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• All C. multijuga trees produce oleoresin. • Non-productive trees not produce oleoresin in sufficient quantities for storage. • Productive and non-productive trees differ in anatomy only by the vessels diameter. • The heartwood area, near the pith, stands out as the location of oleoresin storage. • The oleoresin is transported from secretory canal to heartwood vessel via ray cells. The objective of this study was to identify and describe differences in the anatomical structure of productive and non-productive trees of Copaifera multijuga Hayne, and to understand the anatomical basis for production and non-production of oleoresin. We also studied how oleoresin is produced, transported and stored. The study was carried out on a primary forest area (2° 57′ 43′′ South, 59° 55′ 38′′ West) and at a 33 year-old plantation (2° 35′ 51.28′′ South and 60° 02′ 10.57′′ West), both located near Manaus, Amazonas, Brazil. A total of 27 trees were selected, including productive and non-productive trees from both areas. Wood was sampled using destructive methods (3 trees in plantations) and non-destructivly (with 2 bores from 24 trees, each giving a 5 mm radial sample). Macroscopic analysis: samples were polished until all cellular elements could be seen, then examined under a stereoscopic microscope. Microscopic analysis: Semipermanent histological sections (15 μm thick) were made in the transverse, tangential and radial longitudinal planes. Sections were also made of macerated material. In general, anatomical observations made agree with previous published studies, and show similarities to other species in the genus Copaifera. With the exception of vessel diameter, which was always higher in trees with oleoresin production (Kruskal-Wallis: p < 0.001), no qualitative or quantitative anatomical differences were observed between productive and non-productive trees. Both types of trees had oil-containing cellular elements, including the marginal parenchyma cells, rays and vessels. However, the quantity of oil-bearing cells was much higher in productive trees. Secretory canals, present in the marginal parenchyma, were mostly unobstructed (without oleoresin). However, ray cells and vessels were always filled with oleoresin, suggesting that, although oil synthesis occurs in the secretory cannals epithelial cells, its transport occurs via the ray cells to the vessels, in the heartwood region, where it is stored. [ABSTRACT FROM AUTHOR]