The obscure scale, _Chrysomphalus obscurus_ (Comst.), is a pest of considerable importance, particularly in the more arid portions of the State. The tiny insect under its scale covering sucks the sap from the limbs and branches, causing them to lose their leaves and die back from the tips. The tree is so devitalized by the feeding of this insect that it is made vulnerable to attack by wood borers. The scale covering over a full-grown female is about one-eighth inch long and is usually dark gray, and closely resembles the bark of the tree. Infested limbs appear to have had wood ashes sprinkled over them, Figure 23. Numerous pits appear in the bark where the insects feed, producing a roughened appearance. [Illustration: Figure 23. Severe infestation of obscure scale on a pecan twig.] The winter is passed by the female scales under their coverings on the bark. Eggs laid in the spring hatch into tiny, salmon-colored crawlers which move about for a short time, then settle down and insert their beaks. While they are feeding, a scale covering develops which is made up of secreted wax and cast skins. The females never move again from the spot they have selected, but the adult males develop wings and emerge from their scale coverings to mate with the females. Only one generation is produced each year. _Control._—When damaging populations develop, a spray application of 3½ gallons of 97 percent miscible dormant oil per 100 gallons of water during the dormant season will keep this pest under control. _Application of Fungicides and Insecticides_ When possible, fungicides for disease control and insecticides for insect control should be combined in the spray tank and applied to the trees in one operation. The spray materials should be applied evenly and thoroughly to all the leaf and nut surfaces to provide a chemical barrier to disease organisms and insects. Do not neglect the tops of the trees. Diseases and insects can harbor and multiply in all unsprayed areas of the tree. Thorough coverage with spray materials is essential for effective control. As a guideline, apply approximately 1 gallon of spray mixture for each foot of tree height. Apply 20 gallons to a 20-foot tree and 40 gallons to a 40-foot tree, etc. _Spray Equipment_ Various types of spray machines for application of fungicides and insecticides to pecan trees are available. The spray machines employ either a high pressure hydraulic pump, high pressure centrifugal pump or low pressure high air velocity systems. All the machines are portable and are equipped with a gasoline engine or operate from a truck or tractor power takeoff shaft.