RESEARCH & EVENTS
Benefits and challenges of high-density planting systems in almonds
It is generally assumed ( and proven widely in many tree crops ) that planting trees at closer spacing presents numerous benefits and some challenges ( see below ). However , the benefits can outweigh the challenges , especially when combined with appropriate management practices and the selection of suitable rootstocks and cultivars for high-density systems .
Benefits
• Precocity ( higher yields earlier )
• Improved light interception
• Improved potential yield
• Improved input efficiencies ( water and nutrients )
• Suitability for mechanisation .
Challenges
• Higher initial capital investment
• Lack of long-term performance data
• Increased management complexity ( trimming and pruning )/ changes to management practices
• Overcrowding .
Peter Jealous , ABA Industry Development Officer ; Dr Roberta De Bei , Senior Scientist at Plant & Food Research ; and Dr Xavier Miarnau , Senior Scientist at IRTA , Spain . Photo : Kellie Hollingworth interception , and tree performance . Overall , the walk will offer a valuable opportunity to understand the complexities of high-density almond production and its potential implications for the Australian almond industry .
Impact for the almond industry : It is still early in the project to be able to confirm definitive research outcomes , however , the trial continues to provide information on the performance of rootstocks and cultivars that could better suit high and ultra-high production systems for Australian conditions . The Australian cultivar ‘ Vela ’ in our trial has outperformed the others especially when grafted on the dwarfing rootstock C6 . From a grower point of view , implications that must be considered relate to :
• Cultivar and rootstock selection : cultivars with more upright , narrow growth habits are more suitable for closer planting as they naturally form narrow canopies . Spreading cultivars might require extra management such as hedging , to optimise their performance . Vigour-controlling rootstocks are also crucial to minimise the need for canopy management and pruning .
• Pruning and training : highdensity orchards demand pruning and training systems that are novel to the Australian industry and that aim to produce narrow tree forms that allow for machinery access and efficient light interception .
• Machinery and harvesting : high-density planting may require specialised machinery , such as narrow tractors and hedgers ( available from other industries or from overseas ), to operate efficiently within the reduced row spacing . High density plantings suit alternative harvesting methods like “ shake and catch ”. Please register online here .
Acknowledgments : We would like to thank Ben Brown , Drew Perry , Sosaia Hala , Jane Finch , Jason Robinson , Vili Ale , James Connolly and the Select Harvests Technical Team for their ongoing support with the trial . This is a project of the National Tree Crop Intensification in Horticulture Program ( AS18000 ) funded through Hort Innovation Frontiers with co-investment from Plant & Food Research , South Australian Research and Development Institute , Hort Innovation using the Almond research and development levy , and contributions from the Australian Government .
industry . australianalmonds . com . au
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