Aceituna de monte (meaning “forest olive”) of the species Ziziphus sativa is not native to Argentina, but was introduced by migrants along the coasts in the province of Santa Fe when the region was colonized over a century ago. Currently, it has adapted and naturalized and is grown in home gardens, on farms and along roads in the Chaco area. Locals recognize three varieties by the shape of the fruit and levels of acidity in the fruit. They have domesticated this plant, but explain that to reproduce, the seeds must be activated through the digestive tract of chickens or geese. It is a leafy tree some 6-8 m in height with a straight trunk and twisted branches with thorns. Flowering begins in April and lasts for several months until fruiting. The fruit turns from green to brown when ripe. It has white flesh and contains two seeds. The roots have also been used as a food source for the indigenous families in Canadá (in north-central Argentina), though this tradition has been in decline recently. Aceituna de monte is harvested for family consumption, and not sold commercially. Aceituna de monte has an excellent energy level that comes mainly from carbohydrates, and compared to other fruits of the Chaco forest, it also has a good level of protein, fats, minerals and pectin. The fruits are soft and have a fresh flavor and are customarily eaten straight from the tree. They say that when children go to school walking down the hill they can ‘fill their bellies’ with aceituna de monte. Fruits can also be made in to jams or marmalades. The ecosystem of the South American Gran Chaco is threatened with permanent damage due logging of the forests (monte), which has brought a decline in local food availability. The indigenous hunting and gathering people of the area used to have access to abundant wild flora and fauna. Acietuna de monte, adapted to this ecosystem, is at risk due to the continuing decline of the habitat and the loss of cultural patterns that support nutrition in this region.