Weeding Without Sensorship

weeding without sensorship

This cutter is taking some of the labor out of caring for delicate grape vines.

By Michael Valenti, Senior Editor

Until modern times, vineyards used workers to cut weeds that grew too close to the vines. Chemical defoliants reduced this backbreaking labor, but environmental concerns have precluded their use. Mechanical weeders can do the job, but only if they are equipped with expensive proximity sensors to keep them from damaging delicate vines.

Pellenc S.A. of Pertius, France, specializes in making viniculture equipment and has designed a general-purpose tractor attachment called Tournesol, which removes weeds from vineyards without using chemicals, requiring sensors, or damaging the crops.

The Tournesol assembly is connected to a 132-pound skid that can be hitched to the rear of a tractor. The tractor battery powers the cutting blades as the vehicle proceeds.

Tournesol, the French word for "sunflower," is named for the attachment's twin retractable and articulated blades, which are enclosed by a single yellow, toothed polyurethane cover that resembles a sunflower. The cover-blade assembly is connected to a 132-pound skid that can be side-mounted or hitched to the rear of the tractor. The blades are powered by the tractor's battery.

As the tractor proceeds at 2 to 3 miles per hour between the rows, the periphery of the cover presses lightly against the vines so that the rotating blades can operate at the level of the vine stock without injuring the plant. This eliminates the need for a sensor to avoid the vines.

The yellow plastic cover of the Tournesol attachment lightly presses grape vines out of the way so that the rotating blades can cut weeds.

The heavy skid keeps the cover in close contact with the earth, to prevent stones or soil from being thrown off and to cut down on dust during the summer. The attachment works on flat terrain or slopes, and over different types of soil.

French vineyards, including Chateau La Reze in Rieux Minervois, Chateau Val Janis in Pertius, and Chateau Villepreux in Saint Germain de Puc, use the Tournesol, which Pellenc is marketing to North America through a subsidiary, Pellenc America Inc., in Santa Rosa, Calif. The company also has subsidiaries in Australia, Italy, Slovakia, and Spain.

The Tournesol weeder is the latest product in the family of agricultural machines that founder Roger Pellenc started designing in a shed 28 years ago. Other popular labor-saving Pellenc devices include shake-and-catch tree harvesting machines for olives and nuts and battery-powered electronic pruning shears. French palates agree that the modern technology does not harm the classic bouquet of the vintages.