Hemideina trewicki, the Hawkes Bay tree wētā, is a large arboreal long-horned cricket in the order Orthoptera.

Hemideina trewicki is common in forests and suburban gardens over most of the Hawke's Bay region.

[4] The two species can be found sharing daytime refuge holes but hybridisation is limited to rare first generation hybrids.

[5] Tree weta are hemimetabolous insects, meaning they hatch from eggs as small versions of adults.

Over about 12 months nymphs grow and molt nine times before reaching full size (8–12 grams) and sexual maturity.