Navel Orangeworm Control: Looking Back, Looking Forward David Doll UCCE Merced County 11-9-2012
The Many Faces of NOW Why a problem? Invasive pest, host density about 10,000 times greater than original, expansion of acreage closer to native range, almonds in higher temperature environments A True Success Story!
Overview of Lifecycle Higbee and Siegel, 2009
NOW Control Requires a few Considerations CONTROL COVERAGE
Strategy: Population Reduction Population Reduction Strategies: Tree Mummies Ground Mummies Proximity to Pistachios, Figs, Pomegranate Previous Year Damage Harvest Date Peach Twig Borer Chemicals being used
Strategy: Population Reduction AVERAGE # MUMMIES PER TREE # GROWERS AVERAGE % NOW INFESTATION AT HARVEST <2 (0-1.9) 15 1.69 (0-5) >2 (2.6-177) 21 3.53 (0.2-14)
Strategy: Population Reduction New research indicates higher sanitation standard Tree Mummies/Tre e Before Bloom % of Nonpareil Damage at Harvest Ground Mummies/tree Before Bloom % of Nonpareil Damage at Harvest 0 1.63 0-4.9 1.39 0.01-0.49 1.22 4.91-7.9 1.57 0.50-0.69 1.57 7.91-8.9 1.72 0.70-0.79 2.32 9.91-9.0 2.78 0.80-1.75 3.53 >9.1 2.72 >1.75 7.85 Higbee and Siegel, 2009
Overwintering Flight Variety Survival Fritz Nonpareil Monterey Butte Padre 6.92% A 10.00% B 13.00% B 18.00% C 32.09% D
Strategy: Population Reduction So if sanitation is performed to the highest level, I can expect minimal NOW damage? NO doesn t take into account migration!
Strategy: Population Reduction Proximity to pistachios, figs, abandoned almonds Higbee and Siegel, 2009
Adults per 100,000 Nuts Overwintering Flight 50000 Adult emergence from mummies 45000 40000 35000 30000 25000 20000 15000 July Butte Padre 10000 5000 0 1100 1300 1500 1700 1900 2100 Degree days Fahrenheit from January 1
Eggs Overwintering Flight 350 Madera 2009 300 250 200 150 100 July 17 Pisachios A Pistachios B Pistachios C Almonds A Almonds B Almonds C 50 0 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 2200 Degree Days
Overwintering Flight Emergence is inconsistent due - reduced developmental time on mummies Mummies serve as the only food for NOW until hullsplit Earlier hullsplit, shorter time to wait for food source (I.e. Variety of Merced, Independence?) NOW Generates 30-40% faster on new crop nuts (600-800 DD v/s 1056) NOW can feed on tree and ground mummies Number of mummies/tree = % NOW damage
Effects of various insecticides (7/2/99) on NOW infestation (9/15/99) Untreated Water Confirm 2F (16 oz) Dimilin 25W (16 oz) Asana (16 oz) Success (6 oz)) Guthion 50W (4 lb) Brigade (12 oz) Imidan 70W (4 lb) Pounce 3.2 (16 oz) Intrepid (12 oz) Intrepid (14 oz) Intrepid (16 oz) 1.8 1.6 c 1.4 1.2 bc 1 0.8 0.6 0.4 0.2 0 a ab a ab a a a a a Number NOW Infested Nuts/200 a a a a
Strategy: Population Reduction Reduce Risk (Intrepid, Success, Altacor, Belt, etc.) Early Side of Hullsplit/Blank split Pyrethroids (Asana, Pounce), Organophosphates (Imidan) 2-5% Hullsplit All Pesticides: Coverage of nut comes into question Why the difference? Targeted Stage of Pest Pesticide Traits
Persistence of Insecticides Insecticide Eggs Percent Survival Reduction compared to Controls Assail 10 day 200 0.5 98.8% Assail 14 day 200 1.0 97.6% Assail 21 day 200 2.0 95.3% Assail 24 day 600 13.0 69.4% Assail 34 day 200 16.5 61.1% Altacor 10 day 200 0 100.0% Altacor 14 day 200 0 100.0% Altacor 21 day 200 0 100.0% Altacor 24 day 200 1.5 96.5% Altacor 34 day 200 1.0 97.6% Intrepid 10 day 200 1.0 97.6% Intrepid 14 day 200 0.5 98.8% Intrepid 21 day 200 0 100.0% Intrepid 24 day 400 2.5 94.1% Intrepid 34 day 200 0 100.0%
Persistence of Insecticides Brigade in Madera County almonds, August 15, 2007 Day Reduction N 8 95.3% 200 11 98.8% 600 13 97.6% 200 17 89.3% 200 23 90.5% 200 29 91.7% 400
Persistence of Insecticides That may all look good, but keep in mind: 1. It is possible to go too early! 2. NOW egg laying goes up when NP hullsplit starts, but quickly drops off, only to pick back up again for pollinator hullsplit, 3. Damage is highly variable most likely most of the damage comes from hotspots which is then diluted out by clean nuts.
COVERAGE Spray Rig Coverage
COVERAGE Spray Rig Coverage
Conclusion: Speed Doesn t Kill! Spray Rig Coverage COVERAGE Spray Coverage and Effectiveness: 1. Aerofan @ full airflow, 540 PTO RPM @ 100 g/acre with Intrepid, two speeds 1.8 MPH and 2.4 MPH 2. Spray cards measured deposition 3. NOW eggs placed one day after application on nuts, checked for survival (Giles, et al, 2011) Rig Speed Deposition Lower Canopy Deposition Upper Canopy NOW Control Lower Canopy 1.8 MPH 9.2% 5.3% 96.8% 95.8% 2.4 MPH 9.1% 6.7% 95.7% 87.1% NOW Control Upper Canopy
Effect of Hullsplit on Coverage COVERAGE Surface area of almond hull Surface area of almond hull + 20-25% from split Surface area of almond hull + 50-75% from split As nut splits, surface area increases, ability to cover decreases. Implement Bracket Sprays
Week of: 23-Apr 30-Apr 7-May 14-May 21-May 28-May 4-Jun 11-Jun 18-Jun 25-Jun 2-Jul 9-Jul 16-Jul 23-Jul 30-Jul 6-Aug 13-Aug 20-Aug 27-Aug 3-Sep 10-Sep 17-Sep 24-Sep CON TRO L COVER AGE Spray Timing: Population Reduction NOW Trap Counts from 8 orchards near Firebaugh from 2012 25 Timing #2 Timing #3 20 Timing #1 15 Hullsplit NP Hullsplit Poll 10 BIOFIX 5 0
CONTROL COVERAGE Spray Considerations May Sprays are beneficial for NOW control, and reduced risk pesticides prevent flare ups BUT THEY DO NOT REPLACE SANITATION Winter Sanitation Neighboring Crops/Insect Pressure May Spray Population Reduction Bracket Sprays Early side of hull split / 2 weeks later Early Harvest Late Harvesting Varieties Orchard History PTB Damage
CONTROL 2012 Season Thoughts: COVERAGE Warm temps, lack of rain made winter sanitation more difficult, harder to shake, more remaining in the tree, Warmer winter weather favored survivability AND development of larvae, reducing mortality rates, increasing emerging population Mummies did not break down once shaken to the ground, larvae within mummies didn t die, In NSJV, 3 flights occurred, which is expected, supporting lack of sanitation, missed pesticide timings as reasons,
CONTR OL 2012 Season Thoughts: COVERAG E Points to remember: Heat is like fuel to the fire Dry and warm conditions reduce overwintering mortality SANITATION! Human Nature Weekly Updates Provided at www.thealmonddoctor.com