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tance, especially if all the foliage-bearing shoots are killed. The direct 
injury appears, however, to be confined principally to that part of the 
stem in the immediate vicinity of the peach. There the tissues of the 
stem are browned and killed by the parasite. The distal portion of the 
stem, the leafy shoot axis, often shows no trace of the fungus, butdries 
up as if girdled. Of hundreds of blighted stems examined in 1887,1 
saw none which were not associated with rotted peaches. Last sum¬ 
mer and this summer I observed the same fact, although the blight was 
less prevalent. The earliest varieties blight most, and trees not in fruit 
never blight at this time of year. In the early spring, however, the 
young and tender shoots must be infected by spores. Many such shoots 
were attacked and killed in 1889.* 
As a rule the fungus produces its conidial tufts much less frequently 
on stems than on fruit. Occasionally I have seen them on branches of 
the previous season’s growth, but generally they are more abundant on 
tissues only recently out of the meristematic condition, e. g. on young 
stems in early spring. 
This twig blight is well known to peach growers in Maryland and 
Delaware, and has been for years, although I have never seen any 
printed statement of the fact. In wet seasons it sometimes does more 
injury than the rot, because when many branches are destroyed the 
tree is not only injured, but the next year’s crop is proportionately re¬ 
duced. Iu some instances I have seen as many as one hundred blighted 
twigs on a single tree, the crown of green foliage being curiously inter¬ 
spersed with dead stems and withered leaves. Certain observant peach 
growers, to whom I mentioned the dependence of blight upon rot, as¬ 
sured me that they knew it already and could and did prevent it by 
promptly removing the rotting fruits. One man of large experience 
has known trees to be much injured by neglect of this precaution. 
This paper, in which I have purposely avoided all questions of histol¬ 
ogy, would not be complete without some reference to means of preven¬ 
tion. The difficulties in the way of preventive treatment are great on 
account of tbe omnivorous nature of the fungus, yeti believe that they 
may be overcome and that a large measure of protection is quite within 
the range of possibilities. 
I have quickly induced the rot in apples, pears, and peaches with 
spores taken from the plum ; in cherries and plums with spores taken 
from the peach 5 in peaches and plums with spores taken from the 
cherry. The fungus infecting all these fruits is apparently one and the 
same. It occurs destructively on peaches, apricots, plums, and cherries, 
to some extent also on apples, pears, and quinces. It has also been re. 
ported as growing on grapes, gourds, the medlar, and Cornus mas. Dr. 
Arthur induced it to grow on blackberries, and Sorauer on green hazel¬ 
nuts. I also found it to grow in green rose hips, but not vigorously, 
* This blight must not be confused with that caused by a small larva which bores 
in the ends of the sterns in early sirring, and sometimes does considerable injury. 
