Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
pŏpŭlātus, ūs, m. [populor], a laying waste, a devastating, devastation (poet.), Luc. 2, 634: squalent populatibus agri, Claud. in Eutr. 1, 244: coërcere populatibus, Sid. Ep. 3, 3, p. 181, 40.