Although Rock had no tertiary education, a fact about which he was sensitive and often dissembled, he had a remarkable capability for foreign languages; by the time he reached Hawaii he had a reasonable command of more than half a dozen, including Chinese.

Nevertheless, Rock managed to collect and send back to his sponsors in the U.S. large quantities of plant and bird specimens, as well as many thousands of photographs of geographical, botanical, ethnographic and historical interest.

[3] His style of expeditions typically involved large caravans, which besides the necessary provisions and equipment for storing his specimens and photography, included a personal cook, table with complete dinner setting, a portable bathtub and a phonograph.

[5] When the Arnold Arboretum declined to finance a return expedition, Rock found sponsorship from the National Geographic Society to make a number of trips to southwest Sichuan to explore both the Konkaling range and Minya Konka (Mount Gongga).

These explorations produced a series of articles for the National Geographic magazine, although the editors were hard pressed to reshape them, much to his annoyance, for their more popular readership and to off-set Rock's propensity for accumulative detail over coherent presentation.

The Nakhi Dongba were prolific composers of recitation texts using a unique script typically described as pictographic, although it is better understood as a rebus-like mnemonic device that complexly combines iconic and phonetic elements.

In 1944 the U.S. Army Map Service employed him for his geographic expertise on the Yunnan section of the exceptionally hazardous route designated "The Hump," over which the Allies flew in supplies from India to Chiang Kai-shek's forces in western China.

However, in the aftermath of the defeat of Japan, communist forces soon took control of Lijiang (which had not been reached by the Japanese), making life increasingly difficult for the few foreigners residing there, and Rock left with his collections and manuscripts for the last time in August 1949.

Once he realized that China was closed to him for good, he characteristically spent his last years wandering between Europe, the U.S. and Hawaii, often selling his considerable personal library and collections to support himself and to see his work into print.

He kept detailed diaries and journals throughout much of his life, which frequently express his sense of loneliness—hardly surprising given his choice to live in remote, alien environments; but he clearly prized his independence and individual self-esteem above personal relations.

Emotionally volatile and autocratic in manner, he had a well-deserved reputation as a difficult character, which was counter-balanced by his effectiveness in carrying out extremely challenging and often dangerous projects and the high quality of his work as collector, photographer and scholar.

There is a frequent pattern of declaring he wished to leave China for good, but usually a few weeks back in the West, living in luxury hotels, was enough for him to escape from what he disparagingly referred to as "civilization."

Similarly, there were many times when he decided to invite another Westerner to assist and accompany him on his expeditions (in one instance a young Edgar Snow), but usually they only lasted days before Rock sent them back in exasperation, swearing never to repeat the experiment.

However, Rock developed a real affection and admiration for the Nakhi, who he tended to see as a comparatively unspoiled people, and in the later years of his time in China repeatedly declared his wish to live out his life in Lijiang.

[12] In 1913, botanist Anton Heimerl published Rockia,which is a genus of flowering plants from Hawaii belonging to the family Nyctaginaceae, it was named in Joseph Rock's honour.