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CHAPTER XXIX. 



FIRE AND FLOOD WEEDS. 



PREVIOUS to the 'eighties the effects of burning out the indigenous 

 vegetation of the run had been almost imperceptible ; ground tempo- 

 rarily cleared had immediately lapsed into its former condition. As, 

 however, the flocks and herds of the station increased, the ground 

 consolidated and the bracken growth diminished ; above all, as light 

 penetrated to the surface, certain weeds one after another temporarily 

 took possession of the fire-blackened tracts. On the better soils of 

 eastern Tutira appeared such plants as Melilotus arvensis, Medicago 

 lupulina, Medicago denticulata, and Sonchus oleraceous ; on lands good 

 and bad, Carduus lanceolatus and Briza minor ; on grass lands over 

 which in dry summers fires had run, Bromus mollis ; on pumiceous lands, 

 Hypocheeris radicata, Silene gallica, Cerastium glomeratum, Trifolium 

 dubium, and, at a later date, Erigeron Canadensis. 



Taking these aliens in the order named, field melilot (Melilotus 

 arvensis) has never spread beyond the alluvial lands around Tutira 

 lake. Only after flax-fires great or small did the plant show itself ; then 

 on rich grounds left black and bare, it appeared, tall, rank, and luxuriant, 

 for a single season. Toothed medick (Medicago denticulata) and 

 nonsuch (M. lupulina}, other fire weeds, throve only on fertile hills 

 and flats ; they never even germinated on the pumice lands of the 

 trough of the run, though their seed was prominent in the numerous 

 sacks of tailings scattered broadcast over that area. Neither of these 

 members of the pea-flower family took possession on a great scale : I 

 have never seen Melilotus arvensis spread over more than thirty acres 

 as a dense crop, whilst the others never overran more than a few square 

 yards outside of the garden ; they were only to be found prominently 

 on land over which fire had passed. 



