climatic variation. In Australia this situation is easy to find but like everywhere becoming a more and more scarce resource as cities intensify and modernize.

Old Public gardens are also very valuable for the Permaculture designer as they provide not only the tried and tested propagation material to start new gardens, but also the knowledge of what mature plants look like, their accumulated community of associated plants, wildlife and soil biota.

Finding an ancient Oak or mulberry, or in the tropics a 100 year old Mango tree allows you to study what each tree does to the soil in which it grows and the plant nutrients, deep profile soil carbon qualities, or surface O-Horizon "duff" or the allellotoxins that species may bioaccumulate. A native example i recall from Fremantle is the community that forms about rottnest Island Pines (Callitris preissii), whoe duff and possibly allelotoxins create a habitat that allows the growth of a Pellitory herb, which in turn is the sol food source of the Blue skipper Butterfly. We do not yet know what range of special habitats exotic species are creating that will foster unique niches for increased biodiversity, although we have evidence that Old Moneterey/Radiata Pine groves provide a rich habitat for rare native Ferns, Mosses and terrestrial orchids. These habitats then also support the species that depend on these plants. The importance of Mature pines to endangered Black cockatoos is well known, and Urban Mango trees are well utilised by endangered fruit bats and local bird species.

Old trees in mature urban settings allow study of how exotic plants integrate into the ecology and how they interact with native species and provide valuable habitat. What kinds of lichen,moss, algae, vascular epiphytes and fungi adapt to its bark? What invertebrate diversity lurks among the canopy, on the bark and in the rootzone? What structural diversity does it provides for nesting or feeding Birds, Mammals or reptiles, and what epiphytes like to settle. And to humans what are the properties for Ammenity planning? Shade? longevity?  root stability, spread  and invasiveness?. Without this evidence a designer cannot design systems that are truly sustainable.Without real examples to survey and quantify we remain in the dark working with a very rudimentary theory based approach to Urban ecosystem design.   
These old gardens are of immense value, not only because we are working with species that do not occur naturally together, being separated by geographic boundaries, but also because many of our most valuable cultivated species are becoming very rare or are already extinct in truly wild settings. Wild Apples in Afghanistan or Wild Vanilla in mexico are on the verge of disappearing before we know how their original ecosystems worked. 

Food Forest Theory

Forest biochar

Biochar 101 

Biochar or Agrichar is doing the rounds in the news as a solution to a range of problems, including declining soil health and Carbon dioxide emissions from Industry and Agriculture.

Biochar is created by burning organic materials in low oxygen conditions so that a proportion of the carbon does not escape as Waste gases but stays behind as a solid and relative inert form of carbon we commonly know as Charcoal. The lack of sufficient oxygen prevents combustion to the end point where only mineral salts remain, known as Ash. Ash contains plant nutrients but it is caustic and water soluble so what canot be used quickly leaches away.

Most Charcoal is produced for industrial and fuel uses and ends up being burned anyway.The better industrial charcoal is made from Trees either in plantation or from felling natural forests. In this setting Charcoal is a great waster of a natural resource, as only 15-35% of the Carbon in Wood is retained in the marketable product.

However, Change the intent and feed stock origin and the whole game changes. Better Biochar is made from Low value organic wastes such as husks, shells, sawdust, short fibres, cleared brush and palm wastes to name a few, interfere greatly with cropping and tillage or general operations in Farming, Industry and forestry. They are generally low in plant nutrients and so naturally slow to break down, they do add some soil organic matter but often with great nuisance. They may contain inhibitory compounds that retard the growth of the next crop, or may harbour disease for the next season. Left to compost naturally the loss of carbon is almost complete with very little joining long lasting slow soil carbon pools. Any organic gardener will lament the sheer quantities of mulches and manures they have carted onsite, only to see it swallowed up by the soil. There is benefit, but it is easily undone by a few years of neglect, and it is a constant struggle to build and mantain on farm soil organic matter. Because of this, carbon that can be fixed by conversion to stable black carbon is a highly efficient gain and not a waste.

One of the benefits of Biochar is that it joins a store of carbon that is extremely resilient and long lasting. Charcoal is used by archaeologists to date prehistoric human settlements, and seams of charcoal exist from when land plants had only recently evolved. Even today many ferns like charcoal in their potting mixes, or will not germinate in the wild unless there is charcoal in the seedbed.

Biochar complements other Active and passive pools of Carbon in the soil by improving soil structure and decreasing bulk density so that roots, fungi and soil fauna can move around more easily. Chemically it helps form aggregates that stabilize other soil organic matter against loss by oxidation.Biochar does not replace living soil and Humus, it protects and complements it!

In this way a yield from an annual harvest of waste Peanut hulls, converted to 20% of its volume in Char and re-incorporated represents a boom to stable soil carbon levels that is unheard of by any other means within that time frame. It is also produced onsite or nearby and so is not robbing peter to pay paul.

Because Biochar is bulky but light and full of pores, it decreases the heaviness to the soil, helps it hold more water and more air, and helps prevent tight compaction. In amongst these spaces are sticky chemical sites that hold onto plant nutrients and slow the leaching process.

The Video

The clips show a man in Hawaii using Biochar to turn a carbon rich but infertile site into a rich Garden.
Rank vegetation in degraded areas`after logging and regrowth offers a ready onsite source of carbon.
Using a simple method the materialis converted to a Biochar that enhances the local soil.

Our own method we developed several years ago is very much like this method. Its is Low tech, used onsite materials and apart from simple labour, which you supply yourself, is free.

Our own methods used more grasses, like lawn clippings, Vetiver, Bana grass, bamboos, as well as wood prunings and woody fruits pits and capsules from Fruit and ornamnetal trees. By Turning the Hard,noxious, diseased elemenst of the garden to char they are defused.

Now in the tropics the use of Palm wastes including fronds, seeds, sheathes and trunks is most appropriate.


Biochar 2

Biochar 3

Railway Estate Community Gardens

Originally know as the Diversity Gardens, this multiple acre site is a community garden managed by the Townsville City Council and its allotment holders.
The Intention of the gardens was to support traditional gardening practices and foster intercultural interaction and sharing of knowledge and skills.
"The Community Diversity Garden was established by the Townsville City Council
in collaboration with the Federal Department of Family and Community Services,
Multicultural Affairs Queensland's Local Area Multicultural Partnership (LAMP)
Program and the local Community. The planning and creation of the Community
Diversity Garden was undertaken with the participation of various community
groups and individuals."

It is currently undergoing a renewal of Interest with many new members and community groups taking on Plots and getting involved.

The Gardens are supplied with irrigation lines so that each plot has access to mains water and plots vary in size , though ours is about 8 metres wide by about 26 metres long.

The gardens members come from a wide array of Ethnic backgrounds, some are Australian Born, others include Papua new guinea, The Philipines, Greece, El Salvador and Fiji.

These members bring with them their own gardening styles as a fusion of Traditional and their own ingenuity, as well as Traditional crops and the knowledge of how to grow, harvest and prepare them. We will showcase some of these in future along with Traditional names and specific information on use.

The Papuan gardeners bring Aibika, Pit pit, Sugar cane, Yam, Cocoyam and Cassava, The El Salvador Gardeners bring Tall Maize for making traditional dishes, Squash fruit grown for their edible seeds, Choko vines and rare fruits like spanish lime (Melicoccus bijugatus) , The Philipino gardener has planted perennial vegetables like Moringa and Thai pea eggplant. And everybody grows Bananas, of several kinds.
These plants get widely exchanged between members along with the information on how to use them
They have already instructed in when to harvest Bananas, and i have taugh them that the weedy groundcover they are always trying to remove, is actually a Nitrogen fixing groundcover called Desmodium they would do better to simply trim back and drop as fertilizer. In future i will quizz them more on their plants, their uses and recipes, and i will introduce them to alternative legume groundcovers and other useful plants

We have gained access to a plot, an overgrown one left vacant by the Phillipino Gardener. We inherit a range of plants, and we are already adding our own to the inventory

My Papuan neighbour was happy to see me planting a seeded Breadfruit (Artocarpus camansi) near our boundary, these are popular in PNG and the seeds are eaten as well as the fruit. Our seeds came from Bali, where it is known as Timbul, but it is the same plant.

We also bring many varieties of Basils, Chillis and Pawpaw/ Papaya. We are also planting Pepper vines, Vanilla , Basella, Bitter Gourds and Winged beans on the fences.

The Plot : We are removing and composting the banana trash, fertilizing with Dolomite and Gypsum and trimming back all weedy and dead growth to serve as a mulch layer to improve the sandy soil base. In future we may start turning woody waste to biochar.
This will be our first truly Tropical Food forest, though we have built them before in the Subtropics. There is a lot to learn, but the other members are very helpful

Saturday, September 4, 2010

Elements of a food forest

Elements a food forest
A food forest is an increasingly common term that has taken hold in alternative gardening circles, however it describes a very old concept. It describes complex Agro-forests, forests created by humans, intentionally, primarily for satisfying human needs, which approximate the structure and function of a natural forest.

The formal study of these systems is relatively new even though examples of traditional food forests are found throughout the Americas, Africa, South and East Asia and the pacific. Each one has its own structure and species composition dependent on local ecological conditions, tastes and availability of planting materials.

Food forests have a multifaceted value to environment and society, their strength lies in their ability to sustainably protect the land, while also providing multiple nutritional and economic options for the owner with very low input level of materials and labour. Food forests are also not just about food, they also provide Shelter, Fuel, medicine, forage and game. They can provide Aromatic oils and resins, timber and craft goods for sale. They also provide a range of ecosystem services such as soaking up nutrient and microbial pollution, retaining and building stable soils, humidifying, rehydrating and cooling landscapes. They have great conservation value in their ability to provide habitat for many wild and semi wild species, especially birds,most especially when they provide islands of sanctuary in a sea of fields or farms.

They also create a very livable landscape mosaic when interspersed with wetlands and grasslands. As a species we enjoy a wide variety of foodstuffs and goods that are found in multiple habitat types so it is useful for us to live on the edges of 2 or more habitats. One of the most habitable areas of all is near these anthropogenic food forests.

Establishing a piece of viable human habitat is not a difficult thing. You are already doing it when you live on a piece of land and return any domestic waste to the site.As in amongst what we call waste are seeds and other propagules just waiting for an opportunity, waiting to be left in a rubbish pile where they may find enriched soil conditions and germinate. Many of these plants are dispersed by large animals in their wild habitat. Animals eat the fruit along with other fruit and herbage and deposit neat piles of fecal micro-enrichment far from the parent tree. Our relatives, the great apes, are major seed dispersal agents and probably played a role in the selection and evolution of the tasty fruits across Asia and Africa today, some biologists suspect that the reason for the lack of tasty tropical fruits in Australian rainforests is a lack of primates.

With the selective force of many animals flocking to a particular tasty tree, and then spreading its progeny all through the forest in radiating seed shadows, repeated year after year, generation after generation it is not surprising that fruits have been fashioned to be bright, colourful large and sweet, just like Primates prefer. Our closest relatives, the chimpanzees, have been studied for their effects on seed dispersal in their native habitat. Some seeds are swallowed whole, and deposited later, while others are suck free of pulp and the remaining Wadge, a compressed lump of skin, fibre, pulp and seed (Goodall 1986), is dropped or hurled back into the forest. Studies on the germination rates of seeds from these Wadge parcels showed germination and survival rates greater or equal to defecated seed, and much higher than seed in fruit left close to the parent tree. Think about that next time you are spitting pips from a Watermelon or Mandarin! We are not so different.
Humans don’t swallow so many fruit seeds anymore, we even specialize in breeding fruit with fewer or no seeds! And when we do eat seeds, unavoidably, we flush them to sea or bury them in great underground anaerobic vats (Septic tanks).What we do, increasingly, is compost. Composting is a sanitary means of disposing of all manner of organic wastes and recycling them back into soil food. In theory thermocomposting sees the materials auto-generate heat as the microbes metabolize foodstuffs, this activity raises the temperature up above 60C and self pasteurizes the pile. It basically cooks any pathogens, insects, seeds and other items and renders the mix unattractive to vermin. The heat kills many seeds and this is the kind of compost you would put on your annual garden beds. The other more common compost, often by neglect more than intention, is more of a repository bin for scraps. They are better covered above to exclude vermin, but open to the earth below to allow free movement of earthworms, slaters and other benign decomposers to and from the pile. It is in these piles that we might throw fruit pulp and pits, non weedy leaf and trim, gnawed dog bones, ash from a barbecue or fireplace, and all sorts of other things that don’t attract flies, or bears!This enrichment supplements the natural succession of the area around Human by concentrating plant nutrients, and by seeding directly with our preferred fruits!
This system has been going on for millennia. This kind of open backyard tip where the chooks and the dogs eat the scraps and all thats left ends up in a big old heap may be as old as gardening itself. Studies on plant domestication suggest that these midden gardens were important sites for domestication of tree crops. Bringing seeds from distant places and discarding the seeds in fertile ground created opportunities for hybridization of distant relatives. This process continues today especially among people living adjacent to forests and harvesting wild foods. Building a food forest involves tickling the systems of forest repair by first understanding and observing what happens when we do nothing.
Weeds will blow in, grass will grow rank and be overtopped by weedy shrubs and legume trees. After a few years a low canopy may form and the edge of the new forest may be a tangle of vines, and shrubs with small bird dispersed fruits.
Under the establishing canopy partially shade tolerant bird dispersed species will sprout. These will shoot up and overtake the scrubby layer and form a higher canopy. They will fruit and in turn attract more birds which will take and deposit more seed.
In time perhaps larger wildlife will bring in large seeded species that are quite shade tolerant, these will slowly establish and wait for a small gap in the canopy to make a push for dominance.
We can do this too, the difference being control and speed. Control of species composition, control of speed of formation, and control of lifespan before the forest is reopened to a new cycle of rebirth.
Of the thousands of species of direct use to people, and the thousands more that support desirable wildlife or play important roles in the ecosystem we can learn to select and build artificial forests of extremely high utility.
For ecosystem stability it is hypothesized that a mere 15 species is necessary to stabilize and ecosystem, however not all species are created equal in terms of importance. So it is important for use to understand the concept of functional groups within ecosystems if we desire to create them.
I’ll be focusing on some of these in separate articles as we go along, they will include Nitrogen fixing plants, Fungi, Decomposers, Plants that bio-accumulate minerals from deep in the soil strata, Pollinators, Grazers, Predators, Pathogens and Parasites, Weeds and Disturbers.
We have a lot of reading to do ourselves and I realize the terms used are not perhaps what ecologists use, however they are the functional groups we work with.

Saturday, June 26, 2010

seed savers

Left from 12 'o clock;
Dolichos lablab, Pongamia pinnata, Crotalaria, Dolichos lablab cv Koala, African cowpea, Dolichos lablab cv Rongai, Crotalaria, Phasoleus lunatus cv Madagascar bean, Dolichos lablab cv. hyacinth bean, Eneterolobium cyclocarpum, Mucuna pruriens var utilis, Acacia auriculiformis, Samanea saman - Rain tree;
Pigeon Pea.

Biodiversity comes in many forms, one of the most beautiful are seeds and among the seeds the legumes stand out in their array of shapes, textures and colours.
Like vegetal jewels, cool and shiny they can fascinate the collector

They also have some real applications
Dolichos bean, also known as a seven year bean, hyacinth bean, lablab and many other names is a vigorous tropical and subtropical bean from the old world.
Its used as both human food, as animal fodder and for soil improvement. Cultivar ‘Koala’ was bred as a high protein replacement crop for soybean, yielding up to 2 tons per ha of beans.
Cv. Rongai is anolder variety that creates masses of Nitrogen to beef up tired soils as well as a high protein fodder crow for cattle
The black seeded hyacinth bean, possibly cv. Highworth, is a vegetable crop in Asia where the young beans are added to stir fries. In remote areas and places that are cash poor, just one such a bean vine would make a significant contribution to family needs. With increasing prices for soybean due to industrial uses, poor people in Indonesia cannot afford to make tempeh with soy. Studies have shown that lab lab can be substituted and can also be grown by the villagers themselves reducing dependence on imports.
In terms of establishing semi-wild food forests all cultivars have a role in establishment, in gaps and on the edges where a fast growing sunlight demanding vine can take hold.
The Mucuna bean is similar, also known as cow itch, velvet bean or cow hage. It is also a very vigorous bean used for soil improvement and in some cases for human food and medicine
In Honduras it has been used as an interplant with Maize where its nitrogen fixing ability and biomass accumulation makes it possible to build organic rich soils and maintain maize yields for many years, even on slopes.
The bean itself is rich in Levo-dopa, up to 6%, which is used to treat parkinsons disease. L-dopa is the precursor of the neurotransmitter Dopamine, which does many things including helping coordinate fine motor skills, but also things like libido and mental motivation.
Mucuna bean meals are sold for Body builders as well as people feeling flagged by modern life. In Indian Ayurvedic tradition it is known as Kawanch and used to treat problems such as erectile dysfunction. Seeds are ‘mitigated’ before use by boiling in milk and removing the outer seed and embryo. The bean meal is then dried and powdered, the milk is considered toxic and thrown away.
The effects of the bean have been reported as increased vigour and sense of well being, increased sexual arousal and libido, stimulation of growth hormones. In general it has an anabolic activity (growth and musclemass increasing). In some cases a side effect of ‘hypergrowth of the penis’ has been reported LOL J.
The vine itself is also interesting with analysis of its leaves and stems showing the presence of hallucinogenic tryptamines, albeit in small amounts. The compound Dimethyltyptamine or DMT is present, a compound used by South American Ayahuasqueros in their psychotropic beverage Yage, Hoasca or Ayahuasca. There is a potential danger in attempting to use this vine in such a way as the L-dopa and other compounds may interact negatively with the addition of a Monoamine oxidase inhibitor (MAOi), without which the hallucinogenic compounds are inactive and rapidly metabolized by the digestive system.
Some reports say smoking the leaf has been used as a cannabis substitute. We haven’t tried it so cannot verify. However smoking anything is probably not good for lung health so we don’t recommend it.
The vine is an annual in most subtropical climates ,but may defoliate and reshoot the following spring in the tropics. We have found it very useful for soil building as a companion to fruiting vines. Planted with a passionfruit or granadilla it covers the trellis and improves the soil, yielding a crop of beans in the dry season. By year 2 the passionfruit has scrambled over the trellis using the soil fertility shed by the bean in the dry season, and now the fruit vine dominates the relationship. Its been a very successful exercise in time stacking.
It really is a magic bean! This white seeded form has no irritating hairs on the pods, as do other cultivars.
The Madagascar bean or perennial Lima bean (Phasoleus lunatus) is another tropical backyard wonder. Also living several years it produces masses of tasty lima beans great for salads and soups. Les vigorous than the other beans, but making a great compainion on trellis with vines like Dragon fruit or Pitaya (Hylocereus and selenicereus fruits).
There are several forms of this bean which has been domesticated for several millennia. It was apparently domesticated twice, once in Mexico which yields the smaller sieva bean, and again in Peru which gives us these larger beans. There are few types available in Australia unfortunately, we have located only two.
Lima beans have to be soaked and cooked to remove toxins before eating.
Cowpeas don’t need as much pretreatment and are a tasty bean. This one pictured is an African variety but you will also find in shops beans labelled as product of china that are mostly white, with a black eye, or spot where the embryo is. You can also find a bean in Indonesia called Kacang merah, which is a red cowpea, and we also have seed of a tan variety known as crowder peas from the southern USA.
The cowpea is a marvel crop. Hardy to heat and drought and quite productive. They do well as a forage crop, or a vegetable garden crop.
There is a related variety Vigna unguicullata var sesquipedalis better known as the yard long bean or snake bean. This is bred in asia as a vegetable crop, but there is no reason a backyard breeder couldn’t cross the two and breed a climbing dry bean producer.
Crotalaria species are not edible, in fact they contain toxic alkaloids that harm the liver if directly consumed or consumed via milk contaminated with herbage. What they do do very well however is enhance degraded soils. They fix lots of nitrogen and carbon in their tissues and can be used as mulch, they also trap and eat nematodes, which can seriously harm numerous vegetables and fruit trees especially on sandy soils with low organic matter.
And now we have the trees...
Pongamia pinnata is known as a biodiesel tree. This species native from India all the way to northern Australia is now being grown for its oil rich seed. It can be grown on soils not suitable for cropping and being native provides some familiar habitat.

Samanea saman, the rain tree, is probably my favourite tree in the world. It is a giant, with its broad canopy , and strong trunk and branches. It produces sugar rich pods good as animal fodder that taste like molasses, Its timber is like Walnut, it is cyclone resistant, produces fine honey, and is just beautiful.
One exceptionally large old tree in Venezuela covers and area of 3/4 acre, >3000m2
"During his 1799-1804 travels in the Americas, Alexander von Humboldt encountered a giant Saman tree near Maracay (Venezuela). He measured the circumference of the parasol-shaped crown at 576 ft (about 180.8 m[3]), its diameter at around 190 ft (about 59.6 m), on a trunk at 9 ft (about 2.8 m) in diameter and reaching just 60 ft (nearly 19 m) in height. Humboldt mentioned that the tree was reported to have changed little since the Spanish colonization of Venezuela; he estimated the Saman to be as old as the famous Canary Islands Dragon Tree (Dracaena draco) of Icod de los Vinos on Tenerife.[4]
The tree, called Samán del Guère (transcribed Zamang del Guayre by von Humboldt) still stands today and is a Venezuelan national treasure. Just like the dragon tree on Tenerife, the age of the Saman in Venezuela is rather indeterminate. As von Humboldt's report makes clear, according to local tradition it would be older than 500 years today, which is rather outstanding by the genus' standards. It is certain however than the tree is quite more than 200 years old today."

What is this all about?

Perhaps for many people the Urban landscape is a place of sealed roads, fences, big dogs and green green lawns, a sprawling sea of roofs stretching out where some kind of nature would once have lived.
It is all those things of course, But it is also much more. It just requires a refocus in perception in order to see the forest that remains between the bricks and mortar.

Wherever humans settle we bring changes.
We eliminate some species, while allowing or encouraging others, We greatly modify the hydrology, altering water catchment and infiltration, and we greatly modify the chemistry of Air, soil and water. In short, we change all the key parameters for an ecosystem.

Out amongst the biological deserts of new housing estates, lie older more evolved areas where natural processes have reclaimed space. A walk through any suburb or city will find weeds pushing through pavement, maybe even strangler figs gaining a foothold in some crumbling masonry.

Within these new wild spaces as well as garden space, we are witnessing the birth of novel ecosystems where local and exotic biodiversity are mixing to create hybrid and novel ecologies. These new ecologies are rich in species and extremely interesting as well as functional for human needs.
Understanding these spaces is a necessity as Humanity is set on a course of increasing urbanization that only shows signs of intensification for the forseeable future. More and more land will be converted to suburb as the population increases over the next 40 or so years to 10 billion.

Much of our most useful biodiversity is not in the bush, not on farms, and not in government sponsored seed banks, but actually in our backyards and suburbs peppered through our cities. As it is, these refugia are neither safe nor fully utilized mainly due to a lack of knowledge about its true potential.

This blog is dedicated to opening peoples eyes to the true value of garden biodiversity to enhance the livability of our villages, towns and cities, and in the products and ecosystem services that it provides. By seeking to understand different elements we can understand our own cultures and history, and those of others.

We reside in Australias tropical north, and area with an immense natural biodiversity. ‘Out there’ on the reef, orin some protected piece of forest. This perception perhaps overshadows what lies closer to home and its real value in helping us find a harmonious place in the bigger system.

I hope it may lead to a new understanding and appreciation of the key role that Urban and domestic conservation and integration efforts can have in keeping what we have left of the earths treasures alive through the turbulent century ahead of us.