Shield bugs, also known as stink bugs and green vegetable bugs, are common in gardens where they invade plants and use their hypodermic like mouth parts to suck sap. As their stink name suggests they have a powerful unpleasant odour when squashed.
To get rid of shield bugs:
Shield bugs (stink bugs or green vegetable bugs) are difficult to control. Insecticides such as CARBARYL INSECT CONTROL, MALDISON and ORGANIC INSECT CONTROL PYRETHRUM have little effect unless sprayed directly on the insects. SPECTRUM POWDER, being a systemic insecticide will help protect treated plants but as the shield bugs move from plant to plant they may not receive a high enough dose in the sap they suck to kill them.
There is some evidence that squashing one shield bug/stink bug/green vegetable bug releases the pungent odour and that it deters other stink bugs.
Shield bugs are sometimes mistaken for beetles, but they belong to the group of true bugs, the Hemiptera. The shield bug name comes from the shield shaped flat body shape, stink bug name comes from their smell and green vegetable bug comes from the fact that they are often found on ...green vegetables.
Shield bugs feed by sucking sap from a wide range of plants but generally the green shield bug causes no noticeable damage to cultivated plants, even when there are many of them.
Shield bugs are active in early summer when they lay small clusters of eggs on the undersides of leaves. In late summer and autumn they are often seen sitting on plant foliage in the sun. Shield bugs survive winter as adults.
The immature nymphs have a rounded body shape and gradually take on the adult appearance as they develop.
In recent years the green shield bug has become more abundant and widespread in New Zealand.
There are species of shield bugs, which are green brown or yellowish green with reddish markings, that can also be found in gardens.
Common species include: