F Murtz wrote:
how can I Zap the stink bugs on the lemon tree ?

Best trick is to use a vacum cleaner early and often. Try a godfrey's
special if you don't have an old one. empty into an old plastic shopping
bag, knot and stomp on it.

Best toxic substance is confidor. They fall dead out of the tree rather
quickly. so do a pile of other beneficial insects for years afterwards.

Note, if they are visiting your neighbourhood enmass(had that 2 years
ago) you need everyone around to take action.