The Harvester symbol.
Harvester weapons were deadly nanobiogenic devices used during the wars between the T'Lani and the Kellerun. Each harvester consisted of two cylinders of lethal orange gel. In 2370, both sides applied for Federation assistance to destroy the harvester devices. Julian Bashir and Miles O'Brien were assigned to help neutralise the weapons, using muon frequencies. (DS9: "Armageddon Game")