184 TUTIRA 



shall be able to trace the change from an open track into a high single 

 or double hedge. Like other minor phenomena of the station, a com- 

 bination of special conditions has been essential to their creation. For 

 the development of the former there has been particularly required a 

 steep slope in soft soil, a more or less straight ascent and a heavy rain- 

 fall. The single hedge, moreover, belongs to very early times, when 

 the flock was small, when vegetation especially of the trough of 

 the run was practically unaffected by the few sheep carried, when 

 after a fire, fern and tutu again choked the countryside. In those 

 days, stock driven from one part of the run to another had to be 

 jammed into this growth, a passage forced by the aggregate weight 

 of the mob, as into an almost solid substance. There was but little 

 spread in the movement of the driven animals, the narrow spear-head 

 of trampled bracken was flattened as if rolled by machinery ; with 

 repetition the trodden vegetation was destroyed ; later again, in the 

 centre of the wedge, a depression became worn by traffic. By the action 

 of rain-storms and thunder-showers the little depression was gutted 

 into a wide bare rut ; on the sides of this rut manuka seed lodged 

 and germinated. That is the first phase. 



We have now to suppose that for some reason or another the route 

 was abandoned. Perhaps a more convenient alternative track had been 

 discovered, perhaps sheep were being exclusively used for breaking in 

 another part of the run. Whatever the reason may have been, the line 

 falls into disuse ; the manuka which had germinated on the edges of 

 the rut, the only open ground in the vicinity, grows undisturbed 

 into tall plants. 



The next factor we have to consider is fire. A little, an extremely 

 little difference in surroundings will affect flames not running over thick 

 growth ; moisture emanating from a single fleecy cloud, green growth of 

 plants that spring up alongside paths little used, sorrel, clover, cape- 

 weed, will damp down and extinguish them. Checked on either side, 

 fires to a great degree die down in the vicinity of stock-routes ; sections, 

 at any rate, of such paths remain unburnt sections so continuous that 

 sometimes an old drove-track can be picked up by its tall manuka 

 at a distance of miles, a line of hedge marking exactly where years 

 before the wedge of stock had been driven into dense bracken. A 

 particularly well-accentuated example of this single hedge development 

 used to extend ploughshare and axe have done their work from 



