They are 'capable of more sophisticated behaviour than we imagined', says American bug expert Professor Richard Karban.
His work, which he admits is 'controversial', suggests that plants converse by sending chemical messages through the air, warning of hungry predators.
When a neighbouring plant 'hears' the message, it boosts its defences against grasshoppers, caterpillars and other invaders, he believes.
Professor Karban, of the University of California, believes he has proved that conversations happen between sagebrush bushes - hardy, yellow-flowered shrubs native to the western U.S.
Using scissors, he clipped away at leaves and stems of potted shrubs, damaging them in the same way as a grasshopper would.
He then planted some damaged and undamaged plants in a field and measured levels of predation on their neighbours.
The leaves of the plants with clipped neighbours suffered the least grasshopper damage, the journal Ecology Letters reports.
This is taken to suggest that the damaged plants somehow told their neighbours to shore up their defences.
The professor has yet to identify the airborne chemicals by which the shrubs have a natter.
Source: Dost-dngnai.gov.vn (Daily Mail)