Search Results for: corn borer

Sweet Corn

 IPM Personnel are still capturing low numbers of European corn borer (ECB) moths, although even these captures are fairly sporadic, and extremely low in the northern counties (see map at left).  Despite this, single digit feeding percentages were found on Middlesex county whorl stage corn on Wednesday of this week.  It is likely that ECB injury has occurred on early plantings in most areas, although it is probably very light.  Early plantings grown under plastic will be at risk first, followed by the first bare ground plantings.   Growers should begin scouting whorl corn for injury.

Sweet corn emerging tassel with ECB droppings.
Photo: Kris Holmstrom

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 (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 5/29/19 are as follows:

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Sweet Corn

Low numbers of European corn borer (ECB) moths continue to be captured in a few traps (see map at left).  Several cold nights may have suppressed the first flight of the season, although declining ECB populations due to transgenic corn may play a part in the low catches.  Early plantings grown under plastic will be at risk first, followed by the first bare ground plantings.   Through the central counties, a few early corn plantings have reached the whorl stage.  Growers should begin scouting whorl corn for injury.  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.

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

Several corn earworm (CEW) individuals have been captured in blacklight traps this week.  Catches occurred at Port Colden in Warren County, Matawan in Monmouth County and Woodstown in Salem County.  These individuals likely represent a limited overwintered population to our south, and arrived on the southerly breezes that occurred over the weekend and early this week.  There is little threat from these CEW at this time.

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Sweet Corn

Most of the IPM Program black light trap network is now operational in New Jersey.   To date, no corn earworm (CEW) have been captured.  However, low numbers of European corn borer (ECB) moths are now appearing in a number of traps (see map at left).  This is the onset of the first flight of the season.  As yet, most corn is too young to support an infestation, although early plantings grown under plastic will be at risk first.   As numbers increase and corn plantings progress into the whorl stage, growers should begin scouting for injury.  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.

The highest nightly trap catches of ECB for the week ending 5/15/19 are as follows:

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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 have begun to monitor traps.  To date, no corn earworm (CEW) have been captured.  The low numbers of European corn borer (ECB) moths that have been caught do not allow us to produce a map image.  As numbers increase, look for population maps of ECB, CEW and CEW catches from pheromone traps in this weekly publication.  The Vegetable IPM Program is expanding the use of CEW pheromone traps to include central and northern counties this year.  The resulting full-state maps will include interpretive information.

The highest nightly trap catches of ECB for the week ending 5/08/19 are as follows:

Georgetown   1              Woodstown   1

Hillsborough   1

European corn borer egg mass on a pepper leaf.

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Note:  This is the final weekly edition of the Vegetable IPM Update for 2018.  Further updates may be published in response to specific pest threats. 

Sweet Corn

European corn borer (ECB) moth catches remain low.     There will be no map in this edition.   [Read more…]