Providing an optimum environment to sugarcane is essential to increase yields. As crops last several years (typically 5~6 years), it can be difficult if not impossible to alter soil conditions during that period.
This long lasting productivity can be attained thanks to the practice of ratooning(i.e. harvesting while leaving the root and part of the stem) for future crops.
Sugar cane is characterized by a large root system, ranging in depth, which makes it able to colonize the land sloped very strongly. This strong root system also helps to hold the soil in place, protecting the field from the impact of flooding and gravity. The soils conducive to its development are those that allow these root systems, offering enough depth and soil aeration whithout being too resistant to root penetration.Regarding soil conditions, sugarcane is generally regarded as a highly tolerant plant.
Sugarcane is not planted from seed but rather from stalks. Stalks are produced from nursery grown canes which were cut into pieces. Usually, each stalk are cut to have three buds. Most of the sugarcane is panted on one of the following ways :
- Creole fashion: Stalks with three buds are inserted into the soil following a 45° angle. The upper bud is left free from the soil and will be in charge of making fresh shoots may the lower two buds be stifled by the ground.
- flat : Stalks are laid flat on a furrow bottom. This way being cheaper and more efficient, it tends to be more and more used worldwide.
Main tasks required to care after a sugarcane field are:
- Irrigation : Sugarcane requires a lot of water to grow as most C4 plants usually do. In dry climates or during periods of drought, it may be necessary to supplement the natural supply of water (rain, dew, humidity ,...) by watering or irrigation.
- Drainage : Stagnating water can smother the plant's roots amd belate the cane's grow. Drainage usually requires creating devices to remove stagnating water from flat lands.
- Weeding : Weeds tend to restrict young shoots from getting as much light and water they require. Weeds can also become hosts for cane's diseases and parasites. When the cane grow, its fast pace and high reaching helps it to fight efficiently again weeds.
- Burning: Depending on the common local practices or the land specificities, the field is sometimes set on fire prior to harvesting. The fire destroy the weeds and the occasional snakes that might been lurking in the canes.
- Diseases: monitoring canes may help detecting diseases affecting plantations. Main measures include implementing a quarantine treatment or destructing measures in contaminated areas for the rest of the plantation is not affected
Sugarcane economic role has already been described. Its diseases have therefore been a major subject of study and research institues have spawned worldwide. Perhaps the most known is the Bureau Of Sugar Experiment Stations which have been created in 1900 in the Australian state of Queensland.
Sugarcane diseases can be classified into three main categories, depending on the disease's origins :
- Fungi (mildew, smut, pineapple disease, red rot, back stripe, brown spot, ...)
- Phytoplasmae : (gumming disease, leaf scald, mottled stripe, ratoon stunting disease, ...)
- Viruses : (mosaic, dwarf, streak disease, ...)
Main disease fighting methods are:
- Planting only disease free stalks obtained through selection or disinfectant spraying.
- Thoroughly cleaning fields and tools (esp. blades).
- Pest control as many bacterial and viral diseases are transmitted by insects.
- Creating disease resistant crops. This way of fighting the sugar cane diseases is quite a recent one as it requires creating hybrids, a technic invented during the 20th century.
Animals and pests
Insects can also be a threat for sugar cane crops. Depending on the caused damage, they can be subdivisied int the following categories:
- Roots : mostly white grubs (beetle larva form) but also grasshoppers, termites and nematodes (worms) attacking the roots by burrowing or feeding.
- Leaves and stems are targeted by biting insects (leafhoppers, sharpshooters, scale insects, ...). In addition to the damage caused to stems and leaves, those insect can also infect the cane with bacterial or viral diseases.
- Borers (various kind of moth larvae), drill short tunnels of various shape in the stem. Those tunnels are generally found close to the stem surface and young plants are more prone to be attacked than older ones. Borers are the older and probably the most dangerous threat to sugarcane crops.
- The leaf-eating caterpillars can also cause damage to sugarcane plants but those damages are usually not so important, compared to other threats.
Pest control is achieved by the following means:
- Chemicals (pesticides such as D.D.T.)
- Introducing parasitoids. This method is primarly used against borers. Tachinidae are commonly used parasites. Female tachinidae yield their eggs at the borer tunnel entrance. The larvae progress in the tunnel and get into the borer body. The tachinida larva then develops inside the borer and ultimately kills it.
- Creating sugarcane crops less prone to insect attack or more resilient to the damages caused by insects.
Rats can also be an important threat to plantations, all the more if a colony settles in a field. Methods used are conventional rodent control ones (anticoagulant or poisonous baits, traps, ...).