With the Adaptive Contour Access Path (ACAP) our focus is:
- Enabling improved manual access to the crops.
- Enhancing the soil quality with nitrogen fixing plants – Arachis Pintoi.
- Let the microorganisms do their magic with the soil – Vetiver Grass.
- Reducing erosion on a micro and macro level.
- Slowing down the water flow. Tropical rainfall can be extremely abundant quantity of water in short time.
- High efficiency in food crop production.
- Economically feasible solution (manual labor).
- Creating diverse types of mulch material on site.
Experimental Zone Information
Our test site is located in a area with a elevation is 875-950 meter above mean sea level. Its about 1 Hectare in size. The slope is very steep. Its between 26° and 45° degrees steep! We have a average annual rainfall of 1000-1500 mm per year. The soil consists mainly of – Ultisol – red clay with high mineral content. Within the Köppen-Geiger classification we are in the Tropical rainforest climate. Monthly average rainfall of 170mm, yearly almost 2000mm.
Adaptive Contour Access Path (ACAP)
So basically we are using the different inspirations such as: “Contour Hedgerow Alley Intercropping” and the “SALT-System”. With the primary need to enable access within our crops on a literary VERY steep slope. Thats how we came up with the idea of the Adaptive Contour Access Path (ACAP). Building graduated terraces on the hill with the help of heavy machinery is not always a option, because of the economic cost and the accessibility to the parcel.
So the alternative is to create only the most needed part. In our case that consists in a access path, of 20-40 centimeters width, following vertically the contour elevation within the slope. Now in our case we built it adaptively to the actual contour line. Because its not 100% on contour line. It depends on the procentual steepness of the slope. The steeper the slope, the closer the contour access path should be; conversely, the flatter the slope, the wider the spacing of alleys. To rebalance the difference spacing, we build all the access path adapting slightly up or down the contour lines, depending on the slope steeples.
So every 5-8 meters we build another Adaptive Contour Access Path (ACAP). In between them we have alleys which we use to plant intercropping 5x5m (triangle) permanent producing fruit trees, shrubs and herbs as well as endemic flowers. In a second phase we will plant alternately perennial crops between the permanent annual crops. Because with the spacing of 5×5 meters until the permanent producing fruit trees grow there is plenty of space. Even once those fruit trees are producing there will still be enough space for different crops, on different food forest levels, thinking in 3D farming. Plant short- and medium-term crops between and among permanent crops. Now every now and then there is a fruit tree near to the access path.
In between that space we plant Vetiver grass. Like a contour hedgerow. Once the vetiver grass has grown mature, it can be trimmed down to 25 centimes every 3 month. The left over material is ideal mulching for below the fruit trees. Instead of having to buy organic material the cut off vetiver grass will break down within 30-60 days in a tropical climate with lots of sun and rain.
As ground cover we use Arachis Pintoi. Both elements will help within the system to evolve. The Vetiver roots are very dense and deep and will attract microorganisms and thus enhance the soil quality. The Arachis Pintoi is the perfect tropical climate ground cover processing nitrogen from the air and into the soil in a collaborative relationship with soil organisms. This system is holistic because including the endemic flowers such as Heliconias we provide food (nectar) for the birds and insects such as the different type of stingless bees we have on the farm. They will help with pollination of the fruit flowers and will produce. Obviously existing fruit trees such as Theorboma Cacao and Bitter Mandarin will be part of the system.
At the highest level of the ACAP we will plant giant bamboo (Dencrocalamus Asper) to have a constant production of nitrogen fixing leafs landing on the system slowly running down and breaking down. Also the giant bamboo will help filter water and slow down the water flow. Every bamboo stem will be filtering water and will act as a natural water reservoir in case of a dry period.
ACAP Agroforestry Enhancing Biodiversity
So obviously our goal is to enhance the biodiversity. To increasing our food production security not just in a sustainable way – but in a self-sustainable totally renewable way. By enabling all the players to have a mayor positive impact within the test zone. We have planted about 18 different plants – most of them for food production. Planting spacing in triangles 6x6x6 meters to allow maximizing photosynthesis with an average of 12 hours of sun light. Unlike classic agroforestry / syntropic farming practices we have not planted the fruit trees in rows, but have something more like extreme polyculture with an almost random assembly method.
We picked the fruit species randomly with the exception of never planting twice the same species one bordering the other. This should enhance diversity from within. Time will tell. But not only. Also focusing on enhancing the microorganism and mycorrhiza of the soil on different levels with Vetiver and Arachis Pintoi. Or the endemic insects and tropical stingless bees with a diverse tropical flowers: Heliconias, Hibiscus and two local shrubs that have lots of round yellow flowers.
Fruit Producing Bioadiversity Overview
Alphabetical ordering of the plant diversity and its latin botanical name within the ACAP experimental site at PermaTree:
- Arachis Pintoi (for ground cover)
- Avocado, (Persea americana) 5 different type about 50 plants
- Breadfruit, (Artocarpus altilis)
- Fruti Pan Cacao (Theobroma)
- Cupuacu, (Theobroma Grandiflorum)
- Giant Bamboo (Dendrocalamus Asper)
- Guayusa (Ilex guayusa)
- Heliconias (flower nectar to attract birds and insects. Pollination and pest control)
- Jackfruit (Artocarpus heterophyllus)
- Lemon Grass Membrillo, (Cydonia oblonga)
- Quince Moringa (Moringa oleifera)
- Noni (Morinda citrifolia)
- Rambutan (Nephelium lappaceum)
- Peach-palm, (Bactris gasipaes)
- Palmito, Chonta Rambutan (Nephelium lappaceum)
- Snake fruit, (Bali Salak (Salacca zalacca))
- Soursop (Annona Muricata)
- Starfruit (Carambola)
- Vetiver (Increasing soil microorganism activity)
Vetiver Grass (Chrysopogon zizanioides)
Vetiver tolerance to the extreme climate fluctuations such as prolonged drought, flood, inundation. Waterlogging tolerance extended to 45 days and the withstand temperature range from-100C to 480C. When planting vetiver will grow each dust (like lemon plants), there is no need to take it (bull spread as reeds). Therefore, when it will grow as time grows planted in rows, not grow rampant as weeds. It features not produce seeds, propagated mainly by asexual methods should not fear the spread uncontrollably. Besides, sharp vetiver leaves and roots of aromatic odor, capable of banishing snakes, rats and other rodents.
Additionally thanks to the development of deep and dense root system, vetiver has the ability to absorb toxic in water and soil factors such as heavy metals, chemical plant protection.
Perennial Peanut (Arachis Pintoi)
As a nitrogen fixer the rhizomes of the perennial peanut process nitrogen from the air and into the soil in a collaborative relationship with soil organisms. Thus providing a free alternative to the nitrogen salts of chemical fertilizers. With its extensive root system, rhizoma perennial peanut spreads across the ground as a sod grass would perform.
Arachis Pintoi can be seen as living mulch (ground cover growing around the fruit trees). This is an management strategy that improves soil quality, reduces ground clearing weed maintenance by growing into a dense ground cover.
SALT (Sloping Agricultural Land Technology)
SALT is system on soil conservation and food production, integrating different soil conservation measures in just one setting. Basically, SALT is a method of growing field and permanent crops in 3-meter to 5-meter-wide bands between contoured rows of nitrogen fixing trees. The nitrogen fixing trees are thickly planted in double rows to make hedgerows. When a hedge is 1.5 to 2 meters tall, it is cut down to about 75 centimeters and the cuttings (tops) are placed in alley-ways to serve as organic fertilizers.
SALT is a diversified farming system which can be considered agroforestry since rows of permanent shrubs like coffee, cacao, citrus and other fruit trees are dispersed throughout the farm plot. The strips not occupied by permanent crops, however, are planted alternately to cereals (corn, upland rice, sorghum, etc.) or other crops (sweet potato, melon, pineapple, castor bean, etc.) and legumes (soybean, peanut, etc.). This cyclical cropping provides the farmer some harvest throughout the year.
The greatest problem man will encounter when forest trees are cut extensively without replanting and improper farming of fragile, sloping lands is soil erosion. The erosion of the topsoil. That thin upper crust on the earth’s surface on which man plants his food crops. Is an extremely serious issue in the amazon basin of South America.