more... > Pecan Research & Extension Center > Plant Pathology > When should fungicide applications for control of pecan scab disease begin? A frequently asked question about pecan disease control is, “When should the first fungicide application on my pecan orchard begin each year?” This is an important decision, and not always one with an easy answer. Following is a discussion that should help in making the yearly decision on when to begin the pecan fungicide application program. Pecan Bacterial Leaf Scorch [Image: Large native pecan tree in Natchitoches Parish, La.] For more than two decades there was uncertainty about the cause of a common disease among pecan trees referred to as leaf scorch. LSU AgCenter researchers were able to distinguish the cause of the disease, which has improved pecan production. Pecan Bacterial Leaf Scorch: Cultivar Susceptibility and Pathogen Transmission [Image: Pecan Bacterial Leaf Scorch on a Cape Fear tree.] This article is a copy of a paper presented at the National Pecan Scientists Meeting in Branson, Missouri, in July 2005. It discusses pecan cultivar susceptibility and transmission of the Pecan Bacterial Leaf Scorch pathogen in pecans. Procedure for Hot Water Treatment of Pecan Scion Wood [Image: Pecan Bacterial Leaf Scorch on a Cape Fear tree.] This document provides a step-by-step procedure for hot water treatment of pecan scion wood to eliminate the bacterial leaf scorch pathogen.  more articles... Pecan Scab Disease [Image: Pecan Scab Disease] Pecan scab disease is the most economically damaging disease of pecan production in the southeastern United States. The disease affects stem, leaf and nut growth, causing reduced yield. This publication includes information on the development, symptoms and control of the disease. (PDF format only) Fungicide Application Recommendations for Pecan Disease Control [Image: Air-blast sprayer] The key components of the effective use of fungicides for pecan disease control are timing, coverage and concentration. The updated 2012 fungicide list is included. Pecan Disease Synopsis [Image: Scab lesions on nuts] This document describes the diseases that occur most frequently on pecan trees in Louisiana.