Here's the stick insect Ned illustrated in 'In the Garden', on page 15, hiding in the manuka.
Another place to find information about stick insects written for a general audience is Te Ara: The Encyclopaedia of New Zealand.
There is scientific information about stick insects as well as lots of photos on the Landcare Research website. One thing I learned from this site is most stick insects are female, with some populations having only females, who reproduce without the help of males, called parthenogenesis.