476 Transactions. — Botany. 



A very perfect example of the second growth may be seen 

 on an old pa (Okuratope) at Waimate North, which is par- 

 ticularly interesting and instructive, as the period can be 

 approximately defined during which it has taken place. The 

 pa is situated on the crest of a clay ridge cropping out 

 through the volcanic country, and is surrounded on three 

 sides by heavy bush, the fourth being bounded by a deep 

 swamp. It was occupied by the great chief Hongi in 1814,* 

 but appears to have been deserted soon after, since when the 

 bush has grown up undisturbed ; and at the present time it is 

 covered by a dense growth only distinguishable from the 

 virgin forest by the smaller size of the trees ; in fact, .were 

 not the attention arrested by the form of the earthworks, 

 which are in almost perfect preservation, the difference might 

 easily pass unnoticed. Within the small area of 2 or 3 

 acres almost all the trees of the adjacent bush have made 

 their appearance, and it is interesting to see the manner in 

 which the different species have taken advantage of the vary- 

 ing local conditions. On the top, where the crest of the hill 

 has been levelled off to form the upper platform of the pa and 

 the hard clay subsoil is exposed, the ground is occupied by a 

 tall thicket of tea-tree intermingled with a few tanekahas and 

 other trees only found in such situations. Surrounding these 

 a line of towais — some of them as much as 3 ft. 9 in. in cir- 

 cumference — cling to the almost perpendicular face of the 

 ramparts. Numbers of the same tree, together with the 

 rimu and totara, appear on the terraces. Fern-trees have 

 sprung up in the vegetable mould accumulated in the ditch, 

 while descending the outer slope, towards richer soil, the 

 species become more numerous, and the new growth shades 

 off almost imperceptibly into the original bush. The whole 

 place supplies one of Nature's object-lessons, in the study of 

 which, however, w^e must bear in mind that forty or fifty years 

 ago there were but few cattle running at lax*ge, and that con- 

 sequently the struggle for life was not neaidy so intense as it 

 is at present ; in fact, w^ere a similar piece of bush now re- 

 moved in a settled district it would stand a much poorer 

 chance of recoverv. 



6. Imported Trees, dc. 



Any speculation on the future of the New Zealand bush 

 would be incomplete without some notice of the introduced 

 trees and shrubs that have gone wild. Of these, the most 

 important are the willows and Australian wattles, the furze 

 and sweet-briar, the common bramble and one of the thorny 



* The pa was visited and described by Mr. Nicholas, who accompanied 

 the Rev. S. Marsden to New Zealand in 1814. 



