Though not for lack of trying, Steve Pavich and I failed to land an audience with plant intelligence “guru” Stephano Mancuso in Tuscany last month. As Pavich’s sidekick, I’d less than enthusiastically agreed to visit a weird Tuscan vineyard whose Sangiovese grapes are serenaded 24/7 by strains of Mozart, Hayden and Vivaldi over loudspeakers. Eccentric winemaker Carlo Cignozzi has carried on like this for over a decade, aiming to enhance vineyard health and his vintage’s quality. Nearby University of Florence’s Professor Mancuso’s data indicates plant intelligence.

“Sound exposure has some positive effects on vine growth in the vineyard, especially shoot growth.” His International Laboratory of Plant Neurobiology, which I longed to visit, immerses itself in the controversy swirling around When I managed 700 acres of cannery tomatoes for Newhall Land and Farming forty years ago, dodder (Cuscuta) was Public Enemy No.1 when it came to weeds. We were required to uproot any plant engulfed by that bizarre parasite (a.k.a. devil’s hair, strangleweed), douse it with kerosene and burn it. A leafless, yellow, obligate parasite dodder seedling dies one week after germination if a suitable host is not found. Like a snake charmer’s cobra, a dodder stem gyrates towards prey, employing chemosensory guidance to distinguish favored tomato from wheat. The cadre of international plant scientists profiled in last week’s New Scientist feature, “Roots of Consciousness”, point to acrobatic dodder and other extraordinary botanical species to argue plants are intelligent beings in their own right. Charles Darwin originated the notion, introducing his ‘root-brain’ hypothesis in The Power of Movement in Plants (1880), a bold conjecture
largely ignored until recently.

Inspired by Darwinian insight, Italian, German and Japanese plant physiologists
accumulate evidence for botanical intelligence, focused on the minute ‘transition’ zone just behind every root’s tender apex that senses environmental information, computes same and communicates appropriate response measures to its parent plant. With a single rye plant’s near-15 million roots coordinating information gathered from each, comparisons to humanity’s new-found computer Internet are inevitable. That such elegance orchestrates underfoot, out of sight, belowground has not been helpful to our appreciation. Plant neurobiology champions assert “dumb vegetable” hails from Aristotle’s hierarchical separation of plant and animal life, a premise of classical biology that today interferes with the full blossom of Darwin’s unifying theory of common descent. New Scientist cheekily suggests the world’s vegans might find themselves in a pickle if plants are declared sentient beings. –Tom Willey