Zane Nicholls of the Queensland Department of Agriculture, Fisheries and Forestry says that the idea for the initial experiment was the brainchild of a Queensland grower, David Flewell Smith, who some years ago pioneered the practice in collaboration with the support of the Pumicestone Catchment Coordination
Association.
The benefits of this system, says Zane, is that it assists in the retention of the bed height and the integrity of the of the interrows, allowing them to drain the beds, whilst the pineapple develops its own canopy, over 10-12 months.
Tests have shown that the new method can reduce soil erosion in the 17 months from slip planting just prior to harvest, on a 4% slope, from 70 tonnes per ha, to just 16 tonnes per ha.
The companion crops have been specially selected for their properties as Zane explains. "Sorghum and millet are used for Spring and Summer, whilst oats are employed for Autumnal harvesting. The plants were selected for their resistance to nematodes and allelopathic qualities to suppress the emergence of weeds."
The process not only protects the soil from being washed away, it also makes it more tractor proof, meaning that time saving speed can be applied during maintenance.
"Tractor speed can be maintained when addressing the paddock under living mulch as erosion is greatly reduced and machinery is not slower by the formation of ruts and dips."
As well as increasing speed there are other ways in which this method reduces costs.
"The method offsets the need for a pre-emergent herbicide," Zane points out. "and ultimately reduced erosion means less maintenance and sediment traps."
Zane hope the practice will be adopted widely by the areas' pineapple growers.
"Currently there are some highly respected growers promoting the benefits of living mulch, so hopefully within the next couple of years more growers will fit this into their management system."