Spray Technology In The Nut Orchard
What will the orchard sprayer look like in 10 years? My crystal ball is a little fuzzy, but here is a review of some current nut orchard challenges and general vineyard/orchard sprayer trends that could help shape the nut crop sprayer of 2020.
Newer, more selective pesticides reduce off-site drift and runoff risks, but up the bar for spray coverage. Many of these new pesticides must be eaten by the pest to kill it. Excellent coverage is therefore needed to deliver effective pest control.
Off-site movement of pesticides is getting more regulatory attention. Air quality, water quality, and health of endangered species such as salmon and steelhead are concerns. Until drift and pesticide runoff are addressed, growers will face a risk of regulatory-based reductions in pesticide use options.
Tower and wrap-around sprayers are becoming more common in grapes and small tree crop growing. These machines deliver the spray from the side or around the tree or vine. The spray is efficiently delivered and spray drift significantly reduced. Unfortunately, many nut crop trees are too tall for wrap-around sprayers and the 12- to-15-foot tall tower machines currently designed and used in grapes, apples, and other trees where the fruit is hand-picked.
But, could tower sprayers be developed for nut tree orchards? Towers help reduce drift and maximize the delivery of spray to the target. Mechanical hedgers and toppers are increasingly used in nut orchards. These machines could be used to cut slots or gaps down a tree row to allow tower sprayers access to tall, dense nut tree canopies. Autosteer systems could keep sprayers tracking down the middle of those slots.
Sensor-triggered sprayers can help reduce drift and pesticide runoff without reducing spray coverage. These units use one or more laser or ultra-sonic sensors per sprayer side to turn on the sprayer when a target is there and off when there is no tree to spray. These units can lower pesticide use per acre compared with “blind” spraying. The layout and age of the orchard can affect the amount of savings. Increased maintenance costs and complaints of temperamental electronics plague some models and hold down adoption of this promising technology.
Electronic Flow Controllers