Tag Archives: Insecticides

Corn Earworm and Late Planted Sweet Corn

Corn earworm pressure often increases as we head into September. With turbulent weather patterns originating in the Gulf of Mexico, flights of airborne moths are generally quite high.  As the tradewinds mix with the cooler air of the great lakes, these high populations are dropped into Southern Ontario.  Any sweet corn at the green silk stage is highly susceptible to corn earworm infestation.

For earworm control, cover green silks with an insecticide such as Coragen or Voliam Express.  Avoid insecticides from the pyrethroid family.  Corn earworm are known to be resistant to the pyrethroids.  Lannate TNG is a good rotational partner for Coragen and Voliam Express.

Heliothis trap for corn earworm monitoring

Time to Scout for Asparagus Beetles

Asparagus beetle activity is on the rise. The adult beetles hide in soil cracks or underneath residue during the heat of the day.  Egg laying is often the most obvious sign of their activity. The presence of eggs on the harvest spears, may affect marketability. On young fern, heavy amounts of larval feeding has a negative impact on growth and development.

As harvest concludes, scout plantings regularly as the spears begin to elongate and develop a full canopy of fern. Spray thresholds are as follows:

Eggs:   2 /10 spears with eggs
Larvae:   50% of plants with   larvae OR 10% Defoliation
Adults:   5-10% of   plants infested

If controls are required during the harvest season, play close attention to the pre-harvest intervals.  Products with a 24-hr pre-harvest interval include: malathion (Malathion 85E), cypermethrin (Mako, Upside 2.5 EC), and acetamiprid (Assail 70WP).

Spotted Asparagus Beetle (Hannah Stevens, retired MSU)
Common asparagus beetle (Hannah Stevens, retired MSU)

Lassoing Loopers: why you NEED to care about caterpillar control

Adapted from ONfloriculture by Sarah Jandricic, Greenhouse Floriculture IPM Specialist, OMAFRA

This article was originally written for the floriculture industry, but I have adapted it, with permission, as an awareness article for vegetable growers. — Janice

Know which looper species this is? Are you SURE? If not, keep reading, as some species could get your shipments detained at the border. Photo: Steve Hatch, Bugwood.org.
Know which looper species this is? Are you SURE? If not, keep reading, as some species could get your shipments detained at the border. Photo: Steve Hatch, Bugwood.org.

At this point, most field vegetable growers are focussed on getting the crops in and juggling early season field activities. If you’re thinking about caterpillars right now, it would probably be black cutworm.  But recent alerts put out by the United States Department of Agriculture (USDA), bring a new emphasis to caterpillar control.  Read on to understand what’s happening, and — for those with US customers — how to control occasional pests like cabbage looper, and avoid potential issues at the border. Continue reading Lassoing Loopers: why you NEED to care about caterpillar control

Growers requested to complete survey on neonic use

The Canadian Horticultural Council (CHC) is currently preparing a response to PMRA’s proposed re-evaluation decision on imidacloprid and other neonicotinoid use (example products: Admire, Intercept, Genesis, Gaucho). To ensure an effective response, CHC requests feedback from growers on their use of these pesticides. Each survey takes about 15-20 minutes to complete, and can be saved and continued at any time prior to the deadline. Submission deadline: February 6, 2017. Continue reading Growers requested to complete survey on neonic use

How to assess spray coverage in vegetable crops

From sprayers101.com. By Jason Deveau, OMAFRA.

Water sensitive paperSprayer operators recognize the importance of matching their sprayer settings to the crop to optimize efficacy. For example, spraying a protective fungicide in field tomato should require a different approach from spraying a locally systemic insecticide in staked peppers. Knowing this, many operators make ad hoc changes and then wait to “see if it worked”. A process is required that empowers the operator to make systematic changes to their program and assess coverage immediately. Continue reading How to assess spray coverage in vegetable crops

Scouting for pepper weevil in field peppers

Pepper weevil is a pest that is likely unfamiliar to most Ontario field pepper growers. It has been found in Ontario previously (https://onvegetables.com/2010/06/01/pepper-weevil/) and there have been reports of its presence in 2016. As it can be a very serious pest of peppers, it is advisable for all pepper growers to monitor for the pest in their crop. Pepper weevil can affect both field and greenhouse pepper crops, but this article will focus on scouting and management in the field.

The insect

  • Adults are small weevils, 2-3.5 mm in length (Figures 1 and 2).
  • Difficult to detect the pepper weevil adults through crop scouting if it is present at low levels
    (unless using pheromone traps).
  • Eggs are laid in the fruit wall, leaving a dimpled scar (Figure 3).
  • Larvae grow and develop inside the pepper fruit; pupae form inside the fruit (Figure 4).
  • New adults create an exit hole and leave the fruit.
Figure 1: Pepper weevil adult on pepper flower bud
Figure 1: Pepper weevil adult on pepper flower bud

Continue reading Scouting for pepper weevil in field peppers

Got cabbage maggots? We’re interested!

Laura Stortz, OMAFRA / University of Guelph USEL student; Denise Beaton, OMAFRA Crop Protection Program Lead; Hannah Fraser, OMAFRA Entomology Program Lead (Hort)

The Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) is collecting Cabbage Maggot larvae and pupae this summer as part of a national survey. We need grower cooperators for this survey! The goals of this survey are:

  1. To better understand the fly species responsible for damage to Brassicae vegetable crops.
    The larval stage of the Delia radicum fly species is thought to be the main culprit attacking Brassicae vegetable crops; however, there could be other species at play.
  2. Test for pesticide resistance in the fly species.
    Cabbage maggot is showing resistance to Lorsban (chlorpyrifos). This study’s results could lead to more efficient use of insecticides and support research on alternative control options.

Background: Continue reading Got cabbage maggots? We’re interested!