REPORT 0^ THE PRICKLY-PEAR TRAVELLING 



COMMISSION. 



TO THE HONOURABLE THE SECRETARY FOR PUBLIC LANDS. 



Brisbane, 25th November, 1914. 



SiE, — ^We have the honour to submit the subjoined report of oiir 

 investigations. 



We have, &c., 



T. HARVEY JOHNSTON, 

 HENRY TRYON. 



SUMMARY AND RECOMMENDATIONS. 



INTRODUCTORY. 



It may be pointed out that prickly-pears or opuntias, of more than 

 one kind, are pests of agricultural and pastoral lands, locally, in many countries 

 besides Australia — for example, India, Ceylon, and South Africa, as well as in 

 North and South America and the West Indies. The pest pears of most of 

 these regions, however, being especially spiny species, while the common pest 

 pear of Queensland and New South Wales {Opuntia inermis) is comparatively 

 unarmed, do not lend themselves so readily to spontaneous dissemination and 

 propagation as does the latter, since cattle, one of the chief agents in these 

 processes, are debarred from access to them, and as a result the ground does not 

 become littered to any extent with fragments each capable of originating a new 

 plant-individual. For the same reason, the fruits of the former are less likely 

 to be partaken of and their contained seeds carried far afield with their germin- 

 ating powers not only preserved but enhanced. These remarks do not apply, 

 however, to prickly-pears of the class represented by 0. aurantiaca, which are 

 of a very brittle nature, for in their case this spininess of the joints actually 

 brings about their adherence to, and transportation by, animals browsing 

 amongst them. 



ITINERARY. 



The Prickly-pear Travelling Commission entered upon its inquiries on 

 1st November, 1912. In order to become more familiar with the problems 

 to which it had been called upon to address itself, it visited Westwood, Rock- 

 hampton, Gayndah, and Dulacca where infestation was heavy. Thereupon it 

 proceeded to Sydney to obtain advice and assistance from Mr. J. H. Maiden, 

 Government Botanist of New South Wales, who has for many years been actively 

 interested in opuntias. 



Some investigations were made in Java whilst en route to Ceylon. After 

 concluding our work in the latter island, India was visited. In order to cover 

 the field more expeditiously the Commission divided its labours, one member 

 proceeding to Northern and North-western India, while the other confined 



