Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
* grandiscāpĭus, a, um, adj. [grandis-scapus], having a large stem or trunk: arbores, ut ita dicam, grandiscapiae (shortly before: magnarum arborum truncos cum scapo suo transferri), Sen. Ep. 86, 19.