Effects of a Bush Fire on the Vegetation of Signal Hill. 
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Juncus bufonius. 
Small grass. Not in flower ; possibly 
Agrostis lachnantha. 
This year a visit was paid in November. The only record of note was 
the abundance of Ornithogalum pilosum, a plant which until recently had 
been considered rare on the Peninsula. 
In March 1921, a little over two years after the fire, a few plants of 
Antholyza lucidor were in flower at the top of the patch, but as the particular 
region in which the plants were found had not been visited in any previous 
March, there were no records of the behaviour of this species. Senecio 
pubigerus, which in 1920 had been confined to the shelter of the bushes, 
had spread widely over the slope of valley A and elsewhere was quite a 
common plant apart from the larger bushes. One young silver tree 
(Leucadendron argenteum) was seen near the top of the patch. 
During the late winter and spring months rapid growth took place over 
the whole area, and on the northern slopes of the valleys a number of 
seedlings of Erica viridi- purpurea were noted coming into flower for the 
first time. On the slopes between valleys B and C a single plant of Protea 
grandiflora was noted. The shoots of this had obviously come up from the 
underground stock. On the ridge between valleys A and B a group of young 
plants of Relhania ericoides and several young plants of Selago ramosissima 
were seen. 
The spring flowers of this year showed a still further reduction in number 
and quality, with the exception of Babiana stricta. This species was 
exceptional in that no obvious effects of the fire manifested themselves in 
this or in previous years. This may be due to the fact that the corms are 
unusually deeply seated. 
General Conclusions. 
It is clear that in certain plants rapid growth was induced after the fire, 
while in others the vegetative parts were wholly killed and the plants had 
to rely upon their seeds for the continuance of life. 
The exact way in which fire influences the plant is not clear. Several 
factors may be at work. Possibly the heat during the fire acts directly on 
the underground organs, mobilising all the forces of the plant. It is a well- 
known fact that by employing high temperatures the normal time of flower- 
ing in certain plants may be anticipated (4). In the case of those plants, 
notably Asparagus capensis, in which the flowering period was obviously 
induced at a somewhat earlier time than usual, it is probable that the heat 
acted directly on the underground organs. It is also likely that the direct 
action of heat was responsible for the production of the large number of 
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