Monday, April 7, 2014

Stink Bug

 A wide range of fruit and vegetables, as well as leaves and flowers, are susceptible to the Southern Green Stink bug, nezara viridula. In some countries it is called the green vegetable bug.  

Damage is achieved by inserting their needle-like mouth part into the plant tissue and sucking out the plant juices. Some stink bugs can cause wart-like growths as the plant reacts to the piercing. Although the green color of the pests blends with the foliage making them difficult to find, bugs can be visible feeding in the garden on beans, cabbage, peppers, tomatoes, okra or in the trees on such fruit as mangoes and macadamia nuts. The adults are active fliers, and when disturbed, will fly away or fall towards the ground.

Control is sometimes difficult. Horticultural oils, including Neem oil, work well, but the solution needs to contact the insect. (Read more about Neem on this website.) To spray when the insect is not there will do no good. Oil, as well as soap, is a contact insecticide. Harsher chemicals like Sevin and Orthene will also control this pest. Yet in many areas biological control is effective, and chemical control is seldom necessary. 

In Hawaii, introduced parasites (good guys) are well established and are generally effective. Predators include spiders and the big headed ant. The ants prey upon the eggs and immature stages of the stink bug, taking them back to their nests. The stink bug is so named because of the strong odor emitted from scent glands when disturbed.