Robert Connell Clarke

In 1977, shortly after graduating, Clarke self-published his undergraduate research dissertation[7] under the title "The botany and ecology of Cannabis."[11] He would spend the following years continuing to research and publish on the topics of evolutionary and botanical history of the plant genus.

Some of Clarke's key publications include:

• Marijuana Botany. An Advanced Study: The Propagation and Breeding of Distinctive Cannabis (And/Or Press, 1981)[12] ISBN 978-0914171782
• Hashish! (Red Eye Press, 1998)[13] ISBN 9780929349053, 0929349059
• Hemp Diseases and Pests: Management and Biological Control – an Advanced Treatise (CABI Pub, 2000), with John M. McPartland and David P. Watson. ISBN 978-0-85199-454-3, 978-1-84593-313-5
• Cannabis: Evolution and Ethnobotany (University of California Press, 2013),[14] with Mark D. Merlin. ISBN 978-0-520-29248-2

Some of his publications received an important echo. According to Clarke, "Marijuana Botany played an unforeseen role in spreading plant science to the public."[7] Clarke also published numerous peer-review articles that received less public attention.[15]

Clarke is known for having studied a number of local varieties, cultures, and agricultural practices linked to cannabis in remote regions of the world in Southeast Asia, such as Nepal, China, Vietnam, but also in other areas of Africa,[16] Europe, the Americas,[5] and Oceania.[17] In 2018, a promotional documentary was released by a Canadian hemp company documented Robert Clarke's journey through Turkey exploring local traditional hemp cultures.[18]

In relation to this field work, Clarke has participated in the development of methodological tools for cannabis research.[19] He has also been associated with the discovery and identification of archaeological remains of cannabis in the Israeli Tel Arad site.[20][21]