FIRE BLIGHT 
361 
spread the blight among the flowers. Inci¬ 
dentally it may be remarked that not all 
blighted pear blossoms are the result of 
fire blight. In the Hudson Valley, accord¬ 
ing to Dr. E. Porter Felt,' the injury is 
caused by pear thrips. These little insects* 
which are about 1-20 of an inch long, ap¬ 
pear on the trees as the buds start and seek 
shelter in the expanding flower buds, blast¬ 
ing the bloom, which presents a brown 
seared appearance. 
SUMMARY OF ABOVE OBSERVATIONS. 
A brief summary of the above state¬ 
ments is as follows: 
1. Fire blight appears both before and 
after pear and apple trees bloom, and in 
nursery plantations which have never 
bloomed. With such outbreaks the honey¬ 
bee has no connection. 2. It has been 
shown experimentally that fire blight is 
spread by hosts of sucking and biting in¬ 
sects, such as plant lice, leaf hoppers, the 
tarnished plant bug, and probably many 
flies and beetles which puncture or feed 
on leaves and flowers. 3. Since honeybees 
restrict their visits to flowers they do not 
carry blight from the foliage to the bloom. 
This is done in many instances by plant 
lice, which creep in and infest the buds 
before they expand; and also doubtless by 
many flies and beetles which fly freely back 
and forth between the leaves and the 
bloom. Honeybees will not visit blighted 
inconspicuous bloom, but flies will often do 
so. While honeybees may occasionally car¬ 
ry the germs, they are of so little impor¬ 
tance compared with other distributors that 
their absence from orchards would proba¬ 
bly not affect the prevalence of blight. 
PEAR BLIGHT WIND BORNE. 
At this point the defense of the honeybee 
against the accusation of carrying fire 
blight rested up to Nov. 1, 1918. On this 
date there appeared in Science a paper by 
F. L. Stevens, W. A. Ruth, and C. S. 
Spooner of the University of Illinois, en¬ 
titled “Pear Blight Wind Borne,” which 
advanced new and revolutionary evidence 
in favor of bees. A brief abstract of this 
paper, given largely in the words of the 
authors, is as follows: Twelve-mesh wire- 
screen cylinders, 15 cm. in diameter and 
30 cm. long were constructed to enclose 
parts of single branches. Some of the cyl- • 
inders were slipped into closely fitting 
sleeves of fine bolting cloth. The ends of 
both kinds of cylinders were covered with 
canvas extending past the wire far enough 
to permit secure tying. The exposed wire 
of the first type of cylinder was painted 
with a mixture of tanglefoot and benzine. 
No insects were found in any of the cyl¬ 
inders except one which was accidentally 
permitted to dry, and in which two insects 
were found, but the shoot did not blight. 
The purpose of the following experiments 
was to discover whether infection was as 
common in the cylinders as in the open. 
Ten cylinders enclosed flowering wood. 
Flowers in two of the cages blighted. 
Forty cylinders, 20 of the bolting cloth and 
20 of the tanglefoot type, enclosed termi¬ 
nal growth. Thirty per cent blighted, which 
was practically the same proportion as 
prevailed among the unenclosed terminal 
shoots, as was shown by a count of a 
thousand terminal shoots on these and ad¬ 
jacent trees of the same variety and age. 
Since insects did not obtain access to the 
shoots the blight bacteria must have been 
carried by the wind; and “insects were not 
even of primary importance as carriers.” 
This conclusion was further supported by 
two facts: (1) there was a lack of insects 
in the orchard in sufficient numbers to ac¬ 
count for the large amount of twig blight 
—aphids and leaf hoppers were entirely 
absent during the period of infection; (2) 
insects were entirely absent from the exud¬ 
ing cankers, where they might receive their 
initial contamination. During three years 
of close observation during blooming time 
not a single insect was seen to visit the 
cankers. 
FIREWEED. —See Willow-herb. 
FIXED FRAMES. —See Frames, Self¬ 
spacing. 
FLIGHT OF BEES.— The distance bees 
go in quest of stores varies very greatly 
according to conditions. Usually on level 
country, more or less wooded, they do not 
go over one and one-half miles. If, how¬ 
ever, there is a dearth of pasturage within 
that distance, and plenty of it along some 
river bank three to five miles away, they 
may or may not go that far. When bees 
