After the session at the trial block, we visited Peter Barrowclough’s orchard of 3000 trees, planted in 2008. The main variety is Whiteheart with Alex and MDB pollenisers.
The block already had shelter when Peter planted it, and is now close to full canopy cover. The polliniser layout is every 3rd tree in every 4th row, which gives 3 rows of Whiteheart then one row of mixed Whiteheart/pollenisers. Everyone present with the same sort of layout agreed that the practical disadvantages far outweigh any benefit from optimising the pollen distribution. The pollenisers have different growth habits to Whiteheart and the polliniser nuts generally need to be sorted out from the main harvest (except for occasional years where the different nutfall timings are in favour of the grower).
Peter’s highest yield has been 5 tonnes but that has declined over recent years as the canopy closes in. He has also noticed an increase in the number of blanks, which is likely also a result of lack of light. Clive suggested a possible path forward might be to cut back every 2nd tree in adjacent Whiteheart rows in an alternating pattern.
Peter also described some of his orchard management practices and we had a chance to see some of his equipment.
- Soil moisture is monitored via an Aquaflex system. When moisture falls below the trigger threshold, Peter applies 6mm of water on alternate days via micro-sprinklers. Late in the season, it’s a difficult balance to apply enough water to keep the leaves on the trees (out of the way of harvest) but not so much that the soil is too wet to harvest from.
- Yara Mila complex fertiliser is applied regularly and has resulted in vigorous growth.
- No copper or insecticides are used.
- Buster is used to control suckers, at a rate of 2% (2 litres per 100l of water). This is the concentration recommended by Stephen Brailsford when the orchard was established, but other growers use lower concentrations with good control (1.3% or even the label rate of 0.75%). An important consideration when using Buster is that as a contact herbicide, thorough coverage is required. Some growers also use Glyphosate to control suckers with good success and no obvious ill effects on the main tree.
- Peter’s Jolly 1800 harvester, mounted on the front of a John Deere 4720, harvests each row in 5 minutes. The harvester has an arrangement of augurs, screens and blowers to ensure nuts are picked up but most debris is left in the orchard.
The collected nuts are fed through a Chianchia cleaner and, via a conveyor (for visual inspection to remove any remaining debris) to a dryer. A diesel heater with air exchange and internal augur ensures fast, even drying.