Return to Skip Menu

Main Navigation

Return to Skip Menu

Main Content

Why don’t trees ‘bleed’ when injured?


   

3-D microscopic cross-section of pine Featured on the cover of the American Journal of Botany, this image depicts three bordered pits in a 3-D microscopic cross-section of pine, with cellulose shown in green and pectin in red.


May 15, 2014 – Professor Barry Goodell and his colleagues from the Virginia Agricultural Experiment Station; The Jackson Laboratory in Bar Harbor, Maine; and Georg-August University in Gottingen, Germany, discovered how “check valves” in wood cells control sap flow and protect trees when they are injured. Their work was featured on the cover of the American Journal of Botany. Thanks to a powerful new type of microscope, scientists can now see nanostructures in wood fiber cells in a more natural state.

A tree’s fluid sap passes from one cell to the next through nanostructures called bordered pits. Each pit contains a mesh of cellulose fibers that radiates out from a thickened, solid, central region called the torus — looking somewhat like a bull’s-eye in a target. Fluids ooze through the mesh- like membrane, around the torus, and out the other side.

The scientists have discovered how some of the nanostructures of the membrane move with the torus to seal off the pit when wood is damaged or is being dried, which helps explain how trees seal off their cells so that they don’t “bleed to death” or lose all their sap when they are injured.

Read the full press release.


25th Anniversary

Celebrating 25 Years

    1992 through 2017, 25 years

Join us Sept. 15-16 to visit campus and reconnect with alumni, faculty, staff, and friends.

Celebrate with Us

Read the Summer Newsmagazine

    CNRE Newsmagazine Spring 2017


Select a Major

We have 11 majors for you to choose from with over 10 options to specialize in. Select yours now and join us in bringing the future to nature.