April 2019 PIT Group Meetings/Orchard Walks – Fisher (SA) and Merbein (Vic)

The 2019 Autumn Sessions of the PGA PIT Group program was well attended in the two locations (Riverland and Sunraysia) at which the meetings were held.

On Wednesday 10th of April there were 18 growers and presenters at Darin Gladigau’s picturesque riverfront Fisher property located about half-way between Blanchetown and Swan Reach in South Australia.  This round highlighted the feedback mechanism PGA has in place to obtain and deliver information requested by growers – as topics for PIT Group meetings.  Phil Sims had contacted us requesting more information/clarification on male pollinators and percentages of male trees in recent plantings.  Martin Simpfendorfer had also contacted us with regard to apical dominant growth in some of his trees in Paringa. 

Dr. Ben Thomas gave a detailed talk on pollination in pistachio trees and percentages of male trees plated both here and overseas. He talked on the reason for blank nuts and the importance of boron applications at the green tip of bud burst and the various percentage male plantings – from the over-the-top 25% at Darin’s property (most males scheduled for budding over to females), to the 11% of earlier plantings and the now usual 4% of the majority of newer orchards.  One grower was planting as low as 2% and this will be watched with interest in the coming years.  

An interesting aside is that Peter Holt on his property near Robinvale has planted a wind break of male trees completely surrounding his orchard – again to be watched with great interest in future years.Trevor Ranford delivered Chris Joyce’s talk on the preliminary outcomes of the 2018/19 season and harvest.   Crop levels are down 50 to 75% but still the largest off-crop on record processed through APPC.  Fuller results of each individual orchard will be sent to the growers in the near future.  Pistachio Industry Researcher Dr. Subha Abeysinghe delivered a talk on her research program – now underway – developed in conjunction with the Pistachio R&D Committee.  Her talk encompassed blank nuts, how and why they occur which tied in with Ben Thomas’s talk, a long-term trial involving young Kerman trees, increasing zinc absorption in the field and pollination versus nut quality.  

Subha also touched on the introductory trial on the use of polymer technology to increase chill in Pistachio orchards conducted by Dr Shane Phillips from Landmark.  This trial involving only 4 trees as a pre-trial has found that the use of spray applied polymer technology can increase chill portions in the trees ensuring the 59 chill portions required can be reached, thus ensuring good crop set.  This trial is likely to continue.The final speaker at both meetings was Tim Beard who is not only a pistachio grower but a QA assessor as well.  As the purchasers of the majority of the pistachio crop in Australia are the large supermarkets the need for on-farm QA is imperative.

Tim highlighted the programs available and the level of QA the growers should be seeking.   With the development of the new APPC processing facility at Robinvale immanent, the need for all pistachio nuts to come from properties with a QA program is vital.  If the QA program is not signed-off, the nuts will have to be run separately which will incur added costs to the growers and slow the processing down.Following the presentations at each property there were field walks looking at tree pruning methodology, harvest effectiveness and density of males (and pruning of them).

The Merbein meeting at Tim Beard’s property had 19 growers and presenters and followed the same format as the Fisher meeting, with a field walk looking at the pruning/planting methods at the Beard property.  It must be recognized that Tim’s parents Dave and Pam Beard hosted a wonderful lunch with tablecloths and real cutlery instead of the picnic type usually used at the PIT Group BBQs.   

Both PIT Group meetings were started with a BBQ.  Thanks also go to James Simpfendorfer for filming the South Australian session – which will be available via the Industry Videos section of the website once edited.