The basic rules indicate that the area around a covenant can provide some amount of raw vis per year (p 72). Does that raw vis need to be extracted as per the vis extraction rules in the laboratory section (p 94)?
Ars p.72 is about designing vis sources for the covenant (5 build points per pawn per year), which do not need to be extracted using a lab activity. These sources need to be collected, and might be contested or temporary depending on what other aspects you choose in covenant creation. These vis sources are generally considered a repeating source available each year. Vis extraction (Ars p.94) is for extracting additional vis, and is not a repeating source. A covenant vis source can be of any type, as described in the setting. Vis extracted from an aura in a lab is always Vim.