Scatter-hoarders usually establish their caches containing one or several seeds across a wide area within their home range. Olfaction plays an important role in cache recovery by scatter-hoarding rodents. The depth and size of caches, and water content of cache substrates are believed to affect seed odor emission and thus olfactory cues to food hoarding animals. We conducted enclosure experiments to study the effects of cache depth, cache size and soil moisture on cache discovery of Pinus koraiensis seeds by Tamias sibiricus in Dongfanghong Forest Dailing District of Heilongjiang Province during August - October, 2012. We found that: (1) The proportions of seed cache discoveries were reduced with the increase of burial depth; seeds buried at 1cm and 2cm deep were more likely to be discovered by T. sibiricus than were those at 4cm and 6 cm. (2) Seed cache recovery rates were also significantly affected by cache sizes; large-sized caches were more likely to be discovered by T. sibiricus than were small ones. (3) High substrate water content facilitated small rodents discovery of the artificial caches. Our results suggest that T. sibiricus rely on olfaction to discover buried seeds under the artificial enclosures and olfaction might play an important role in finding their natural caches. Future work should consider seed odor emission under different substrate conditions.