In Roman mythology, Sterquilinus ("manure"; also Stercutus or Sterculius) was a god of fertilization. He may have been equivalent to Picumnus. The Larousse Encyclopaedia of Mythology gives the name as Stercutius, a pseudonym of Saturn, under which the latter used to supervise the manuring of the fields.
Early Romans were an agrarian civilization and, functionally, most of their original pantheon of gods (not the later ones they adapted to Greek stereotypes) were of a rural nature with figures such as Pomona, Ceres, Flora, Dea Dia; so it was only apt for them to have a god supervising the basics of organic fertilization.