66 



PLANT HABITS AND HABITATS IN THE 



East of town: The Mount Serle road crosses the plain for about a 

 mile and then enters the undulating hill country. It passes to the 

 north of the Mount of Light, and winds between lower hills until it 

 also passes beyond the Copley district. 



South of town: The Beltana road goes in the midst of the Copley 

 Plain for several miles and at length makes its tortuous way through 

 the Flinders to Beltana and southern towns. 



CLIMATE. 

 Rainfall. 



The climate of Copley can be characterized as arid, with cool winters 

 and hot summers. Owing to its position, about midway between the 

 southern extension of the summer rains and the northern limit of 

 those of winter, some precipitation is to be expected in every month of 

 the year; for the same reason, the rainfall of any season is extremely 

 variable. In table 13 are presented rainfall data for a period of 35 

 years, supplied by the Commonwealth Bureau of Meteorology. It will 



Table 13. — Average rainfall at Copley (Leigh's Creek), South Australia, based on 



records for 36 years. 



be seen that the extreme variation in yearly precipitation is from 1.54 

 to 15.64 inches. The seasonal averages are as follows: Summer, 1.95; 

 autumn, 2.4; winter, 2.3; and spring, 1.76 inches. Another feature 

 of the rainfall at Copley does not appear in the table, but was seen in 

 daily reports very kindly put at my disposal by Mr. Bromley, meteor- 

 ologist at Adelaide. This relates to the maximum rainfall for one day. 

 Records covering 6 years, 1901 to 1906, inclusive, were examined. The 

 greatest rain for 24 hours during this period was on December 28, 1903, 

 when 3 inches were reported. This, it will be noted, is about twice 

 as much as occurred during the year of minimal rain as given in the 

 table. 



The rainfall at Copley, however, as has been shown in another place, 

 is not always in amount suflBcient to be of direct use to plants. In fact, 

 it was shown that for the years 1901 to 1906, inclusive, approxinmtely 

 19 per cent of the rain occurred in showers of 0.15 inch or less. The 

 amount of 0.15 inch rainfall was placed as the minimum after the 

 following observations had been made at Copley, supplemented by 

 others at Ooldea. On August 20, after a slow rain amounting to 

 0.21 inch, fairly fine soil containing some sand on the plain was found 

 to have been moistened to a depth of 4 cm., and coarser soil also on 



