82 



CARL SKOTTSBERG, A BOTANICAL SURVEY OF THE FALKLAND ISLANDS. 



Besides, I have used the records on rainfall, as published in the annual Colo- 

 nial Reports. 



II. Port Stanley, Government House, Rainfall 1905 — 11, Observer: A. Linney, 

 Gardener {22). 



M 11 1 h 



c 



1-5 





ja 



O. 



1^ 



a 



3 

 I-s 



1-5 



3 

 < 





o 

 O 



o 



6 



bo 

 c 

 'C 



a< 



CO 



1h 



& 



3 



02 



a 

 B 



o 



3 

 <1 



Winter 



a 



Amount in mm. . . 



79.0 



60.0 



48.1 



61.8 



71.6 



53.4 



60.0 



52.5 



25.3 



41.3 



52.1 



68.9 



118.7 



207.9 



181.5 



165.9 674.0' 



Nnmber of claj's . . 



16.4 



16.9 



15.9 



19.9 



23.0 



21.7 



22.4 



20.4 



14.4 



17.1 



16.0 



19.7 



47.5 



53.0 



58.8 



64.5 223.8 



The rainfall was not so great as during the period in Tab. I ; total average of 

 all observations 705 mm. in 232,8 days. 



Let US now try to establish the relations between the climatic factors and the 

 character of the vegetation. The climate is of a very distinct insular type. The 

 summer is not very warm, and there is hardly a month when a slight frost cannot 

 be expected. Further, there is not a very marked periodicity, for the winter is 

 mild, and it is qnite natural, that annual species should be scarce, that open or 

 little protected buds should be a common feature, and that evergreen species should 

 be frequently met with; however, periodicity is sufficiently marked to produce a 

 constant rest in floral phenomena (see below). The vegetation enjoys but little sun- 

 shine, and there is not such a great difference between sunny and shaded slopes as 

 in many other countries. 



It is to be regretted, that no observations have been made on the temperature 

 of the soil, save for what I have published {14, p. 8). However, we may easily 

 imagine, that the Falklands have a cold, moist soil throughout the year, but also 

 that it is seldom härd frozen and never to any considerable depth. In spite of the 

 regular amount of rainfall, the plants can be expected to show a marked xerophytic 

 structure, especially as the formation of peat is exceedingly favoured by a chmate 

 such as this. Another factor has the same influence, viz. the strong wind. The 

 Falkland Islands are very windy indeed, and I have already shown, that the ever- 

 lasting westerly winds account for the total absence of arboreous vegetation {14, 

 p. 6). This is easily proved by the experiments made by the inhabitants. Especially 

 instructive is the small planted * forest» in Hill Co ve on West Falklands. There is a 

 small depression, where a number of Éuropean trees, principally Scotcli firs, seem 

 to thrive well. But they only attain a very limited height, for as soon as their 

 shoots rise above the shelter they are killed. Everybody in the Islands knows very 

 well that it is impossiblc to grow trees without protecting them to the W. And 

 table I indicates that winds between NNW and SSW predominate. Fig. 10 shows 

 a hawthorn tree in Stanley, planted behind a wall; the wind cuts it off level with 

 the shelter and has given its head a characteristic, one-sided shape. 



^ Maximum 936,3, minimum 526,9 mm. 



