Submitted to: Pecan Grower
Publication Type: Trade Journal
Publication Acceptance Date: 2/16/2004
Publication Date: 3/15/2004
Citation: Cottrell, T.E. 2004. Scale insects on pecan. Pecan Grower. v. 15:16-17. Interpretive Summary: Interpretive Summary: Many species of scale insects are found to attack pecan. The predominant species found attacking pecan across the southern US is the obscure scale. Populations of this scale on pecan can be economically damaging and should be controlled. At least two applications of dormant oil (2%) applied to runoff is most often required to adequately manage this pest.
Technical Abstract: Insect control in pecan orchards typically focuses on those pests that are apparent and cause noticeable economic damage. However, there are other pests of pecan that somehow slip through the cracks of pest management programs. Included in this category are the scale insects. As a group, scale insects are very diverse and attack a wide range of host plants. On pecan, scale can be found on limbs throughout the canopy and also on trunks. The obscure scale (Melanaspis obscura) is commonly found on limbs. Dormant oil sprays (2% oil) applied at rates to provide runoff are necessary for management of scales with oil. It is important that the scale be entirely covered with the dormant oil as death is not by contact but rather by suffocation. Application volumes suitable for control of pecan weevil with contact insecticides are too low for control of scale insects.