420 
Journal of Agricultural Research 
Vol. II, No. 6 
No attempt was made to deterniine whether any of the spores other 
than those of the chestnut-blight fungus belonged to parasitic species. 
Judging, however, fiom the large numbers and kinds of fungous spores 
carried and from the very high numbers of spores of Endothia parasitica 
obtained at certain times, it is reasonable to suspect that these birds 
or birds of other species may be important agents in the spread of some 
other plant diseases, at least under certain favorable conditions. In 
the light of facts revealed by this investigation it is suggested that 
birds may play a part in the dissemination of such troubles as the brown- 
rot of stone fruits, die-back of peaches, plums, and apricots, or of any 
other diseases where birds may be attracted to the host. 
SUMMARY AND CONCLUSIONS 
(1) The 36 birds tested belonged to 9 different species. 
(2) Of the 36 birds 32 were those which are in the habit of climbing 
over the trunk and larger branches of trees. 
(3) Most of the birds were shot from blighted chestnut trees; some 
directly from blight cankers. 
(4) The bill, head, feet, tail, and wings of each bird were scrubbed 
with a brush and poured plates were made from the wash water, which 
was retained and centrifuged for its sediment. 
(5) Of the 36 birds tested, 19 were found to be carrying spores of the 
chestnut-blight fungus, Endothia parasitica . 
(6) The viable spores of the chestnut-blight fungus carried by two 
downy woodpeckers numbered 757,074 and 624,341, respectively, while 
a brown creeper carried 254,019. 
(7) The cultures from some of the birds showed from 2 to 14 times as 
many viable spores of the chestnut-blight fungus as of all other fungi 
combined. 
(8) The highest positive results were invariably obtained from birds 
shot from two to four days after a period of considerable rainfall. 
(9) The rate of development in cultures always indicated that the col¬ 
onies of the chestnut-blight fungus originated from pycnospores; pycno- 
spores were generally found in the centrifuged sediments, while asco- 
spores were never detected. The birds were therefore carrying pycno¬ 
spores only. 
(10) The pycnospores carried were probably brushed off from either 
normal or diseased bark, or from both, in the movements of the birds 
over these surfaces. 
(11) Both the cultures and an examination of the centrifuged sedi¬ 
ments showed that the birds were carrying a large number of spores of 
many species of fungi other than Endothia parasitica. 
(12) From the above facts the writers are led to the conclusion that 
birds in general are important carriers of fungous spores, some of which 
may belong to parasitic species. 
