This investigation was planned to study the new dormant spray, dinitro-ortho-cyclo-hexyl-phenol in relation to its use under Virginia conditions for the control of certain insects with which the Virginia orchardist has constantly to deal.

The object of this study is to determine what affects the varying amounts of dinitro-ortho-cyclo-hexyl-phenol, either in oil or water sprays with different emulsifiers, has on penetration, injury and effectiveness.

Conclusions which may be drawn from the work discussed in this thesis are: (1) That the 50 per cent goulac and 50 per cent bentonite emulsifier used at the rate of 1.25 pounds per 100 gallons is seemingly the best material among those tested. However, under the conditions in which trials were made this year, a dry form of dinitro-ortho-cyclo-hexyl-phenol mixed with an emulsifier containing bentonite and soy flour appears to be superior in preliminary tests, either in oil or water sprays, due to its better wedding power.

(2) That injury which has been examined apparently occurs at the bud and enters the branch through the bud.

(3) That the dinitro-ortho-cyclo-hexyl-phenol in oil and water sprays should be applied only in the dormant season, although no serious injury has followed its use in the plots used for this study even when the buds have pushed out leaves as much as one quarter of an inch.

(4) That in the plots treated, the powder and water form of dinitro-ortho-cyclo-hexyl-phenol gave satisfactory control of Rosy aphis.

(5) That time, care and the following of directions should not be sacrificed in the making up of the emulsions.