D. dadantii grow intercellularly, continuing to degrade cells and colonize, until it eventually reaches xylem tissues.

"Vital force theory" is a proposed mechanism for the ascent of sap through the xylem tissue of plants.

This causes the formation of galls that can grow big enough to restrict the xylem tissue inhibiting efficient water uptake by the plant.

These cells differentiate into xylem tissue.

The vascular cambium is active during growing season and produces a new layer of xylem tissue or growth ring every year.

As the stem ages the pholem tissue widens and can be found on both sides of the radial xylem tissue.

The ascent of sap in the xylem tissue of plants is the upward movement of water from the root to the crown.

If they land on the susceptible host they may enter through a wound and establish themselves in the xylem tissue of the host.

Such an infection is likely to impair the transport properties of the xylem tissue found at the center of the stem.

The fungus penetrates the plant's xylem tissue, digests it, and concentrates the nutrients on and near the surface of the beetle gallery.