Identification and Control of Orchard Ants David Doll Farm Advisor Merced County Yolo/Solano County Almond Day
Ants Found Within the Orchard Non-Problematic Orchard Ants: • Argentine Ant (Linepithemahumile) • Native Gray Ant (Formica species) • Pyramid Ant (Doymymexinsanus) • Bicolored Pyramid Ant (Doymymex bicolor) • Small Honey Ant (Prenolepis impairs) • California Harvester Ant (Pogonomyrmexcalifornicus) • Thief Ant (Solenopsismolesta) • Pest Ants of Almonds: • Pavement Ant (Tetramoriumcaespitum) • Southern Fire Ant (Solenopsisxyloni) • Red Imported Fire Ant (Solenopsisinvicta)
Almond Ant Damage Very Little Damage reported on Huller Grade Sheets!
Pest Ants of Almonds: Mounds -Out of full sun -Weeds present at entrance -In areas of moisture
Pest Ants of Almonds: Fire Ants Southern Fire Ant v/s Red Imported Fire Ant
Non-Problematic Orchard Ants Bi-Colored Pyramid Red Harvester Ant
Non-Problematic Orchard Ants Argentine Ant Native Gray Ant
Scouting for Ants • May – Early June • Further South Scout earlier in May • “Stomp Test” or “Let them bite you test” • Colonies located 3’ apart count as different county • Five 1000’ square foot sections
Ant Damage Control • Cultural Controls • Delay Harvest and Pick-up Almonds as Quick as Possible • Longer on the ground = more damage • Baits (Esteem, Clinch, and Extinguish) • Baits are brought back to the nest and affect whole colony • Apply baits before the heat of the summer – when ants are closer to the surface • Do not use within 24 hours after an irrigation, 48 hours before • Conventional Sprays (Lorsban) • Only kills foraging workers
Finding the balance… - Longer in the tree, possibly more NOW damage - Longer on the ground, possibly more ant damage - Need to know populations present!
Any Questions? Weekly Updates about almond production can be found at “The Almond Doctor,” www.thealmonddoctor.com