Berry
The term berry refers botanically to the edible, fleshy ovary of a flower. However, colloquially, people use the term to refer to small, pulpy fruits, most often growing in bushes.
Most of the berries we'd think of today - strawberries, raspberries, blueberries, blackberries, etc. - grew in temperate zones and thus can no longer grow in the Fifth World's hotter climate. However, many species of tropical berries still grow, such as lychees, kumquats, sea grapes, jabuticabas, and a wide variety of fruits referred to as one or another type of "cherry." (e.g., Barbados cherry, Jamaican cherry, Suriname cherry, etc.) These fruits bear no relation to the now-extinct cherry except vague resemblance in color, shape, and size. In places where only one such species can get a foothold, the locals will often refer to the fruit of that plant by a name ultimately descending from the word "cherry."
#Human usage
Humans ate berries long before the invention of agriculture, and continued to do so after collapse. People of the Fifth World eat berries raw, mashed into compotes, or made into jams or other desserts. They make jam as the ancient Romans did - fruit mashed and preserved with honey, then stored in ceramic jars. People also use some berries to make dyes for clothing, sleeping-mats, or artwork.
#Specialization
A community specializing in relationship with berries may make and trade jam - and that would require a close relationship with the local bees (for honey) and a source of clay (for ceramics). Such a community might have many trading relationships with other communities. They might value potters and apiarists highly.
Such a community might have different camps for each step of the process: a berry-gathering camp, a potters' camp, a honey-harvesting camp - especially if their source of clay lies far away from where the berry trees or bushes grow. These camps might have different rules and norms from other camps. They might have traditions about only making jam at particular times of year, or only in a particular way.