Sweet Corn

Attention sweet corn growers!  Please take a few moments to complete this survey.  Rutgers IPM personnel expect to participate in grant funded research guided by grower responses.  See the brief description below. Thank you for your help!

Corn Earworm Management in Sweet Corn Needs Assessment Survey

Dr. Kelly Hamby, Associate Professor/Extension Specialist with the Department of Entomology at University of Maryland, is leading a team of researchers, including Rutgers IPM staff, who have developed a survey to prioritize research and extension efforts for improving corn earworm management in sweet corn throughout the Northeast. We appreciate your participation in this survey and will use results to develop a grant proposal to try to get federal funding to address these needs.

Survey link: https://ume.qualtrics.com/jfe/form/SV_9vRh1xHnDp4KEaa

Low numbers of European corn borer (ECB) moths continue to be captured in parts of the state.  Cool temperatures over the past weekend have likely suppressed activity, and warmer weather in the upcoming week may trigger a modest rebound.  The highest adult activity is currently around the Atlantic-Camden County border (see map at right).  Whorl corn is the primary target for egg laying, and injury as high as 16% of plants infested has been found up to northern Monmouth County this week.  Feeding levels should rise over the next 3 weeks.

Look for the characteristic “shot-hole” type of feeding (photo below at right) 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 (see photo at left).  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 or Vantacor (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 6/02/21 are as follows:

[Read more…]

Sweet Corn

European corn borer (ECB) moths are now being captured in parts of the state.  As yet, numbers are low, and the next 7-10 days will likely tell whether this flight will be of any significant size.  Current “hot spots” are around Salem County and southern Hunterdon into Mercer and Ocean counties (see map at right).  Whorl corn is the primary target for egg laying, but as yet, scouts have reported no signs of feeding injury.  We expect to encounter feeding over the next week.  .

Look for the characteristic “shot-hole” type of feeding (photo below at right) 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 (see photo at left).  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 or Vantacor (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 5/26/21 are as follows:

[Read more…]

Sweet Corn

The black light trap network in New Jersey is now operational.  To date, one corn earworm (CEW) at Green Creek (Cape May County), and several European corn borer (ECB) moths have been captured.  As numbers increase, look for population maps of ECB, CEW, brown marmorated stink bug (BMSB) and CEW catches from pheromone traps in this weekly publication.  The resulting full-state maps will include interpretive information.

The highest nightly trap catches of ECB for the week ending 5/19/21 are as follows:

[Read more…]

Sweet Corn

IPM Program personnel have re-established the black light trap network in New Jersey.  With very cool evening temperatures, no corn earworm (CEW) and very few European corn borer (ECB) moths have been captured.  As numbers increase, look for population maps of ECB, CEW, brown marmorated stink bug (BMSB) and CEW catches from pheromone traps in this weekly publication.  The resulting full-state maps will include interpretive information.

The highest nightly trap catches of ECB for the week ending 5/12/21 are as follows:

Jones Island   1

Milltown   1

Woodstown   1

[Read more…]

Sweet Corn

IPM Program personnel are currently finishing deployment of the black light trap network in New Jersey.  At present, we are approximately 80% operational and will begin to monitor traps by the end of this week.  We do not anticipate corn earworm (CEW) or  European corn borer (ECB) moths for some time yet, but as numbers increase, look for population maps of ECB, CEW, brown marmorated stink bug (BMSB) and CEW catches from pheromone traps in this weekly publication.  The resulting full-state maps will include interpretive information.

[Read more…]

Note:  This will be the final regular edition of the Vegetable IPM Update for 2020.  We will post alerts should special pest situations arise.

Sweet Corn

Corn earworm (CEW) moth captures continue to decline, although with temporary increases on warm nights.    Growers should consider this pest to still be at moderate population levels in the state, with higher risk during stretches of warmer nights.   The current population poses a threat to silking corn.  Blue areas on this map (see map at left)   represent a 4-5-day spray schedule.  The low catches in the southern county blacklight traps are contradicted somewhat by the pheromone trap network.   For further information on CEW activity, see pheromone trap information below.

The highest nightly trap catches of CEW in black light traps for the week ending 10/07/20 are as follows:

[Read more…]