This "upstream agricultural sector" consists of two activities that follow on from each other chronologically in the Button Mushroom industry sequence: the manufacture of compost, the subsoil on which the mushrooms will grow, and mushroom-growing itself.

The group's composting activity is spread between two centres in Maine and Loire: one near Longué (49), at "La Tourte", and the other in Chacé (49), south of Saumur. The compost produced by the two integrated centres is supplemented by compost from the "La Lande" and "Du Lac" agricultural cooperatives to ensure that the group has all it needs to grow its crops.

The growing activity is carried on at three growing centres where the button mushrooms are grown and harvested; these centres are in "La Tourte", Montoire (41) and Loudun (86). Today, these integrated growing centres provide around 50% of the group's button mushroom requirements, wit the other half coming from cooperative mushroom growers.