Design science is at the root of any definition of permaculture or put simply, permaculture is design science. — Bill Mollison
Permaculture is a design/holistic/integrative science, whereas the mainstream/academic science is reductionist — that is, to understand how things work, scientists break a system and study the tiny parts.
Nevertheless, permaculture can benefit from reductionist science, to find relevant knowledge and new design ideas, but above all to gain some academic arguments to demonstrate the validity and legitimacy of its principles and techniques.
This is an article which shows some of the links I’ve found between scientific articles published in national and international journals, while searching facts and numbers to help me design my property. During the process, some ideas just popped, so I included them to make the article a “live performance” of the usefulness of lurking in the scientific jungle sometimes.
So, my property is 1.5 ha (2 acres) in a temperate climate, and the most important characteristic is that it has quite a steep slope, oriented toward the sun. A couple of goats have eroded parts of the land in the past. Some of the land is flat, fertile, and in front of the house — so I guess we’ve found the Zone 1 garden plot! Characteristics of the rest of the land make it a good candidate for reforestation, so I plan to create a food forest on it, with its complimentary animals (us and poultry).
Permaculture is a search for harmony in the process of positioning living or inanimate things in such a way that they can meet their natural needs, and perform their natural behavior. The efficiency of the system is met in using these behaviors and any output in an integrated way.
A good way to know to requirements of a species, like a chicken, for example, is to check how their wild counterparts live. A paper from K. C. Klasing studies the food consumed by red jungle fowls. It is so interesting I’m quoting it extensively:
Foods of plant origin that are frequently consumed include fruits and berries from trees and
herbaceous shrubs, seeds from a variety of plants especially bamboo seeds when available, nuts, young shoots of bamboo and other grasses, leaves, petals, and tubers. When near villages and agriculture, they eat readily available rice, millet, and vetches, but they are not reported to especially pursue these foods. Foods of animal origin that are frequently consumed are termites and their eggs and pupae, winged ants and their eggs and pupae, earthworms, roaches, grasshoppers, spiders, moths and their caterpillars, beetles and their grubs, small crabs, snails, centipedes, and lizards. Invertebrates are obtained by scratching at leaf litter in the forest. Insect communities in elephant droppings may be an important food source in many locations(1).
The permaculture approach of a food/fodder forest for poultry based on perennials is confirmed, and the current mainstream approach of feeding chickens with annual grains is somewhat dismissed.
How to grow a food forest? The permaculture way to do this is to interplant fruit/nut trees with pioneer trees, as seen in nature. I like this because a lot of pioneer trees are wind resistant, produce food for chickens, stabilize steep or eroded slopes, are not destroyed by deer and add fertility. What a program! Just a few examples:
- Seabuckthorn (Hippophae rhamnoides) helps to infiltrate rain water, with a coefficient of only 0-3% at 50 mm daily precipitation and with a near five fold more accumulated infiltration than farmland after a 30 minute rainfall (2). After feeding seabuckthron, “the rate of laying eggs and the number of eggs increased 10.3% and 28.1% for 2-year-old hens. The weight of chickens increased 5.74% and that of hens 7.81% after feeding with leaves and fruit residues after 56 days”(3). It reduces the decrease of meat flavor during regular temperature and heat stress(4). The fruits are packed with proteins and vitamins, and are edible.
- Autumn Olive (Elaeagnus Umbellata) is often used as a nurse crop. Works on walnuts (Juglans spp.) interplanted with autumn olives show that the nitrogen-fixing shrubs increase the growth of black walnuts by 85% after 9 years(5); increase the amount of nitrogen, phosphorus, potassium, calcium, and magnesium in their leaves(6); decrease by two times the amount of juglone (a chemical component secreted by walnut that affects growth of non-tolerant species) in the soil(7); reshape black walnuts(8) and decrease anthracnose(9). Autumn olive fruits are also edible, and eaten by chickens (though no scientists bothered to study this aspect).
Potential other pioneer species include pea shrub (Caragana arborescens) and Black locust (Robinia pseudoaccacia). Black walnuts, helped by autumn olives, are also edible for humans and poultry (once cracked). They also benefit from poultry manure when young (10). When one adds mulberries (Morus spp.), tolerant to juglone(11) with fruits relatively rich in proteins, well balanced in essential amino acids requirements for poultry, with high protein leaves that can be included in chicken pellets(14), and a long bearing season and self harvested fruit by poultry, one begins to see the potential of a food and forest garden for humans and poultry, as expressed by Mollison and Holmgren in their books!
The first citation about red jungle fowls reminds me about bamboo. What about growing bamboo near your poultry house, where the nitrogen tends to accumulate, so it can furnish cover, wind protection, young shoots and seeds? Maybe chickens could provide a natural way to control bamboo expansion? In regards to seed, bamboo doesn’t make seeds often (some species take 120 years!). Luckily for us, Daniel H. Janzen asked himself why bamboo waits so long to flower(12), and wrote an article in which he listed several species of bamboo with the number of years between flowering years. This might be helpful for designing fodder systems based on bamboo seeds for poultry? Ok, it’s just musing, but I include it to show how scientific articles can expand creativity during the design process.
Forest gardens not only provide food, but also cover from aerial predators, thus allowing poultry to range more and farther. As a study showed:
It was clear from this comparison between houses that the amount of tree cover in the range areas was a good predictor of the number of birds that would come outside the house.[…] Despite being the most distant habitat, trees and bushes
were consistently chosen over short grass or short grass near a fence, and open short grass was the least preferred habitat despite not being the most distant(13).
Chickens are also beneficial to trees. A comprehensive study made about the interactions between chickens and mulberry showed that chickens in a mulberry plot (at a density of 450 per ha) killed 90% of weeds in seven months(14). Domestic fowls were also good at pest control, including the Apriona japonica Tomson, a pest of mulberry.
We’ve seen some good trees for nuts and fruits (among many, many more), but as we’ve seen earlier, wild chickens consume a lot of insects (and not a lot of roasted soybeans or dried fish-meal) in the wild. A number of scientific papers show links between poultry and
insects. A promising insect is the larvae of black soldier fly (Hermetia illucens), which can reduce poultry manure by half, and 500g of flies per year could be raised from the manure of one laying hen. Black soldier fly larvae have 42% crude protein on a dry weight basis, making it a good food for poultry and could replace soybean or fish-meal(15).
We have just seen a little of the kind of knowledge and connections that can be studied and learnt in a permaculture system. Permaculture is science, and science, even when very fragmented, can be weaved into a more complex pattern. It is also the work of permaculturists to tap into this useful and overlooked resource.
- Poultry Nutrition: A Comparative Approach, K. C. Klasing.J. Appl. Poult. Res. Summer, 2005 vol. 14 no. 2 426-436.
- Seabuckthorn (Hippophae sp. L.): New crop opportunity for biodiversity conservation in cold arid Trans-Himalayas, Somen Acharya, Tsering Stobdan, Shashi Bala Singh Source: Journal of Soil and Water Conservation Vol: 9 Issue: 3 pp: 201.
- Evaluation of nutrient value of seabuckthorn in north China, Jian-zhong Hu and Xiao-feng Guo. Forestry Studies in China, Volume 8, Number 1, 50-52.
- Effect of Sea Buckthorn Leaves on Inosine Monophosphate and Adenylosuccinatelyase Gene Expression in Broilers during Heat Stress, W Zhao, X Chen, C Yan, H Liu, Z Zhang, P Wang. Asian-Aust. J. Anim. Sci. Vol. 25, No. 1 : 92 – 97.
- Autumn-Olive as a Nurse Plant for Black Walnut David T. Funk, Richard C. Schlesinger and Felix Ponder, Jr. Botanical Gazette Vol. 140.
- Effect of autumn-olive on the mineral composition of black walnut leaves, Felix Ponder. Communications in Soil Science and Plant Analysis, Vol. 14, Iss. 12, 2008
- Juglone concentration in soil beneath black walnut interplanted with nitrogen-fixing species, Felix Ponder and Shawky H. Tadros. Journal of Chemical Ecology , Volume 11, Number 7, 937-942
- Early growth and form of common walnut (Juglans regia L.) in mixture with tree and shrub nurse species in southern England, J.R. Clark, G.E. Hemery and P.S. Savill. Forestry (2008) 81 (5): 631-644.
- Destruction of Gnomnoia leptostyla perithecia on Juglansniga leaves by microarthropodes associated with E. umbellata Litter, K. J. Kessler. Mycologia 82, 387–390.
- Using Poultry Litter in Black Walnut Nutrient Management, Felix Ponder, Jr., James E. Jones, and Rita Mueller. Journal of Plant Nutrition, 28: 1355–1364, 2005.
- A review of suitable companion crops for black walnut, Robert Scott, William C. Sullivan. Agroforest Syst (2007) 71:185–193.
- Why Bamboos Wait So Long to Flower, D H Janzen. Annual Review of Ecology and Systematics (1976) Volume: 7, Issue: 1, Publisher: JSTOR, Pages: 347-391.
- What makes free-range broiler chickens range? In situ measurement of habitat preference, Marian Stamp Dawkins, Paul A Cook, Mark J Whittingham, Katherine A Mansell, Amy E Harper. Animal Behaviour,Volume 66, Issue 1, July 2003, Pages 151–160.
- Uchino, K., Watanabe, M. Ishida, H. & Sato, A. 1988. Effect of guinea fowls raised in a mulberry garden. Bulletin of Chiba Prefectural Sericulture Experiment Station, 6: 1-10 (in Japanese).
- A value added manure management system using the black soldier fly, D. Craig Sheppard, G. Larry Newton. Bioresource Technology, Volume 50, Issue 3, 1994, Pages 275–279.