SQUASH BUGS
COMMON NAME: Squash Bug, Stink Bug
SCIENTIFIC NAME: Anasa tristis, Order-Hemiptera (True Bugs), Family-Coreidae
DESCRIPTION: ADULTS - Rather large bugs up to about an inch long and brownish black in color. The head is very narrow and the abdomen as wide or wider than the "shoulders". Has the distinctive triangle shape in the center back. EGGS - Eggs are reddish-gold and laid in clusters on the host foliage. NYMPH - Looks like a wingless adult with reddish legs and head and a green to brown body.
LIFE CYCLE: The adults emerge from overwintering and seek cucurbits to feed upon. Eggs are laid on the foliage and soon the nymphs hatch and begin feeding. They develop into adults and there are often two generations per year in the southern states. The adults overwinter in dark, moist, protected places such as under garden debris, straw mulch or wood on the ground.
HOST PLANTS: All vine crops are at risk, especially cucumbers, melons, pumpkins, and squash.
TIME OF YEAR: All the warm months, especially July through September.
WHAT TO LOOK FOR: The adults should be fairly easy to spot because they are so large and dark. Look for them near the ground or where the plant "branches". Suspect a problem if your plant looks wilted even after a good watering. Leaves may become crisp and brown at the edges. Check the leaves for the conspicuous clumps of red eggs or young bug is near the center vein.
PROBLEMS AND DAMAGE: When feeding the Squash Bug injects a toxin that causes infested plants to wilt and eventually die. Other diseases will often infect the weakened plant. The plant will cease to produce blossoms and developing fruit will die.
CULTURAL CONTROLS: Don't give the Squash Bug any hiding places. .Be diligent in your weeding and clean away any wilted, broken, or diseased foliage. Agricultural fleece covering can protect susceptible young plants until it has to be removed for pollination or heat.. Rotate your crops. Plant early or late to avoid peak infestation times.
COMPANION PLANTING AND REPELLENTS: The bugs are reportedly repelled by plantings of marigolds, nasturtiums, radishes, or tansy.
TRAPS: Adults may hide under boards during the day. Check and kill any found.
MECHANICAL CONTROLS: Squash the clusters of eggs when you find them. The adults can inflict a painful "bite" if handled and will also emit a terrible odor. Use a stick or rock to smash them when hand picking. A hard water spray or soap-n-water spray will force them off the plant, but they probably will come back.
NATURAL CONTROLS: Tachinid flies, birds, frogs, and turtles are natural enemies.
BIOLOGICAL INSECTICIDES: Try brewing cedar chips in warm water for a "tea" to spray on the infested plants. Pyrethrum will give a quick knockdown but the large adults may recover. Insecticidal soap may work. Sabadilla or Rotenone is recommended for large populations. Nicotine will also work but can be a dangerous substance to use.
CHEMICAL CONTROLS: Please consult the Agricultural Extension Agent or a Master Gardener Volunteer for current recommendations (Tel. 458-1104 in Sierra Vista or 384-3594 in Willcox). A whatever you use, FOLLOW LABEL DIRECTIONS EXACTLY and take the necessary precautions to protect yourself, other humans, non-target animals, and the environment.