This study assessed the variation in herbage protein and fiber content as well as concentration of furocoumarins, plicatin B, (E)-werneria chromene, and pterocarpans of pitch trefoil (Bituminaria bituminosa) germplasm sampled in situ in both summer and autumn in Elba Island, Italy. Populations were sampled from a range of climatic and edaphic conditions, on light soils with pH > 7.5. Valuable variation occurred for forage quality and chemical composition. The quality features, relevant for a possible forage utilization of the species, were promising for the leaves, which represented about two-thirds of the total aerial biomass in early summer and the whole green regrowth in autumn. The species can also represent a source of psoralen, angelicin, plicatin B, bitucarpin A, and erybraedin C for possible pharmaceutical and/or agrochemical use, with individual populations showing high levels of these compounds.
Keywords: angelicin; forage quality; furocoumarins; psoralen; pterocarpans.