312 
Journal of Agricultural Research 
Vol. I, No. 4 
with the margin darker. Perithecia epiphyllous, minute, lenticular, black-brown, 
100 fi broad. Sporules oblong or ellipsoid-oblong, 5 — 8X2 — 2.5/i. The fungus is also 
found on old insect-galls on the same leaves. The 40th Rep. was given to the public 
in May, 1888. P. Caryae E. & E. was not published till October, 1888. P. Caryae Pk. 
and P. Caryae E. & E. are evidently the same 1 
The leaf spots upon the pecan assume the reddish brown color at a 
very early stage of development, though this is often preceded by a 
slight yellowing of the tissue at the point of infection. Furthermore, 
the grayish center is almost invariable in its appearance during the 
later stages. Individual spots have rarely been found by the writer to 
exceed 4 or 5 mm. in diameter, but by the coalescing of several initial 
infections diseased areas at least up to 8 or 10 mm. have frequently 
been observed. 
The majority of the pycnidia have been found to vary but little from 
100// in diameter, but extremes of 50 to 150 n have been noted for mature 
pycnidia in culture. In the latter case they are usually much lighter in 
color than on the host, assuming macroscopically a tawny appearance. 
On the pecan leaf and occasionally in culture the fruiting bodies are 
dark brown to black. 
Conidia as observed on this host have corresponded closely with 
Peck’s fungus, ranging within the limits of 3.8 to 6 by 1.5 to 2 /*. In other 
points also the pecan fungus corresponds closely with the two descrip¬ 
tions quoted above. 
Thus, on account of the close relationship between the hosts and the 
many points of resemblance between the fungi and the disease symp¬ 
toms, it seems best to consider the nursery-blight fungus as identical 
with Phyllosticta caryae Peck rather than to burden mycological litera¬ 
ture with another name. At least this course should be followed until 
cultural and cross-inoculation work can demonstrate a specific difference. 
BROWN LEAF-SPOT 
[Caused by Cercosporafusca, emend, sp.] 
history and distribution 
With the growth of the pecan industry the brown leaf spot has grad¬ 
ually been receiving more notice among orchardists. Since it is by no 
means as serious a trouble as the pecan scab, it has not merited the 
attention given the latter. No published record has been found, except 
a brief description of the fungus, and no work establishing the cause or 
demonstrating a method of control. 2 However, next to the pecan scab 
it is perhaps the worst and most generally distributed leaf-spot disease 
1 Ellis, J. B., and Everhart, B. M. The North American Phyllostictas. Vineland, N. J., 1900. p. 35. 
2 The brown leaf spot has occurred to a limited extent at points where spraying tests were being carried 
out on other pecan diseases and has been effectively controlled with three treatments of Bordeaux 
mixture. 
