posted 4 days ago
I'll second what Douglas said. A section is a group of closer-related species within a genus, usually named after the most common, well-known or otherwise most prominent species. So section Myrtillus is a group of species closely related to Vaccinium myrtillus. Sometimes this coincides with a shared common name (many of the species in section Myrtillus are called bilberries), and sometimes it does not. Also, to add to the confusion, it's not always clear where the boundaries between different sections should be, and there often seems to be differing opinions among botanists. Hope this helps.
Oh, and welcome to Permies!