The invention provides methods of engineering plants having lignin deposition or xylan deposition that is substantially localized to the vessels of xylem tissue in the plant. The invention also provides methods of engineering plants to increase production of a desired biosynthetic product, e.g., to have increased secondary cell wall deposition or increased wax/cutin accumulation. The engineered plants of the present invention have use in bioenergy production, e.g., by improving the density and the digestibility of biomass derived from the plant and to improve water usage requirements.
STATEMENT AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT
 This invention was made with government support under Contract No. DE-AC02-05CH11231 awarded by the U.S. Department of Energy. The government has certain rights in this invention.