Oak leave with two acorns intertwined with a Kauri (native New Zealand) plant's seed cone. In the right field, the designer's initials PB (for Paul Beadle).
According to the description on the cover of the mint set:
"The reverse design symbolises the close ties that exist between the British Crown and New Zealand. Drawn by Professor Paul Beadle of Auckland, New Zealand, it features the leaf and acorn of the English Oak (Quercus Robur) and the leaves and seed cone of New Zealand's Kauri (Agathis Australis), with the words ROYAL VISIT and ONE DOLLAR around the periphery."
The Oak, a majestic tree in its own right has long been prominent in many aspects of English history. Because of its hardness and enduring quality, the timber was used extensively in building England's naval and trading sails ships, the same ships that led to and maintained the establishment of the nation of New Zealand under the British Crown (The Treaty of Waitangi 1840).
The Kauri, truly majestic as a mature tree and firmly installed as "King" of the New Zealand forest, was a prominent factor in the discovery, exploration and early history of the nation."