AIRA AVENA. 
401 
upon the limestone scars of the western hills and dales, 
ascending to the Main Limestone cliffs that crest the western 
slope of Micklefell, descending to the Yore side at Aysgarth 
force. See remarks under Galium sylvestre. 
Aipa caespitosa L. Native. Area general. Range 
0-650. Common in thickets and grassy places, ascending 
to the limestone pavement of Camfell, and the gritstone 
plateau of Pin Seat. 
A. flexuosa L. Native. Area general. Range 0-700. 
Common upon heaths from the Central Valley upwards to 
the peak of Lovely Seat. 
A. caryophyllea L. Native. Area 87654321. 
Range 0-300. Frequent upon dry banks throughout the 
Lower zone, ascending to the edge of the Hambleton 
plateau near Whitstoncliffe. 
A. praecox L. Native. Area 98754321. Range 
0-600. Frequent upon sandy heaths, especially amongst the 
hills, ascending in Swaledale to Hollow mill cross and the 
plateau of Pin Seat. 
Avena sativa L. Commonly cultivated in the low coun- 
try and up to 350 or almost to 400 yards, and above 200 yards 
much the most frequent cereal crop. The varieties with a 
one-sided panicle are most productive in the low country, but 
the old-fashioned form with a panicle like A. fatua is more 
hardy, and is still often grown upon upland clayey soils. 
A. fatua L. Colonist. Area general. Range 0-300. 
Frequent in cultivated fields, ascending to the Hambleton 
plateau above Hawnby. 
A. ppatensis L. including alpha Smith. Native. Xero- 
philous. Area 98732. Range 0-500. Frequent amongst 
the limestone hills both upon the east and west of the Central 
Valley, ascending in Swaledale to the south end of Keasdon, 
in Teesdale to Cronkley and White Force scars. In the 
Central Valley by the Tees side between Croft and Dalton. 
Bot. Trans. Y.N.U., Vol. 3 
