112 OBSERVATIONS ON THE CALIFORNIA VINE DISEASE 
out soon becoming blighted ; that the disease might affect the vine 
at any time from early spring until the autumn; that it was 
reputed to be, in some cases, very rapid in its action, affecting an 
apparently healthy vine in the space of a day. Morse himself 
had observed no such rapid changes, the changes noticed being 
only “such as one may frequently note in any vineyard where 
sudden variations in meteorological conditions occur, and sun- 
burn or scald follows” ;* predominantly, however, the progression 
of the disease was gradual. 
The malady was characterized, to continue our quotations, by а 
“drying up, and apparent burning of the foliage at all times, 
up to the time of ripening of the fruit. ...2 Тһе leaves in 
general have the very decided appearance of sunburn. When the 
vineyard is seen as a whole the foliage looks withered, leaves 
partially dried and wrinkled, and large parts of them have be- 
come red, the affected part of each leaf assuming no regular 
shape or particular position. The canes having the most upright 
growth and those most exposed have the leaves the worst 
affected; low growth is less troubled.’ 
“ Among the several varieties the Mission is, undoubtedly, the 
worst affected. . .. Other varieties such as Golden Chasselas, 
Sultana, Semillon and Sauvignon are affected to a greater от less 
extent, and in about the order named."* 
Morse believed that the mortality of the vines was "due 10 
more or less accidental and local peculiarities of climate, soil, 
moisture conditions, ес.’ 
In a report? submitted to the State Board of Viticultural Com- 
missioners in 1890, Dowlen described the California vine disease 
with care, and added some remarks on the anatomy of the cane 
of affected vines which I shall have occasion to quote later. This 
' Morse, F. W. Report of an examination into the phenomena and СМ: 
of a supposed vine disease in Los Angeles County. Report of the viticultural 
work during the seasons 1885 and 1886, College of Agriculture, University of 
California, 176, 177. 1886 
Loe. cit., 176. 
Loc. cit; 183, 184. 
в : # +; i ў 
‘Report California Viticultural Commissioners for 1889-90, 57 €t SÉ: | 
