Agriculture. La silphie, a “green” culture that reassures local residents

With the non-treatment zones (ZNT), cultivators are prohibited from treating at the edges of houses. Despite these regulations, sprayers systematically attract the glare of local residents. In Tracy-sur-Mer (Calvados), Benoît Comet will no longer have this kind of problem. The dairy farmer sowed silphie perfoliée in a plot of 2.8 hectares, near a residential area.

No phytosanitary treatment

This perennial plant from the asteraceae family (like the sunflower), native to North America, does not require any phytosanitary treatment or synthetic fertilizers. Just a herbicide (one pass) after a single semi. And presto, it’s gone for several years. Fertilization comes from livestock effluents. “The silphia grows back for at least fifteen years …”, says Benoît Comet. With some exceptions (in culture alone), it is not harvested the first year. The breeder sowed it in May 2021, associated with corn that he has just ensiled.

In these lands of deep silt, l he new plant has taken root well under the corn. It will be harvested like alfalfa from next year. The two to three cuts of silage, which will be carried out in May, July and September, will be included in the ration of the eighty dairy cows on the farm. At the rate of three to four kilograms per day of dry matter in the trough.

Like Benoit Comet, twelve other farmers from the Creully cooperative have embarked on this unique crop for the region. On 43 hectares. ” Given the climate change, we are working to secure fodder ”, explains Jean-Philippe Chenault, agronomy manager of the cooperative. In the “drying” sectors of Calvados and Manche, corn crops have been disappointing in the recent past. Silphia has the advantage of being resistant to water stress and frost. “It even withstands two months underwater”, reports Benoït Pasquet, animal nutrition manager at Coop de Creully. No wonder that cultivation has developed a lot in the Vosges with higher yields than corn (thirteen tonnes of dry matter compared to nine tonnes).

Honey plant too

In Normandy, the first results are encouraging. Protein levels exceed 15% and yields are expected to be over fifteen tonnes of dry matter per hectare. Enough to quickly amortize the cost of implantation of € 1,700 per hectare. “There is a little dirt this year but the silphia suffocates all the weeds after two years”, explains Benoit Comet.

This “homemade” protein reduces the cost of nitrogen correctors, such as soybeans, the prices of which are currently soaring. “It is possible, for example, to reduce the proportion of corn on a farm from 40 to 35 ha and devote 5 ha to silphia”, says Benoït Pasquet. “ We plan to double the surfaces next year “, predicts Jean-Philippe Chenault.

Honey plant that flowers (yellow and goes up to 3.50 m!) from June to September, the silphia can also supply methanizers. Via a single cut after flowering. As in eastern France and Germany. Bees love it at a time (late summer) when their food is scarce. “That’s 150 kg of honey per hectare! “ announces Amédée Perrein, boss of ADN, the seed supplier. The agricultural merchant of the Vosges, custodian of the Silphie France brand, indicates that the silphie is now established “In sixty-eight French departments, over more than 3,000 hectares. ”

Amédée Perrein expects, in 2022, on 10,000 additional hectares and developments in Canada, Italy, Belgium and Switzerland. “Since the last two droughts, we have been crumbling under the demands of farmers who can no longer produce good corn yields in regions such as the north-east, the Vosges, the Côte d’Or or the Rhône valley. “

– .