Jennifer M. Withington, Peter B. Reich, Jacek Oleksyn, and David M. Eissenstat. 2006. Comparisons of structure and life span in roots and leaves among temperate trees. Ecological Monographs 76:381–397.

Appendix D. Cross sections of first-order Acer pseudoplatanus and Picea abies roots showing presence of endodermis.

FIG. D1. (A) Cross-section of a first-order Acer pseudoplatanus root stained with 0.05% phloroglucinol. The xylem and the thickened walls of the exodermis are stained red, and the latter is marked with an arrow. (B) Cross-section of a white first-order Picea abies root stained with 0.05% phloroglucinol. The exodermis is stained red and marked with an arrow.