14 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE, 1 
Miticides Compared in Orchards in Pacific- Northwest 
Mites on which acaricides were tested in the Pacific Northwest 
included the clover mite, European red mite, two-spotted mite, 
Pacific mite, and the yellow mite Tetranychus barealis Ewing. 
A minimum of % pound of L5-percent parathion to LOO gallons 
of wah'i' was accessary for good control of mites. Malathon gave 
a satisfactory control, but is somewhat less effective than parathion 
tit comparable dosages. EPN was fully as effective as parathion; 
Metacide somewhat less effective. Of the compounds tested which 
do not contain phosphorus, DMC (Dimite) was the most effective 
and long lasting. A single application in June controlled all 
)S for the rest of the season. P-ehlorophenyl p-chlorobenzene 
sulfonate (Ovotran) gave poor control of the Pacific mite, but 
excellent control of the other species. RV-242 (Sulphenone) gave 
limited control of the Pacific mite and yellow mite but satisfactory 
control of other species. It was particularly lethal to the preda- 
cious mite IphiduLus. Aramite, used at '-.and- - ') pintsto LOO gallons, 
did not control the diver mite or Pacific mite well, but gave good 
control of the other species. At 1 • L > or 2 pints it should give satis- 
ory control. CS-708 (Dilan) had little value against orchard 
mites but was very toxic to the predacious mites and insects. 
The appearance of resistant mites in the Yakima Valley provided 
an opportunity to investigate their control. A strain of the E 
pean red mite that had survived three application- of parathion 
was controlled with EPN. In small tests, i±o<n\ control was also 
obtained with Rr-242, Aramite. and p-chlorophenyl p-chlorobenzene 
sulfonate, the latter being particularly effective. A strain of the Pa- 
cific mite that had resisted parathion was effectively controlled with 
Aramite, and also succumbed to malathon and DM( . 
Plum Curculio Control Effective but Complicated by 
Objectionable Residues 
The outstanding insecticide testi gainst the plum curculio on 
peach in Georgia in L951 was dieldrin. This material gave a high 
degree of control in an unusually severe infestation, the experi- 
mental tree- being exposed to continual reinfestation from an adja- 
cent unsprayed block that was severely infested. Under these con- 
ditions, several other treatments that usually give satisfactory 
results fell down completely. Unfortunately, residues of dieldrin 
are now regarded as excessively dangerous, and a full schedule of 
this material will undoubtedly give objectionable residues. For 
reason it is likely that dieldrin can be used in only two or three 
early-season spray applications. In other Georgia experiments 
carried on in a moderately infested peach orchard, satisfactory con- 
trol was secured with dieldrin and several other materials, including 
parat hion, EPN, and aldrin. 
Tree Injur) Results in \\ ithdrawal of Recommendation for 
Peach Borer ( lontrol 
For the first time in 11 years of work with propylene dichloride 
emulsion for the control of the peach tree borer, injury t<> tree-. 
resulted from the recommended dosage of one-half pint of 
