210 



On warm days, after rain, the water vapour that is being 

 drawn from the damp moor soil and plants can be easily 

 seen when the moor edge is projected against the skyline 

 in proximity to the observer. The air, though clear, is seen 

 to flow over the tops of the plants, and presents a somewhat 

 similar appearance to heated air rising from a stove. In the 

 local dialect this appearance is known as " summer geese," 

 or " summer colts." 



SWIDDENS. 



The bare spaces caused by burning the moor are called 

 swiddens, and present special features of plant life differing 

 considerably from those of the undisturbed surrounding 

 vegetation. Special attention was directed to these swiddens 

 during the year, and the results published in the Naturalist 

 for January, 1910, under the title of " The Vegetation of 

 Swiddens in North East Yorkshire." This paper dealt solely 

 with the present appearance of the swiddens, but observa- 

 tions are still required which will elucidate the succession of 

 species upon them. Hence it is proposed to follow the 

 aspects of the burnt spaces from year to year, and as it is 

 necessary to commence with newly burnt swiddens, it will be 

 advisable to note the dates on which they are formed. 



The lower parts of Ewe Crag Slack were burnt in the spring 

 and thousands of grit boulders rendered conspicious on the 

 slopes. 



An extensive fire occurred on the summit of Kempswithen 

 on Easter Sunday (April 11th) and took some hours to 

 extinguish. 



Plant Associations. 



The survey of the moorland plant communities has been 

 continued during the year, and though much interesting 

 material was obtained, nothing of a very remarkable nature 

 has to be recorded. Notes, more or less detailed, were made 

 of the following moors : — 



Stony Ridge Eriophoreta (Cotton Grass Moor) 



Pike Hill Moss do. 



Yarlsev Moss Large Juncetum 



May Moss Erica tetralix Moor, the finest 



hitherto observed in N.E. 

 Yorkshire. 

 The above named moors are on the watershed and are very 

 wet at all times. 



