Hi, What is this pest I found in my evergreen? Should I worry about it? How to get rid of it? Thanks.
The insects in the photo you provided are mealybugs. These small sucking insects cover their bodies with a white, cottony substance which is what makes them easy to identify. Mealybugs are a type of scale insect that feed on the sap of both indoor and outdoor plants. Female mealybugs often gather in dense numbers. Mealybugs get their name from the powdery waxy layer that they produce for protection as they feed. These pests can damage trees & shrubs by sucking out their sap. They also excrete a honeydew which when produced in great amout encourages the growth of sooty mold, and attracts other insect pests. The insects overwinter on plants as eggs within white cottony masses. The eggs hatch in the spring, and the nymphs feed on leaves and young stems.
Mealybugs can be difficult to control. Your first line of defence is to physically remove as many adult females from the shrub as you can by spraying with a hard blast of water from your garden hose, and then picking off or crushing any adults that remain behind. You can also apply an insecticidal soap, carefully following the manufacturer’s instructions. Mealybugs can spread to other plants and trees, so be sure to monitor the rest of your garden carefully.
The following links provide additional information on the proper control of this pest: Mealy Bugs on Yews
With constant monitoring and proper integrated pest management you will be able to control this pest.