Isatis tinctoria
After a period of small subsistence agriculture, the local economy began to concentrate on a few chief exports: initially, lichen (Roccella tinctoria) and woad (Isatis tinctoria), later the introduction of wheat and corn crops. Woad was one of the most important exports from São Jorge and the Azores; it was initially introduced by Willem van der Hagen around 1490, and exported primarily to his countrymen in Flanders. Both woad and lichen were very popular in central Europe as a dye.