Sweet Corn
European corn borer (ECB) catches are very low, and with cooler evening temperatures through the weekend, not enough ECB have been captured to register a map image. This flight has been extremely low and very spotty. ECB feeding in NJ sweet corn plantings is nearly non-existent now. What remains has been overshadowed by fall armyworm (FAW) feeding. Check 5 plants each in 10 random locations for a 50 plant sample. Look for “shot-hole” injury, and consider treating when the number of infested (from ECB or FAW) plants in a 50 plant sample exceeds 12%. As infested plants proceed to the pre-tassel stage, live larvae and damage may be found in the emerging tassels. Once plants hit full tassel, ECB larvae will move downward on the stalk and re-enter the plant near the area where ears are forming. This can result in direct injury to the ear. Growers should consider an insecticide application at the full tassel stage to target ECB larvae as they migrate downward. This application can eliminate larvae that have escaped any earlier insecticide applications. [Read more…]
Search Results for: corn borer
Veg IPM Update: Week Ending 9/06/17
Veg IPM Update: Week Ending 8/30/17
Sweet Corn
European corn borer (ECB) catches have remained very low, but blacklight traps have captured just enough to register a map image (see map at left). This flight has been extremely low and very spotty. ECB feeding in NJ sweet corn plantings remains very low, and has been largely obscured by fall armyworm (FAW) feeding. Check 5 plants each in 10 random locations for a 50 plant sample. Look for “shot-hole” injury, and consider treating when the number of infested (from ECB or FAW) plants in a 50 plant sample exceeds 12%. As infested plants proceed to the pre-tassel stage, live larvae and damage may be found in the emerging tassels. Once plants hit full tassel, ECB larvae will move downward on the stalk and re-enter the plant near the area where ears are forming. This can result in direct injury to the ear. Growers should consider an insecticide application at the full tassel stage to target ECB larvae as they migrate downward. This application can eliminate larvae that have escaped any earlier insecticide applications. [Read more…]
Veg IPM Update: Week Ending 8/23/17
Sweet Corn
European corn borer (ECB) catches have again declined to levels that do not permit a map image. This flight has been very sporadic. ECB feeding in NJ sweet corn plantings is very low, and has been largely obscured by fall armyworm (FAW) feeding. Check 5 plants each in 10 random locations for a 50 plant sample. Look for “shot-hole” injury, and consider treating when the number of infested (from ECB or FAW) plants in a 50 plant sample exceeds 12%. As infested plants proceed to the pre-tassel stage, live larvae and damage may be found in the emerging tassels. Once plants hit full tassel, ECB larvae will move downward on the stalk and re-enter the plant near the area where ears are forming. This can result in direct injury to the ear. Growers should consider an insecticide application at the full tassel stage to target ECB larvae as they migrate downward. This application can eliminate larvae that have escaped any earlier insecticide applications. [Read more…]
Veg IPM Update: Week Ending 8/16/17
Sweet Corn
European corn borer (ECB) catches have been largely contained to Hunterdon and Somerset counties this past week (see ECB map at left). This flight has been very sporadic. ECB feeding in NJ sweet corn plantings is very low, and has been largely obscured by fall armyworm (FAW) feeding. Check 5 plants each in 10 random locations for a 50 plant sample. Look for “shot-hole” injury, and consider treating when the number of infested (from ECB or FAW) plants in a 50 plant sample exceeds 12%. As infested plants proceed to the pre-tassel stage, live larvae and damage may be found in the emerging tassels. Once plants hit full tassel, ECB larvae will move downward on the stalk and re-enter the plant near the area where ears are forming. This can result in direct injury to the ear. Growers should consider an insecticide application at the full tassel stage to target ECB larvae as they migrate downward. This application can eliminate larvae that have escaped any earlier insecticide applications. [Read more…]
Vegetable IPM Update: Week Ending 8/9/2017
Note: Due to technical difficulties, only sweet corn related maps and information will appear in this edition of the IPM Update. We hope to resume full coverage next week.
Kris Holmstrom and Joe Ingerson-Mahar
Sweet Corn
European corn borer (ECB) adult numbers have again subsided, and no map will appear here. As with last year, the second flight of ECB in New Jersey is low and sporadic. While we are beginning to see limited feeding from this pest, it is relatively insignificant compared to fall armyworm (FAW) feeding that is now occurring on whorl stage sweet corn. Insecticide applications should be made when 12% or more plants exhibit signs of ECB and/or FAW feeding. FAW is, and will remain the dominant pest of vegetative stages of sweet corn for the remainder of the season. Damage is extensive in the southern most counties, while it has increased only slightly over the past week in central and northern NJ.
Corn earworm (CEW) catches have gotten slightly more consistent in blacklight traps around the southern half of the state, while pheromone trap catches have risen dramatically in some areas (see CEW blacklight and pheromone trap maps). Growers now treating silking sweet corn should adhere to silk spray schedules to limit damage.
The following are recommended silk spray schedules by region:
South – 3 days
Central – 4-5 days
North – 5-6 days
With frequent rains, the incidence of rust is increasing in some sweet corn plantings. Additionally, northern corn leaf blight has also been discovered in the northern counties. These diseases can be economically significant, particularly if they first appear in whorl stage plants. Should this situation occur, growers need to consider fungicide applications to limit damage. See the latest Commercial Vegetable Production Recommendations for suitable fungicides on this crop. 
Veg IPM Update: Week Ending 8/02/17
Sweet Corn
European corn borer (ECB) catches remain low, but are occurring in some locations with greater intensity (see ECB map at left). This is the early part of the second flight. In recent years, this flight has been very sporadic. ECB feeding in NJ sweet corn plantings is still nearly non-existent at this time, but should appear again within a week, although it may be obscured by fall armyworm (FAW) feeding. Check 5 plants each in 10 random locations for a 50 plant sample. Look for “shot-hole” injury, and consider treating when the number of infested (from ECB or FAW) plants in a 50 plant sample exceeds 12%. As infested plants proceed to the pre-tassel stage, live larvae and damage may be found in the emerging tassels. Once plants hit full tassel, ECB larvae will move downward on the stalk and re-enter the plant near the area where ears are forming. This can result in direct injury to the ear. Growers should consider an insecticide application at the full tassel stage to target ECB larvae as they migrate downward. This application can eliminate larvae that have escaped any earlier insecticide applications. [Read more…]
