⟼ Native taro could be a new horticultural crop for Far North Queensland
⟼ Native taros can be used for ecological weed management to replace chemical herbicides
We have a wide diversity of native taros (Colocasia esculenta) in Far North Queensland. Cook, Banks and Parkinson recorded collecting and cooking them, especially the leaves as spinach in 1770 on the Endeavour River. Cook wrote in his diary on August 4, 1770, “… but the best greens we found here was the Tarra or Cocco tops called in the West Indias Indian Kale which grow in most Boggy places, these eat as well as or better than spinnage, …” Banks identified them as taro using the botanical name of that time, Arum esculentum, in his diary of June 27, 1770. The name has since been revised to Colocasia esculenta.
Dalrymple, who was the first European to explore and name the Johnstone and Daintree Rivers, in 1873, wrote about a cultivated taro patch next to a village of the indigenous people of the Johnstone.
Taro as Food
Taro production is now a viable industry in Far North Queensland, using the Bun Long variety, originally the best Samoan taro, that they have lost due to taro blight.
It would be good to diversify taro production with some of our Australian native varieties. The tubers are smaller than the introduced cultivars, and some of them have too much oxalic acid to be eaten. It is the same with the leaves. Some native varieties have very high levels of oxalic acid and should not be eaten. These types are not suitable for commercial production. There are low oxalic acid varieties, like the introduced commercial cultivars, and these can make an alternative to spinach. Selecting a good variety of native taro could be a great marketing opportunity for enterprising growers as we should cultivate and eat more native foods.
Taro leaves are eaten in most countries that grow taro for tubers. All taro leaves and tubers contain oxalates. The leaves should be soaked for several hours, and the water drained to remove them before cooking. Leaves with higher levels of oxalates should have the water drained after cooking as well. Oxalates are common in many common green leafy vegetables and can prevent the absorption of minerals such as iron and calcium. Long term exposure to high levels of oxalates can cause kidney damage. Cooking and draining the water reduces the oxalates and increases mineral absorption from these foods.
Taro for Environmental Management and Regeneration
Our native taros could be grown along drains and watercourses as an alternative to spraying them with herbicides. Selective allelopathy is where one plant will suppress unwanted plants without affecting the plants we want to protect. Selective allelopathy is an emerging ecological science and practice where functional biodiversity is used to suppress the plants that are regarded as weeds instead of using tillage or toxic herbicides. It is beginning to be used as an effective ecological form of weed management in agriculture; however, it should be expanded to other ecological systems, especially environmental weed management programs.
Taro is very effective at suppressing para grass (Urochloa mutica) and Singapore daisy (Sphagneticola trilobata) and keeping watercourses from being choked. It tends to easily bend over in floods, and therefore doesn’t block drains. It is a native, so planting these forms of taro will enhance our environment. Native trees, gingers, ferns etc will all grow through native taro, so planting it along watercourses is one of the best ways to reduce weed competition and facilitate the regeneration of our native ecosystems.