Beet Armyworm (BAW) Advisory

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Beet Armyworm (BAW) Advisory

For Scallion & Onion Farmers in Manchester & Southern St Elizabeth

November 2019


The recent rains have facilitated increased plant growth (scallion, onion etc., and weeds) – providing more food source for the beet armyworm and as such we are experiencing an increase in the pest population:

Farmers are advised to ACT EARLY and:


  • Intensify the monitoring of crops at least twice a week or every three days
  • Utilize the pheromone traps as a monitoring tool to detect the early arrival of the migrating beet armyworm adults (or bats)
  • Utilize bug zappers at night in New Forest Manchester, and in Southfield and Junction in St Elizabeth
  • Monitor for the early detection of the egg sacs often deposited near the tip of leaves
  • Newly hatched worms will emerge within three days. This is critical as this is the most vulnerable and susceptible stage where cultural and chemical strategies are to be applied. Handpicking is recommended where practical.
  • When spraying, choose least toxic, bio-rational insecticides, to minimize negative impact on natural enemies (or farmers friends). Apply pesticides as necessary targeting early instars. Use Bio-rational insecticides by targeting young worms (1st - 2nd instars)
  • Older worms are hardier, insecticidal treatment are less effective and worms are less exposed to chemicals and natural enemies, since they reside inside the leaves
  • Effectiveness of the treatments may be enhanced in small plots by clipping off the leaf tips prior to application, especially if the older beet armyworms have entered the leaves.
  • Manage all weeds within and surrounding the fields which may harbour the pest especially grasses around these fields during the rainy period as they may become an additional host for the pest.
  • Ensure that scallion crop is harvested and sold at maturity and not left in the field due to marketing issues. Unmanaged or abandoned plants encourage the build-up of beet armyworm populations.



  • Follow advisories and text messages sent out by RADA immediately; Delays will only be harmful by supporting an increase in the population and increase the risk of crop damage
  • Contact your RADA extension officer if you are noticing an increase in beet armyworm population in your field.
  • Community involvement will play a big role in successful management of the beet armyworm – work together to get pest numbers down in neighbouring fields.


For further information please contact your nearest RADA office 1-888-ASK-RADA or the Research and Development Division, Plant Protection Unit (Bodles Research Station) in St. Catherine.

RADA (toll free) 1-888-ASK RADA (275-7232
RADA Manchester - 962-0479/0477
RADA St Elizabeth – 966-2285/2232/2872
Bodles Research Station, Plant Protection Unit (R&DD, MICAF) – 745-2960/745-2956