Dieback Disease of Pines with Special Reference to Corsican Pine, Pinus Nigra var. Calabrica schn.

Publisher Website
Google Scholar
Abstract
In north Yorkshire the earliest symptoms of disease appear at the base of the bud in January. A small area of tissue in the region of the lowest leaf primordium becomes necrotic, the protoplasts being damaged and the cells filled with resin. This stage is revealed externally by bleeding of fresh, clear resin on to the outer bud scales. From the bud the necrosis extends into the shoot and into the needle bases. Buds of the lower branches are the most susceptible, the disease proceeding upwards through the crown and usually killing only current year shoots. An analysis of distribution of disease reveals that north-facing slopes are heavily infected while trees on south aspects are generally vigorous and healthy. A distinction is made between dieback disease which occurs in poorly ventilated, sheltered stands and debility resulting from exposure, or from nutritional disorders.

This publication has 0 references indexed in Scilit: