Cedar Sensation

What am I looking at?

This is a cross section of a young shoot on a cedar tree (a member of the genus Juniperus). The web-like pattern radiating from the center of the image is created by the cell walls of xylem cells (1). The structure at the center of the image is the pith (2). The pith’s role is the storage and distribution of nutrients throughout the tree. The three vascular, or pith, rays (3) are responsible for radial conduction of water, minerals, and nutrients. And the orange ovals are grains of starch (4), where the plant stores energy.

Biology in the background

True cedars are native to the mountains of the Mediterranean and the Himalayas and are not found in the Americas. However, there are relatives of true cedars that are native to the Americas, such as juniper and cypress trees; these are commonly referred to as “cedar trees,” even though they strictly speaking aren’t cedars.

All of these tree are conifers – meaning they reproduce via pine cones. They are well adapted to mountainous terrain and can survive in fairly cold temperatures for extended periods. One reason for this is that they are densely packed with sap that acts as antifreeze during the winter and keeps the trees hydrated during the summer. This sap also helps produce the characteristic cedar smell, which is used in cosmetics and essential oils and is also useful in deterring certain types of insects, including moths.

Currently, the largest cedar tree in the world is the so-called Duncan Cedar in Washington State. It is 54 meters (178 feet) tall and nearly 6 meters (about 20 feet) wide.

Technique

These images were created using confocal microscopy.