Silphium (also known as silphion, laserwort, or laser) is an unidentified plant that was used in classical antiquity as a seasoning, perfume, aphrodisiac, and medicine.[1][2] It also was used as a contraceptive by ancient Greeks and Romans.[3] It was the essential item of trade from the ancient North African city of Cyrene, and was so critical to the Cyrenian economy that most of their coins bore a picture of the plant. The valuable product was the plant's resin (laser, laserpicium, or lasarpicium).
Silphium was an important species in classical antiquity, as evidenced by the Egyptians and Knossos Minoans developing a specific glyph to represent the silphium plant.[4] It was used widely by most ancient Mediterranean cultures; the Romans, who mentioned the plant in poems or songs, considered it "worth its weight in denarii" (silver coins), or even gold.[2] Legend said that it was a gift from the god Apollo.
The exact identity of silphium is unclear. It was claimed to have become extinct in Roman times.[5] It is commonly believed to be a fennel relative in the genus Ferula,[1] perhaps a variety of giant fennel. The extant plants Margotia gummifera,[6] Ferula tingitana,[7] and Ferula drudeana[8] have been suggested as other possibilities. Another theory is that it was simply a high quality variety of asafetida, a common spice in the Roman Empire. The two spices were considered the same by many Romans including the geographer Strabo.[9] In 2021, a study from Istanbul University identified Ferula drudeana as a likely candidate for Silphium, matching both the appearance of Silphium in descriptions and the spice-like gum-resin of Silphium, though without a surviving sample no genetic analysis can be made.[10][8]
The identity of silphium is highly debated. It is generally considered to belong to the genus Ferula, as an extinct or living species. The currently extant plants Margotia gummifera,[6] Ferula tingitana, Ferula narthex, Ferula drudeana, and Thapsia garganica have been suggested as possible identities.[1][8][7][11][12] Theophrastus mentioned silphium as having thick roots covered in black bark, about 48 centimeters long, or one cubit, with a hollow stalk, similar to fennel, and golden leaves, like celery.[2]
The cause of silphium's supposed extinction is not entirely known but numerous factors are suggested. Silphium had a remarkably narrow native range, about 125 by 35 miles (201 by 56 km), in the southern steppe of Cyrenaica (present-day eastern Libya).[13] Overgrazing combined with overharvesting have long been cited as the primary factors that led to its extinction.[5] However, recent research has challenged this notion, arguing instead that desertification in ancient Cyrenaica was the primary driver of silphium's decline.[14]
Another theory is that when Roman provincial governors took over power from Greek colonists, they over-farmed silphium and rendered the soil unable to yield the type that was said to be of such medicinal value. Theophrastus wrote in Enquiry into Plants that the type of Ferula specifically referred to as "silphium" was odd in that it could not be cultivated.[15] He reports inconsistencies in the information he received about this, however.[16] This could suggest the plant is similarly sensitive to soil chemistry as huckleberries which, when grown from seed, are devoid of fruit.[2]