Cistus ladanifer was collected from two sites, in July-August 2001, after the flowering season. The major quantity was brought from the wild, where the plant was growing in the mountainous region of the center-interior of the country (site 1). A smaller amount was harvested from a cultivated plant in the north of Portugal (site 2) that was propagated from a wild plant found in the dry plain region in the South of Portugal.

Considering the oil composition of cistus plants from different sites, there were found some differences. The cistus oil of site 2 had a high content on the ocimenone isomers, an absence of trans-pinocarveol and unknown (compound 17) and a higher quantity of less volatile compounds such as sclareol oxide and 15-nor-labdan-8-ol. Cistus oil from site 1 was richer in sesquiterpene alcohols and 2,2,6-trimethylcyclohexanone. The amount of ambrox was the same for both oils. Considering the use of fresh or dry plant, the composition of cistus from site 2 was more affected, decreasing the amount of components of middle to high volatility and increasing the amount of the less volatiles. Drying promoted the doubling of the amount of ocimenone isomers in cistus oil from site 2 and of unknown (compound 21) and sesquiperpene alcohol (compound 29) in cistus from site 1. Again the quantity of ambrox was the same for both oils.