Animal Forage, Food Plants - Perennial, Medicinal Plants, Soil Erosion & Contamination, Water Contaminaton & Loss — by Peter Myers April 5, 2012
You might have seen the cotton growing out west — around St George, Gundiwindi and Dirranbandi in Queensland, Australia, and Moree and Narrabri in NSW.
It’s an annual crop — sown in the spring and harvested in the autumn — grown in flat plains country. The blocks are levelled by laser-guided machinery. However, they’re not quite level: there’s a slight slope from one end of the block to another, which allows flood irrigation.
Huge dams, in a country subject to long droughts, supply irrigation water. But these dams themselves take water from the rivers of the Murray-Darling Basin.
Cotton cultivation began in QLD and NSW in the 1860s when the American Civil War caused shortages in supplies. But that kind of cotton is a recent innovation, less than 200 years old. It was bred in America; ginning and spinning machines are manufactured to suit it. The machinery dictates a preference for fine, long fibres.
Previously, the varieties of cotton grown were perennial, i.e. lasting many years.
Tree Cotton, Gossypium Arboreum, a perennial. and is one of four species of cotton in cultivation; it’s only cultivated commercially in India and Pakistan.
It’s a shrub 2m high and 2m wide, drought tolerant but frost sensitive. Its fibres are coarser and shorter than the annual cotton, so it’s grown less than used be the case. The primrose-yellow flowers are attractive and the shrub, being bushy, would make a good screen.
It comes from Pakistan and India, having been cultivated by the Indus Valley Civilization. A Gossypium thread from Mehrgarh in Pakistan, used to string copper beads, is dated to 5000 BC. Fabrics recovered from the ancient city of Mohenjodaro, dated around 3000 BC, were made from cotton plants closely related to Gossypium Arboreum.
I visited Mohenjodaro, in Pakistan, a few years ago; the name means "city of dead people". It’s the best preserved city of the Indus Valley Civilization, and one of the oldest cities in the world. It used to trade with Sumeria by ship; cotton was probably an export even then, as it was later.
Although Tree Cotton is particularly suited to drylands, it grows well in Childers, Queensland as well. The seed pods open to reveal fluffy cotton-balls with seeds mixed in. Nature’s purpose is to use the fluffy cotton to disperse the seeds.
It was ginned (the seeds removed) and spun by traditional means for thousands of years before mechanized varieties displaced it.
However, Tree Cotton is hardier, more drought-tolerant and more pest-resistant than the new annual varieties.
Short-staple Indian cotton was replaced by long-staple varieties, more suitable for English and American ginning machines. With the change in types of cotton, the methods of cultivation changed and so did the pests. Modern annual varieties are genetically engineered — Roundup-Ready, and even with Bacillus Thuringiensis bred in. But many farmers say that the pesticides and herbicides ruin the soil; and there’s an ongoing debate about irrigation.
Tree Cotton counts as a permaculture crop. Being a tree and adapted to drought, it is deep-rooted and needs much less water than annual varieties — an important factor given the serious water issue of the Murray-Darling Basin. After harvesting, branches or stalks can be fed to animals.
Tree Cotton itself is currently being bred up, to make it more suitable for spinning machines.
In herbal medicine, Gossypium Arboreum is used to increase milk secretion. The Family Herbal, written by John Hill in 1812, recommended the seeds for coughs and "all disorders of the breast and lungs; they cause expectoration, and are very balsamic and astringent." (henriettesherbal.com).Comments (5)