As from 1927, the members of the Grenoble walnut growers’ Federation had shaken branches with a big stick; walnuts were hand-collected, cleaned and sorted carefully before being sized, according to the requirements of the Federation Administration Board. Most of the time, walnuts were gathered by the communal trade association and delivered in “ox-pulled” carts or in “car-trucks” to the Federation, the head office of which being located in l’Albenc (small village close to Vinay). At their arrival, bags were weighed in front of a trade association representative and an Administration Board member. The Federation paid in cash these representatives, who gave the money back to the farmers of their area. This practice lasted until the sixties, when cheques replaced bank notes. In the 1970s only, growers were remunerated directly and individually, meaning they had to open their own bank account.

In 1929, walnuts were delivered to Tullins factory. Bad-looking walnuts were put aside by trained female sorters. Afterwards, walnuts went through mechanical washers, then in the dryer before being sized mechanically. Finally, they were packed in bags, ranging from 50kg to 500g, before being shipped.

In 1932, 900 tons of walnuts were harvested, among which 625 tons were sold in shell, 75 tons as fresh and 200 tons as kernels.

The biggest crops were registered in 1952, 1972, 1982 and 2006. Between 1990 and 2000, production had risen from 1600 to 3300 tons.

In 2008, Coopenoix collected 6000 tons, among which 250 tons of fresh walnuts, 5900 tons of dried walnuts and 150 tons of shelled walnuts.

Besides the extension of crop areas (from Saint-Marcellin to Moirans in 1936), that stretches today from the Drôme to the Savoie départements, the regular increase of production can also be explained by manuring, quality treatments and tree trimming.

In 1924, we used to plant 40 to 60 trees per hectare and it took fifteen years for them to grow into an adult tree suitable for harvesting. Nowadays, more than 100 trees are planted on a hectare, producing walnuts after 5 years. Since 1980, harvesting has been totally mechanised.