Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
hărundĭnātĭo (ar-), ōnis, f. [id. II. L.], the poling of vines, the propping with reeds, Varr. 1, 8, 3 (ex conj. Schneid. The vulg. reading is: Canusini in harundulatione in ficis).