Admirers frequently note the striking white bark of quaking aspen. This bark lives and carries ... (dioecious), unlike the majority of tree species, which support both male and female reproductive ...

of cutting off the tree's nutrient supply. "These beetles are the biggest mystery," says Worrall. Before SAD, aspen bark beetles were known to science, but "most entomologists who worked on aspen ...

it looks like a forest made up of individual trees with characteristic white bark and small leaves that move even in the lightest breeze. It's a 43-hectare complex of quaking aspen clones ...