Organic Farm Advisory

The Plant & Pest Advisory serves NJ growers by reporting on important pests and recommending responses that are grounded in reproducible trials.

Articles in this section contain information helpful to the NJ commercial organic grower.

Sharing organic practice trial results between land-grant universities is a cost effective way to create a common knowledge base built on the strengths of individual programs. In the sidebar, find institutions with programs in organic agriculture which augment knowledge developed at the Rutgers New Jersey Ag Experiment Station.

Rutgers Cooperative Extension Field Guides: These concise guides help with decision making from pre-planting to harvest. For each crop listed, learn what pests to proactively look for as the season progresses, how to look for them, and when to take action.

Field Guide List

IPM Update 5/22/19

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:

Green Creek   2 Crosswicks   1 Pedricktown   1
Beckett   1 Downer   1 Princeton   1
Blairstown   1 New Egypt   1 Woodstown   1

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.

[Read more…]

Damping-off: Identifying and Controlling Early-Season Damping-off Pathogens

It is extremely important to know which pathogen is causing damping-off problems and which fungicide to properly apply. The key to controlling damping-off is being proactive instead of reactive. Always refer to the fungicide label for crop use, pathogens controlled, and application rates.

Damping-off is caused by a number of important vegetable pathogens and is very common during the spring. Damping-off can kill seedlings before they break the soil line (pre-emergent damping-off) or kill seedlings soon after they emerge (post-emergent damping-off). Common pathogens that cause damping-off include Pythium, Phytophthora, Rhizoctonia and Fusarium spp.

Control of damping-off depends on a number of factors. First, is recognizing the conditions which may be leading to the problem (i.e., weather/greenhouse growing conditions) and second, identifying the pathogen causing the problem.

Conditions Favoring Damping-off

Although all four pathogens are associated with damping-off, the conditions which favor their development are very different. In general, Phytophthora and Pythium are more likely to cause damping-off in cool, wet or overwatered soils that aren’t allowed to dry out due to cloudy weather or cooler temperatures. Conversely, Rhizoctonia and Fusarium are more likely to cause damping-off under warmer, drier conditions especially if plug trays are kept on the dry side to help reduce transplant growth. [Read more…]

IPM Update 5/15/19

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:

Downer   2 Cinnaminson   1 Medford   1
Beckett   1 Elm   1 South Branch   1
Bellemeade   1 Georgetown   1 Woodstown   1

 

[Read more…]

IPM Update 5/08/19

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.

[Read more…]

Allium leaf miner update: 09/20/19

Allium Leaf Miner

Allium leaf miner (ALM) feeding/egglaying scars were detected in chives and scallions near Princeton (Mercer Co.), NJ on Friday of this week.  This indicates that the second (fall) flight of these flies is now underway, and damage is occurring.

Allium leafminer oviposition scars on onion

Photo: Sabrina Tirpak. Allium leafminer oviposition scars on onion

Growers should consider initiating the control method of their choice at this time.  Affected crops include chives, scallions, garlic, onions and leeks.

Floating row covers, kept on until the second flight ends will help minimize access to plants.  Insecticide applications targeting adults may be helpful as well, although frequency of applications is uncertain.  Spinosyn materials (Radiant, Entrust (OMRI approved)), pyrethroids (Mustang Maxx, Warrior), and pyrethrin materials (Pyganic (OMRI approved)), neonicotinoids (Scorpion, Venom) and the insect growth regulator Trigard are labeled for miner control.

Adult activity and observations of feeding will be reported on in the IPM Update as they occur.  At this time, all growers should respond to the second adult generation.  We will attempt to identify the end of the second flight so that growers know when the risk of infestation has abated.

 

 

 

Veg IPM Update: Allium leaf miner 04/10/19

Allium Leaf Miner

Allium leaf miner (ALM) feeding was detected in one commercial planting of chives near Lawrenceville, NJ on Tuesday of this week.  Degree-day accumulations at this site were 46.5, base 50 F as of Tuesday.  Sticky traps at this same site yielded no flies.  Additionally, trap and inspection sites at Milford (Hunterdon Co. (garlic)), and Oldwick (Hunterdon Co. (garlic and chives)), had neither feeding signs nor flies on sticky cards.

Allium leafminer oviposition scars on onion

Photo: Sabrina Tirpak. Allium leafminer oviposition scars on onion

Within the week, another monitoring site near Hackettstown (Warren Co.) will be added.    Reasonable spring weather that we are now experiencing is conducive to the development of the first adult generation.  Growers should consider initiating the control method of their choice at this time.  Affected crops include chives, scallions, garlic, onions and leeks.

Floating row covers, kept on until the first flight ends will help minimize access to plants.  Insecticide applications targeting adults may be helpful as well, although frequency of applications is uncertain.  Spinosyn materials (Radiant, Entrust (OMRI approved)), pyrethroids (Mustang Maxx, Warrior), and pyrethrin materials (Pyganic (OMRI approved)), neonicotinoids (Scorpion, Venom) and the insect growth regulator Trigard are labeled for miner control.

Adult activity and observations of feeding will be reported on in the IPM Update as they occur.  At this time, all growers should respond to the onset of the first adult generation.  We will attempt to identify the end of the first flight so that growers know when the risk of infestation has abated.