VANCOUVER, British Columbia, Jan. 16 (UPI) -- Canadian researchers have discovered how pine and spruce trees fight pests and disease, providing new information about forests' natural defense systems.

University of British Columbia Associate Professor Joerg Bohlmann and colleagues said their genetic analysis will allow forest stewardship programs to reinforce a forest's inherent strength -- breeding trees that could in time repel insects such as British Columbia's notorious mountain pine beetles.

Bohlmann and research associate Christopher Keeling explored the genetic makeup of oleoresin within spruce, discovering a sophisticated ability to produce complex blends of chemicals that continuously evolve to protect the tree from changing conditions and challenges.

"Conifers are some of the oldest and longest living plants on the planet," said Bohlmann. "We've opened the book to understanding how they can survive in one location for thousands of years despite attacks from generations of insects and diseases."

The research is reported in the Proceedings of the National Academy of Sciences.