disease serve as factors of environmental change. This is magnified in areas that are not prone to large-scale dynamic disturbances like wildfires or are dominated by old-growth timber. In older-growth forests, trees are unable to combat heart rot effectively because they grow at a much slower pace. Extensive rot causes these trees to be more susceptible to high winds and trunk fracture. As the old growth dies out, it allows new growth to take its place, altering the dynamic of the environment. Decaying trees and tree hollows also provide shelter to animals as well as microorganisms. Through this process of dynamic change, heart rot contributes to biologically diverse habitats. Prevention and control The prevention of heart rot can be a very difficult task, but there are effective measures to minimize damage. These methods include facilitating healthy growth, minimizing wounds, and proper pruning of branches. A healthy tree naturally combats heart rot through a process called compartmentalization. The tree grows around the decayed wood tissue and prevents the fungus from spreading to a larger area of the trunk. Providing a tree with the necessary nutrients, water, and growing conditions will promote healthy growth and minimize rot. The bark is the tree's main defense against disease; reducing the amount of large wounds and bare wood, especially in older trees, helps prevent rot. Pruning techniques Pruning focuses on removing dead or diseased branches with minimal damage done to the tree. Branches connect to the trunk and grow from the branch collar. While the branch itself may be dead, the branch collar is still healthy and resistant to disease. It is from the branch collar that a new limb will generate and grow, so it is important not to damage it while pruning. Make clean cuts at the base of the branch adjacent to the branch collar. Small branch stubs (larger than three inches) will inhibit the growth process and provide fungi with ideal growth environments. Examples The following are some trees susceptible to heart rot: Alder Aspen trunk rot Spirostachys africana References External links Picture of a tree with heart rot The heart rot fungus Fungal tree pathogens and diseases