Common green capsid is usually most abundant at the edges of orchards next to hedgerows, woodland or alder windbreaks and especially on apple trees with rootstock sucker growths. The tender shoots of such sucker growths are favoured sites for oviposition by adults the previous autumn and usually show signs of infestation first.
- The suckers on trees at the edges of orchards can be inspected in the dormant period for the characteristic bumps indicating where eggs have been inserted into the stem.
- The tips of rootstock sucker growths are often a good indicator of presence or absence of capsids in an orchard.
- They can be inspected on 2 3 occasions for damage from late green cluster to petal fall to determine when egg hatch has started.
- However, best practice is to remove them in winter (see Cultural control).
The best method of assessing levels of common green capsid is by using the beating method, which can detect the pest at low levels before significant damage is done.
- A sample of at least 25 (preferably 50) beats should be made per orchard when the pest assessment is done at the late blossom growth stage of apple.
- If any capsid is collected, beat sampling should continue to confirm the level present.
- The treatment threshold is 3 capsids per 50 beats.
- This method is time-consuming and seldom used in practice.
- As an alternative, the 25 trees should be visually inspected for signs of capsid feeding damage.
- If significant damage is detected, an insecticide treatment should be applied promptly at petal fall.
Work is in progress at East Malling Research and Natural Resources Institute currently to develop a pheromone lure and trap for monitoring common green capsid.