and their relation to resting periods
*
Diagram IV. (detail, inverted; some scale/legend info removed)
one of six diagrams showing starch storage in rubber trees for the period November-June, thus completely covering the wintering period.
ex L. E. Campbell, “Seasonal variations in the storage of plant-food in Hevea Brasiliensis and their relation to resting periods.”
Department of Agriculture, Ceylon, Bulletin No. 22. (September 1915)
Pennsylvania State University copy (issues 21-30 bound together), digitized September 18, 2010