-3- 
oe 
30 foot-candles will practically stop adult activity, as will complete 
_ darkness. The meter in use will measure from about 0.2 to 500 foot—can- 
_ dles. Activity appears to be greatest when the light intensity is less 
’ than 0.5 foot candle, the intensity which generally occurs a half hour 
_ before sunrise or after sunset. Light reaching the meter from the east, 
west, and overhead was measured. After sunrise or before sunset on a 
_ clear day light intensity may increase or decrease several hundred foot 
' Gandles per hour. Of 304 moths captured on the four days 277 were taken 
_ between 7 and 9:30 p.m., 1 during the day, and 26 between 4 and 5:30 
a.m. Temperatures below 60°F. prevented activity on two of the mornings. 
About 217 of the moths entered the traps a few minutes before or after 
the 8 p.m. examinations." 
» 

large-scale bait-trap experiments for the control of the oriental fruit 
moth (Grapholitha molesta Busck) have been continued, W. P. Yetter, of 
the Cornelia, G+., field laboratory, has conducted a smaller experiment 
in a small, partially isolated peach orchard during the present season, 
and was also able to determine the degree of infestation by the fruit 
moth in two other orchards in which bait traps had been maintained for 
comparisons of baits, as well as in a number of comparable unbaited or- 
chards. The reduction in injury appeared to be 47 percent in one or- 
chard, 77 percent in a second, and 78 percent in the third. This indi- 
_ Gates that a considerable degree of control of the fruit moth is possi- 
_ ble by baiting small areas. "The benefits from baiting on a small scale 
are not cumulative from year to year because of the extensive interor-— 
chard movement of moths. Continuance of the baits after harvest would 
be practical only where large areas are baited. Bait trapping as prac— 
ticed in one orchard would have cost the growers this season not more 
_ than $3.50 per acre, all expenses included." 
Low temperatures following woolly aphid attack cause !'die-back" of 
perennial canker.--M. A. Yothers, Wenatchee, Wash., summarized his ob- 
servations on the relation of the woolly. apple aphid (Eriosoma lanigerum 
Hausm.) to perennial canker of apple, as follows: "Accurate bimonthly rec- 
ords, in 1932, of woolly aphid infestation in some 300 3~year old calluses 
have given some rather definite results. In general it may be stated 
that: (1) Die-back, or extension, of perennial canker callus usually fol- 
lows prolonged and heavy woolly aphid infestation of the callus followed 
by severe winter temperatures; (2) die--back sometimes follows even milder, 
shorter periods of woolly aphid infestation followed by severe (zero or 
sub-zero) temperatures; (3) die-back of perennial canker calluses usually 
occurs only at points on the callus where woolly aphid infestation oc- 
curred the previous season; (4) the die-back of the callus is often of 
greater extent along the periphery than the previous extent of the woolly 
aphid infestation; (5) light or temporary (2 weeks or so) woolly aphid 
infestation is only rarely followed by die-back, or extension; (6) it has 
not yet been definitely established by the writer than the perennial 
canker organism is responsible for what is here termed 'die-back' of the 
