A Technical Report from The Bartlett Tree Research Laboratories 399
Brown spot needle blight causes needle browning and defoliation of many pine species in North America. The disease is most common on longleaf, ponderosa, and Scots pine, but can affect most pine species growing in dense plantings with limited air movement and sunlight penetration. Small trees and lower branches on large trees are the most commonly affected. Young longleaf pine is particularly susceptible due to its unique growth habit (grass stage). Repeated defoliation can lead to branch death, decline in health, and tree mortality.