Trialling drones and tractors for cost-effective revegetation (1 May 2019)

A drone with the capacity to plant an entire hectare of trees in less than 20 minutes is just one of the revegetation methods set to be trialled by the new CRDC Landcare Tech-Innovations 2021 project.

Led by Dr Rhiannon Smith from the University of New England, in collaboration with ecosystem restoration experts, UK-based BioCarbon Engineering, the research aims to improve capacity for cost-effective revegetation on cotton farms by trialling new and improved direct seeding technologies using drones and tractors.

“Your average cotton farm is in a semi-arid region and occurs on a very heavy clay soil,” Dr Smith explained.

“Clay soil dries out very quickly and combined with variability in rainfall and high temperatures, you get a huge natural impediment to getting native vegetation established.”

“What this project is doing is investigating a number of different innovative technologies including drones as an alternative to traditional expensive and time-consuming revegetation methods such as tube stock planting or traditional direct seeding by tractors that can only be done when the soil is quite dry so the tractors don’t get bogged.”

“In contrast, drones come into their own if you’ve got a saturated soil that’s more likely to allow seeds to germinate and get established. Here we’re talking about floodplain species that naturally flower and seed after a flood event.”

“We’re planning on replicating natural conditions, so we’re more likely to get successful establishment of native vegetation around cotton farms.”

Dr Smith said the drones being trialled have been developed by BioCarbon Engineering using technology built at Oxford University.

“BioCarbon Engineering have developed a drone that has a 15 kilogram payload with a modified air rifle on it,” Dr Smith said.

“These drones can shoot seeds into the ground at 40 metres per second while hovering two metres above the ground, all controlled by someone sitting in the airconditioned comfort of their ute. Usually we would require a tree planting team to achieve large-scale revegetation”

The seeds being ejected by the modified air rifle are no regular seeds either.

“We’ll be using water soluble seed capsules that are pumped full of seeds, fertiliser, microbial amendments and anything else that’s required to get seeds germinated and established,” Dr Smith said.

“The seeds are protected in that capsule until there’s enough moisture at the site to break down the capsule and allow the seeds to germinate and establish.”

Dr Smith said her job now is to prove the concept of the planting methodology on cotton farms.

“Growers understand the range of ecosystem services provided by native vegetation in the landscape. For example, natural pest control services provided by birds and bats that live in native vegetation deliver direct economic benefits to cotton production,” Dr Smith said.

“Biodiversity and native vegetation allow growers to perhaps diversify their income streams as well. For example,  carbon sequestration may be an attractive option as an alternative income stream for unproductive areas of the farm.”

“The benefits of biodiversity and native vegetation for sustainable agriculture in general are immense and go a long way in supporting healthy, vibrant environments for cotton growing communities.”

Under the National Landcare Program’s Smart Farming Partnership initiative, CRDC secured a $1.3 million grant to implement the three-year Cotton Landcare Tech-Innovations 2021 project.

Australian researchers from the University of New England and the Queensland University of Technology will lead project activities, in collaboration with international researchers from BioCarbon Engineering in the UK and University College, London.

CRDC’s Cotton Landcare Tech-Innovations 2021 project will focus on four key research areas; innovation, technology, biodiversity and collaboration.

For more information, visit the Cotton Landcare Tech-Innovations 2021 page, or listen to Dr Smith's interview with ABC