Weekly Insect Bytes for September 04, 2015
Posted: September 4, 2015
Brown Marmorated Stink Bug (BMSB)
Although this year pressure from BMSB appears to be somehow lower than during previous years, it is still relatively easy to detect the growing numbers of BMSB. Commercially available BMSB traps are very useful tools to effectively detect and monitor all stages of stink bugs. BMSB monitoring traps placed on trees located on the border of woods as well as traps placed in the first row of orchards, which only sparsely collected stink bugs earlier this season, now are collecting many BMSB nymphs and adults. To better understand the actual BMSB pressure in the entire apple block, it also may be helpful to have at least one trap placed in the middle of the orchard, far away from perceived outside BMSB sources.
Catching stink bug nymphs inside of the orchards means the entire block needs to be protected as BMSB become a “resident pest” and continuous feeding will impact fruit until they are removed from the orchard. An increased number of BMSB is also being observed on sites already harvested such as cherry blocks or early peaches, which did not see any insecticide applications for a long time, and therefore may as well become the source of late season BMSB.
Since not every orchard will experience the same pressure from BMSB, cautious scouting and monitoring of the vegetation surrounding an orchard should be very helpful in deciding if special stink bug control treatment(s) is necessary. It is important to remember the absence of stink bugs during the season, does not guarantee they will not become abundant in the orchard around the harvest time.
The list of effective insecticides options is limited and includes products only with few distinctive modes of action: pyrethroids (IRAC Group 3A): Bifenture (14d PHI) and Brigade (14d PHI) (only WSB formulation, Danitol (14d PHI on pome, 3d PHI on stone fruit), and Warrior (21d PHI on pome, 14d PHI on stone fruit); neonicotinoids (IRAC Group 4A): Actara (35d PHI on pome, 14d PHI on stone fruit)), Assail (7d PHI), Scorpion and Venon (3d PHI); one carbamate product (IRAC Group 1A), Lannate (14d PHI on apple, 4d PHI on peach), and some products including combinations of two different insecticide chemistries such as in Endigo (35d PHI on pome and 14d PHI on stone fruit) or Leverage (7d PHI). While trying to limit the impact of BMSB on fruit, please remember also about seasonal limits for the number of insecticide applications per season.
Tufted Apple Bud Moth (TABM) and Obliquebanded Leafroller (OBLR)
The flights and egg depositions for the second generations of tufted apple bud moth (TABM) and obliquebanded leafroller (OBLR) are nearing their ends for this growing season. If larvae of both species were not previously controlled, they will continue to feed on maturing fruit until harvest. Some late TABM or OBLR moths may still be observed for the next few weeks, however no new generation of adult moths will be active this year.
Codling Moth (CM) and Oriental Fruit Moth (OFM)
The captures of codling moth (CM) and Oriental fruit moth (OFM) adults in pheromone traps are also appear to be on the decline, however only the codling moth will cease its activity within the next few weeks. The fourth generation of OFM is likely to still be present in orchards during September and into October. Site specific monitoring of OFM is the only way to provide accurate information if an additional insecticide application is necessary.
If brown marmorated stink bug also needs to be controlled during September and/or October, most products directed against BMSB should provide at least some limited control of OFM larvae, however the efficacy of most products recommended for BMSB control is not very high against OFM larvae. If specific OFM control is necessary, applications of Altacor or Delegate remain the most effective tools to control this pest.
Seasonal Monitoring Data and Models
For the weekly updates on the seasonal flight activities of most popular pests.
The insect pest control updates presented are for South-central Pennsylvania based on observations in Adams County. To view the insect hatch and trapping data for all major insect pests, please visit the Penn State Fruit Research and Extension Center (FREC) website. For control recommendations, refer to the Insect and Mite Control Toolbox.