140 OBSERVATIONS ON THE CALIFORNIA VINE DISEASE 
affected.  Chauzit remarks that he has seen “ vineyards in which 
one quarter of the vines were destroyed,"? and Professor Е. T. 
Bioletti tells me that it has been known to destroy three quarters 
of a vineyard. The symptoms of Folletage vary somewhat 
with the rapidity of the attack; if the vines are affected and 
killed within the space of a day, the leaves fade, curl, and dry; 
but when the attack is less severe the seared leaves will be con- 
fined more to the apex of the shoots, the lower leaves being 
“much discolored, either with red or yellow spots or stripes.” 
The shoots always die from the apex downward and the fruit 
withers and dries up more or less according to the degree of its 
maturity and the seriousness of the affection on the shoots upon 
which it is borne. 
The anatomy of Folletage does not appear to differ greatly 
from that of Brunissure. 
Folletage generally occurs only at midsummer, but may affect 
vines as early as May. 
The accredited cause of the malady is a rupture of equilibrium 
between absorption and transpiration. 
Rougeot* is a mild form of Folletage and Pierce says the 
following description would apply to leaves of vines affected by 
this malady: 
“Тһе leaves of the dark varieties of grapes show a red dis- 
coloration between the veins and at the margin. In the earlier 
stages this color is faint, but later on the tissue lying between 
the main veins becomes bright red, and still later dies and changes 
to dull brown. Тһе death of the leaf usually begins at the mar- 
gin, or in the center of the red stripes lying between the veins, 
or it may involve both regions at once. The venation of the leaf 
remains green in most instances, forming a symmetrical green 
vem system after nearly all the intervening tissue is dead, of 
has turned red or brown. Thus there are in these later stages 
three distinct gradations of color in the affected leaves: (! 
A brown and more or less dried margin, or bands of brown lying 
between the main veins, or both; (2) a band of bright red bor- 
dering the dead brown portion of the leaf; ( 3) normal gu 
: Foéx, с. Cours complet de viticulture, 573. [ed. 4]. 
кыруы В. Revue de Viticulture 26: 50. 1006. 
Pierce, N. B. Loc. cit., 106; 
is Rougeot of authors pro parte. 
HR 
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