Abstract

Seedling anatomy and cross sectional discs of 8- and 12-yr-old (juvenile) teak trees in plantations at Nilambur, Kerala, India, were examined for growth ring analysis and determination of environmental factors responsible for false ring formation. Based on the anatomy and location within the true annual rings, 4 types of false rings were identified. The results from both cross-dating of plantation grown trees and controlled experiments, including induced drought, showed that rainfall during dry periods, drought during the active growing season, (container) polybag/field transplantation of seedlings and juvenility are the important causative factors of frequent false rings in teak. No definite relationship could be established between insect defoliation and the incidence of false rings. False ring formation in teak appears to be mainly a resultant feature of growth ring responses to different environmental and physical factors