Sweet Corn

European corn borer (ECB) moth captures have decreased somewhat over the past week, and no map will appear in this issue.  The second flight remains very spotty, as is consistent with recent years’ second flights.  Low level feeding has appeared in whorl and pre-tassel corn, but rarely rises to the 12% threshold by itself.  In combination with fall armyworm (FAW) feeding, action thresholds have been exceeded in all areas of the state.

Growers should continue to scout whorl and pre-tassel stage plantings weekly and consider treating when infested plants exceed 12% in a 50 plant sample.  As plantings proceed to the pre-tassel stage, ECB larvae may be found in emerging tassels.  It is a good idea to treat individual plantings as they move into the full tassel/first silk stage one time.  This eliminates any ECB larvae that have emerged with the tassels as they begin to move down the stalk to re-enter near developing ears.

Useful insecticides for this particular application include synthetic pyrethroids (IRAC Grp 3), spinosyns (including OMRI approved Entrust) IRAC Grp 5), and diamides such as Coragen (IRAC Grp 28) or materials such as Besiege which include the active ingredient in Coragen.  Synthetic pyrethroids alone should NOT be used for corn earworm (CEW) protection on silking corn.  Control with these materials is very inconsistent.

The highest nightly black light trap catches of ECB for the week ending 8/14/19 are as follows:

Corn earworm (CEW) moth catches increased late last week in both trap types, then declined somewhat with cooler evening temperatures over the weekend.  The return of warm nights may result in higher CEW activity again.   There were some exceptionally high catches in southern NJ pheromone traps this past week (see blacklight map at left, and pheromone trap map below at right).    There are now economically important populations of this pest throughout the state, and most areas are at extreme risk of crop injury if strict silk spray schedules are not observed.   Red areas on the on the pheromone trap map indicate a 3-day silk spray schedule, while green indicates a 4-5 day silk spray schedule. Blue areas represent a 5-6 day schedule, and white areas are 6-7 day.  There are far fewer CEW pheromone traps than blacklights, and the resulting map has much broader color bands as a result.  It should also be noted that the pheromone traps are much more sensitive than blacklights.  Therefore, the number of moths caught in pheromone traps required to generate a specific spray interval is much higher than the number caught in blacklight traps.   It must be stressed that there is high variability in these catches, and growers should consult with their IPM practitioner on recommended spray schedules.

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Sweet Corn

European corn borer (ECB) moth captures have increased slightly for a second week in parts of the state (see ECB map at left).  The second flight is very weak and spotty, as is consistent with recent years’ second flights.  Limited feeding has appeared in whorl and pre-tassel corn.

Growers should continue to scout whorl and pre-tassel stage plantings weekly and consider treating when infested plants exceed 12% in a 50 plant sample.  As plantings proceed to the pre-tassel stage, ECB larvae may be found in emerging tassels.  It is a good idea to treat individual plantings as they move into the full tassel/first silk stage one time.  This eliminates any ECB larvae that have emerged with the tassels as they begin to move down the stalk to re-enter near developing ears.

Useful insecticides for this particular application include synthetic pyrethroids (IRAC Grp 3), spinosyns (including OMRI approved Entrust) IRAC Grp 5), and diamides such as Coragen (IRAC Grp 28) or materials such as Besiege which include the active ingredient in Coragen.  Synthetic pyrethroids alone should NOT be used for corn earworm (CEW) protection on silking corn.  Control with these materials is very inconsistent.

The highest nightly black light trap catches of ECB for the week ending 8/07/19 are as follows:

Corn earworm (CEW) moth catches are increasing now in blacklight traps in southern and central portions of the state.  Pheromone trap catches have increased as well, with significantly higher catches in southwestern NJ.  There are now economically important populations of this pest throughout the state (see blacklight map at left, and pheromone trap map below at right).   CEW numbers are likely to continue to increase steadily throughout August, with the potential for a dramatic increase in the event of a strong storm system hitting our state.  Red areas on the on the pheromone trap map indicate a 3-day silk spray schedule, while green indicates a 4-5 day silk spray schedule. Blue areas represent a 5-6 day schedule, and white areas are 6-7 day.  There are far fewer CEW pheromone traps than blacklights, and the resulting map has much broader color bands as a result.  It should also be noted that the pheromone traps are much more sensitive than blacklights.  Therefore, the number of moths caught in pheromone traps required to generate a specific spray interval is much higher than the number caught in blacklight traps.   It must be stressed that there is high variability in these catches, and growers should consult with their IPM practitioner on recommended spray schedules.

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Sweet Corn

European corn borer (ECB) moth captures have increased slightly in parts of the southern half of the state (see ECB map at left).  Thus far, the second flight appears to be very weak, as is consistent with recent years’ second flights.  Limited feeding has appeared in whorl and pre-tassel corn.

Growers should continue to scout whorl and pre-tassel stage plantings weekly and consider treating when infested plants exceed 12% in a 50 plant sample.  As plantings proceed to the pre-tassel stage, ECB larvae may be found in emerging tassels.  It is a good idea to treat individual plantings as they move into the full tassel/first silk stage one time.  This eliminates any ECB larvae that have emerged with the tassels as they begin to move down the stalk to re-enter near developing ears.

Useful insecticides for this particular application include synthetic pyrethroids (IRAC Grp 3), spinosyns (including OMRI approved Entrust) IRAC Grp 5), and diamides such as Coragen (IRAC Grp 28) or materials such as Besiege which include the active ingredient in Coragen.  Synthetic pyrethroids alone should NOT be used for corn earworm (CEW) protection on silking corn.  Control with these materials is very inconsistent.

The highest nightly black light trap catches of ECB for the week ending 7/31/19 are as follows:

Corn earworm (CEW) moth catches have increased somewhat in blacklight traps in the southern half of the state, while pheromone traps have remained fairly steady with the exception of Cape May County, where a significant increase occurred (see blacklight map at left, and pheromone trap map below at right).   Some coastal trap catches from states to our south are showing signs of increase, but overall, catches remain highly variable.  While none of these catches indicate that a large scale migratory influx is underway, the trend has been gradual increase with scattered hot-spots.   Red areas on the on the pheromone trap map indicate a 3-day silk spray schedule, while green indicates a 4-5 day silk spray schedule. Blue areas represent a 5-6 day schedule, and white areas are 6-7 day.  There are far fewer CEW pheromone traps than blacklights, and the resulting map has much broader color bands as a result.  It should also be noted that the pheromone traps are much more sensitive than blacklights.  Therefore, the number of moths caught in pheromone traps required to generate a specific spray interval is much higher than the number caught in blacklight traps.   It must be stressed that there is high variability in these catches, and growers should consult with their IPM practitioner on recommended spray schedules.

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Sweet Corn

European corn borer (ECB) moth captures have again declined to extremely low numbers, and no map will appear in this edition.  Thus far, the second flight appears to be very weak, as is consistent with recent years’ second flights.  Limited feeding should appear within 1-2 weeks, but may be obscured by fall armyworm (FAW) feeding by that time.

Growers should continue to scout whorl and pre-tassel stage plantings weekly and consider treating when infested plants exceed 12% in a 50 plant sample.  As plantings proceed to the pre-tassel stage, ECB larvae may be found in emerging tassels.  It is a good idea to treat individual plantings as they move into the full tassel/first silk stage one time.  This eliminates any ECB larvae that have emerged with the tassels as they begin to move down the stalk to re-enter near developing ears.

Useful insecticides for this particular application include synthetic pyrethroids (IRAC Grp 3), spinosyns (including OMRI approved Entrust) IRAC Grp 5), and diamides such as Coragen (IRAC Grp 28) or materials such as Besiege which include the active ingredient in Coragen.  Synthetic pyrethroids alone should NOT be used for corn earworm (CEW) protection on silking corn.  Control with these materials is very inconsistent.

The highest nightly black light trap catches of ECB for the week ending 7/24/19 are as follows:

Corn earworm (CEW) moth catches have remained fairly steady (but highly variable) in blacklight traps, while pheromone traps have registered significant increases in some areas over the past week (see blacklight map at left, and pheromone trap map below at right).   Catches from North Carolina remain highly variable, while Delaware’s catches are similar to our southern NJ catches while also exhibiting wide variability.  While none of these catches indicate that a large scale migratory influx is underway, the trend has been gradual increase with scattered hot-spots.   Red areas on the on the pheromone trap map indicate a 3-day silk spray schedule, while green indicates a 4-5 day silk spray schedule. Blue areas represent a 5-6 day schedule, and white areas are 6-7 day.  There are far fewer CEW pheromone traps than blacklights, and the resulting map has much broader color bands as a result.  It should also be noted that the pheromone traps are much more sensitive than blacklights.  Therefore, the number of moths caught in pheromone traps required to generate a specific spray interval is much higher than the number caught in blacklight traps.   It must be stressed that there is high variability in these catches, and growers should consult with their IPM practitioner on recommended spray schedules.

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Sweet Corn

There have been very modest increases in European corn borer (ECB) moth captures this past week.  Most measurable catches occurred in central and northwestern Burlington County (see ECB map at left). These individuals  represent a second flight.  The next 2 weeks will give us an indication of how significant this flight will be.  In recent years, the second and later flights have been very low.  New feeding should appear within 2 weeks, but may be obscured by fall armyworm (FAW) feeding by that time.

Growers should continue to scout whorl and pre-tassel stage plantings weekly and consider treating when infested plants exceed 12% in a 50 plant sample.  As plantings proceed to the pre-tassel stage, ECB larvae may be found in emerging tassels.  It is a good idea to treat individual plantings as they move into the full tassel/first silk stage one time.  This eliminates any ECB larvae that have emerged with the tassels as they begin to move down the stalk to re-enter near developing ears.

Useful insecticides for this particular application include synthetic pyrethroids (IRAC Grp 3), spinosyns (including OMRI approved Entrust) IRAC Grp 5), and diamides such as Coragen (IRAC Grp 28) or materials such as Besiege which include the active ingredient in Coragen.  Synthetic pyrethroids alone should NOT be used for corn earworm (CEW) protection on silking corn.  Control with these materials is very inconsistent.

The highest nightly trap catches of ECB for the week ending 7/17/19 are as follows:

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Sweet Corn

Very low numbers of European corn borer (ECB) moths were again captured this past week, but not enough to generate a map image.  These individuals likely represent the onset of a second flight.  New feeding should occur after an increase in adults.

Growers should continue to scout whorl and pre-tassel stage plantings weekly and consider treating when infested plants exceed 12% in a 50 plant sample.  As plantings proceed to the pre-tassel stage, ECB larvae may be found in emerging tassels.  It is a good idea to treat individual plantings as they move into the full tassel/first silk stage one time.  This eliminates any ECB larvae that have emerged with the tassels as they begin to move down the stalk to re-enter near developing ears.

Useful insecticides for this particular application include synthetic pyrethroids (IRAC Grp 3), spinosyns (including OMRI approved Entrust) IRAC Grp 5), and diamides such as Coragen (IRAC Grp 28) or materials such as Besiege which include the active ingredient in Coragen.  Synthetic pyrethroids alone should NOT be used for corn earworm (CEW) protection on silking corn.  Control with these materials is very inconsistent.

The highest nightly trap catches of ECB for the week ending 7/10/19 are as follows:

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