Melon (Cantaloupe, muskmelon, and watermelon)-Cucumber beetle

Western spotted cucumber beetle (Diabrotica undecimpunctata)
Western striped cucumber beetle (Acalymma trivittatum)

Pest description and crop damage The western spotted cucumber beetle is yellowish green, 0.25 inch long, and has 11 black spots on its wing covers. Mature larvae are white except for the head and last abdominal segment, which are brown. They are about 0.62 inch long. Cucumber beetle adults eat small holes in the leaves and flowers of many crops. Larvae feed on roots and bore into the base of stems.

Management-cultural control

Row covers provide good protection from cucumber beetles, and in addition provide late frost protection and help in moisture retention. Sometimes, the timing of a crop planting can be delayed until after beetles have dispersed and deposited most of their eggs. Delaying planting until warmer weather also gives crops a greater chance of outgrowing beetle injury. Trap crops may be effective in drawing beetles away from the main crop.

Management-chemical control: HOME USE

  • azadirachtin (neem oil)-Some formulations are OMRI-listed for organic use.
  • Beauvaria bassiana-OMRI-listed for organic use.
  • carbaryl
  • cyfluthrin
  • deltamethrin
  • esfenvalerate
  • imidacloprid
  • insecticidal soap-Some formulations OMRI-listed for organic use.
  • malathion
  • permethrin
  • pyrethrins (often combined with other ingredients)-Some formulations are OMRI-listed for organic use.
  • zeta-cypermethrin

Note: Pesticides can injure cucurbits. Be sure foliage is dry at the time of application.

Management-chemical control: COMMERCIAL USE

  • acetamiprid (Assail 30SG) 0.047 to 0.1 lb ai/a. PHI 0 days. REI 12 hr. Retreatment interval 5 days. Do not exceed 5 applications or 0.5 lb ai/a per season.
  • alpha-cypermethrin (Fastac EC) at 0.0175 to 0.025 lb ai/a. PHI 1 day. REI 12 hr. Retreatment interval 7 days. Do not exceed 0.075 lb ai/a per season.
  • bifenthrin (Brigade 2EC) at 0.04 to 0.1 lb ai/a. PHI 3 days. REI 12 hr. Do not exceed 0.3 lb ai/a per season. Do not make more than two applications after bloom. Retreatment interval 7 days.
  • bifenthrin + avermectin (Athena) at 0.048 to 0.116 lb ai/a. PHI 7 days. REI 12 hr. Retreatment interval 7 days. Limit 2 treatments after bloom. Do not exceed 0.056 lb ai/a avermectin or 0.3 lb ai/a bifenthrin per year.
  • bifenthrin + zeta-cypermethrin (Hero) at 0.04 to 0.1 lb ai/a. PHI 3 days. REI 12 hr. Retreatment interval 7 days. Do not exceed 0.4 lb ai/a per season.
  • beta-cyfluthrin (Baythroid XL) at 0.019 to 0.022 lb ai/a. PHI 0 days. REI 12 hr. Retreatment interval 7 days. Do not exceed 0.088 lb ai/a per season.
  • carbaryl (Sevin 4F) at 1 lb ai/a. PHI 3 days. REI 12 hr. Retreatment interval 7 days. Do not exceed 6 lb ai/a per season.
  • chlorantraniliprole/lambda-cyhalothrin (Voliam Xpress) at 0.059 to 0.088 lb ai/a. PHI 1 day. REI 24 hr. Retreatment interval 5 days. Do not exceed 0.18 lb ai of lambda-cyhalothrin or 0.2 lb ai of chlorantraniliprole per acre per growing season.
  • clothianidin (Belay) at 0.05 to 0.067 lb ai/a soil, 0.15 to 0.2 lb ai/a foliar. PHI 7 days foliar, 21 days soil. REI 12 hr. Retreatment interval 7 days. Do not exceed 0.2 lb ai/a per season.
  • cryolite (Kryocide) at 7.7 to 15.4 lb ai/a. PHI 14 days. REI 12 hr. Do not exceed 61.4 lb ai/a per season. Some formulations are OMRI-listed for organic use.
  • cyfluthrin (Tombstone) at 0.038 to 0.044 lb ai/a. PHI 0 days. REI 12 hr. Retreatment interval 7 days. Do not exceed 0.175 lb ai/a per season.
  • deltamethrin (Delta Gold) at 0.018 to 0.028 lb ai/a. PHI 3 days. REI 12 hr. Retreatment interval 3 days. Do not exceed 0.168 lb ai/a per season.
  • diazinon (Diazinon 50W) at 0.25 to 0.75 lb ai/a foliar. PHI 3 days. REI 3 days. Honeydew melons only.
  • dinotefuran (Scorpion 35SL) at 0.05 to 0.18 lb ai/a foliar or 0.23 to 0.27 lb ai/a soil. PHI 1 day foliar; 21 days soil. REI 12 hr. Retreatment interval 7 days. Do not exceed 0.266 lb ai/a foliar or 0.532 lb ai/a soil per season.
  • esfenvalerate (Asana XL) at 0.03 to 0.05 lb ai/a. PHI 3 days. REI 12 hr. Do not exceed 0.25 lb ai/a season.
  • fenpropathrin (Danitol) at 0.2 to 0.3 lb ai/a. PHI 7 days. REI 24 hr. Retreatment interval 7 days. Do not exceed 0.8 lb ai/a per season.
  • gamma-cyhalothrin (Declare) at 0.01 to 0.015 lb ai/a. PHI 1 day. REI 24 hr. Do not exceed 0.09 lb ai/a per season.
  • imidacloprid (Admire Pro) at 0.25 to 0.38 lb ai/a. Soil application only. PHI 21 days. REI 12 hr. Do not exceed 0.38 lb ai/a per application.
  • lambda-cyhalothrin (Warrior II) at 0.02 to 0.03 lb ai/a. PHI 1 day. REI 24 hr. Retreatment interval 5 days. Do not exceed 0.18 lb ai/a per year.
  • lambda-cyhalothrin + thiamethoxam (Endigo ZC) at 0.064 to 0.072 lb ai/a. PHI 1 day. REI 24 hr. Retreatment interval 5 days. Do not exceed 0.18 lb ai/a of lambda-cyhalothrin or 0.172 lb ai/a of thiamethoxam per season.
  • malathion (Fyfanon 8) at 1 to 1.5 lb ai/a. PHI 1 day. REI 12 hr. Limit 4 treatments for watermelon & 2 treatments for all others. Retreatment interval 7 days.
  • methomyl (Lannate SP) at 0.45 to 0.9 lb ai/a. PHI 1 day at 0.45 lb ai/a or 3 days at 0.9 lb ai/a. REI 48 hr. Limit 12 treatments per year. Do not exceed 5.4 lb ai/a per season.
  • novaluron (Rimon) at 0.058 to 0.078 lb ai/a. PHI 1 day. REI 12 hr. Retreatment interval 14 days. Do not exceed 0.234 lb ai/a per season.
  • oxydemeton-methyl (MSR Spray Concentrate) at 0.375 to 0.5 lb ai/a. PHI 21 days. REI 3 days. Limit 1 application per season.
  • permethrin (Loveland Permethrin) at 0.2 lb ai/a. PHI 0 days. REI 12 hr. Retreatment interval 7 days. Do not exceed 1.2 lb ai/a per season watermelons; cantaloupes 0.8 lb ai/a per season.
  • tebuconazole+lambda cyhalothrin (Crossover) at 0.08 to 0.09 lb ai/a. PHI 7 days. REI 24 hr. Do not exceed 0.48 lb ai/a tebuconazole or 0.18 lb ai/a lambda cyhalothrin per season.
  • zeta-cypermethrin (Mustang) at 0.035 to 0.05 lb ai/a. PHI 1 day. REI 12 hr. Retreatment interval 7 days. Do not exceed 0.3 lb ai/a per year.

Note: Pesticides may injure cucurbits. The possibility of injury is less when foliage is dry at time of application.