Shoot and root vulnerability to xylem cavitation in four paopulations of Douglas-fir seedlings. DeBell, J.D., B.L. Gartner, and D.S. DeBell. Fiber length in young hybrid populus stems grown at extremely different rates. Spicer, R. and B.L. Gartner. Gartner, B.L. 1997.
Trees have higher longitudinal growth strains in their stems than in their roots.
Wood density patterns of young Costa Rican trees in planted and natural forests. M.S. Robbins, J. M. 2000. M.S. DeBell, J. D. 1998. Ph.D. Spicer, R. 1997.