308 
freezing in winter, but has no proof, except analogy with roses, which leave 
out in spring but die in June and July suddenly, and havea black dead 
pith. But in roses it is last year’s shoots that die, while in pears it is limbs, 
four, five or more years old, which are stricken, followed by the younger 
portions. Thinks that microscopic examination might show the cells weak- 
-ened by frost or other injury, and the presence of fungi, whose spores are 
always ready to develop in proper nidus. But the frost theory is weakened 
by the fact that trees on high well-drained soil often blight worse than in 
‘low damp situations. Trees otherwise perfectly healthy blight badly 
1867. MEEHAN, T. (Germantown, Pa.), and others. Dis- 
eases of the pear [with discussion.] Proc. Am. Pom. 
Soc. for 1867, p. 57. [6 pages on blight. | 
Same (without discussion) in Trans. Ill. Hort. Soe. 
for 1867 (in Ill. Dep. Agric., vol. vit), p, 502.% [2 
pages. | _ 
The insect blight is due to the Scolytus pyri. Frozen sap blight is due to 
‘the inability of the plant to maintain, at any certain spot, ‘heat enough to 
maintain life,” which occurs whenever the evaporation exceeds the supply 
of moisture. This takes place when the ground is frozen. Fire blight 
proper is far the most injurious. ‘‘Here, I am satisfied, we have to 
deal with a parasiticfungus.” It growsin the bark, ‘‘causing fermentation,” 
and when it girdles the limb, the sap is prevented from rising and the part 
above dies ‘‘as if cut away or thrown into the fire.” He aims a blow at the 
fallacy that ‘‘fungi only attack diseased vegetation.” Remedy is to cut and 
burn the diseased parts in order to stop the spread of the fungus spores. 
Dr. H. Claggett (St. Louis, Mo.) saved trees by shaving off the diseased 
bark. He thinks it due in dwarfs to ‘‘want of affinity between the pear and 
the quince.” A neighbor of his ‘‘believes he has found a night moth which 
-does this work.” PP. Barry (Rochester, N. Y.) said: ‘‘I confess I have 
nothing to say except what is pure speculation; and I have got tired of specu- 
lation, and of hearing it on this subject.” Excision the true remedy. “1 
do not believe it to be caused by an insect.” G. Husman (Herman, Mo.) 
‘had abandoned high manuring, and cultivation late in the season. EB. 8. Hull 
(Alton, Ill.) also believed it due to a fungus. ‘‘I have inoculated trees with 
it.” Recommends and explains root pruning asa preventive. F. R. Elliott 
(Ohio) has faith in copperas water, as recommended by Dr. Kirtland. 
1867. WaARDER, JOHN A. American Pomology, 1867, p, 
174. [9 pages on blight. ] 
Frozen-sap, fungous and insect theories alike unproven. No proof that 
poisons are produced in the limbs. Treatment necessarily unsatisfactory. 
‘Checking annual growth can be done by root pruning in spring. Speaks of 
a “blight” of apples and quinces confined to the twigs; cause obscure, but 
may be due to atmospheric influences. The true apple blight much re- 
sembles fire blight. Quotes from Dr. Kirtland’s address to the Ohio Pomo- 
logical Society to the effect that early in this century it: was a popular 
“opinion that blight and some other diseases of plants, together with spotted 
fever and similar epidemic diseases of the human family, ‘arose from one 
cause,” a view not, however, concurred in by medical and scientific men of 
that day. Insects, frozen sap, electricity, excessive evaporation, and ex- 
haustion of soil, alike unsatisfactory. Suggests that it is due to the ‘poison- 
“ous impression of the seeds (sporules) of a microscopic fungus,” and suggests 
copperas as a remedy. This is to be applied by washing the bodies of the 
trees with a saturated solution either before or after the blight begins to 
‘show. Might be put on witha syringe. Placing scales of iron about the 
‘tree thought to be good. Salisbury’s views referred to as confirming this 
fungous theory. 

