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Cover Illustration: Cross section through the xylem of Freycinetia arborea Gaudich (‘ie‘ie) aerial roots stained with a saturated solution of Phloroglucinol in 20% aqueous HCl. Lignified cell walls stain red-to-orange. The differences in staining intensity are due to differences in cell wall thickness and degree of lignification. This was a cryosection from the outer part of the xylem. The aerial roots were harvested form the Manoa Cliff Trail above the Manoa Valley on Oahu. Root pieces were evacuated overnight in a solution of 10% DMSO, 4% paraformaldehyde, 1% Tween 80, 0.05 M cacodylate buffer, pH 7.4. Explants were sectioned at −20°C at 40 μm, stained immediately and photographed on a Zeiss Universal microscope with Ektachrome ISO 100 film. These roots are used by Hawaiian Islanders to make fine baskets and as an extremely strong cordage. (Image courtesy of David Webb.) For more information on phloroglucinol staining of lignin, see Phloroglucinol Stain for Lignin (doi:10.1101/pdb.prot4954).