Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
* sarpo, no perf., sarptum, 3, v. a. [root sarp-; Gr. ἁρπάζω]; in agricult. lang., to cut off, trim, prune, clean: sarpta vinea putata, id est pura facta: unde et virgulae abscisae sarmenta. Sarpere enim antiqui pro purgare ponebant, Fest. p. 322 Müll.