Alcohols ability to draw out flavoursome substances from herbs and spices by infusion and then preserve those flavours has been used since the Middle Ages...
I use an excellent Danish site for reference. It is unfortunately only in Danish and probably not updated anymore, but you could use Google Translate and ctrl+F-search (cmd+F on a Mac) using the latin name of the plants you seek as search terms.
http://www.engelund.dk/de-gode-sider_mad-og-drikke/snapseurter/