Pitch-Apple, Autograph-Tree, Rose-Apple, Balsam-Apple

Clusia rosea Jacq. with comments on C. major  and on “C. guttifera”

CLUE-see-ah  ROSE-ee-ah

Clusiaceae

Explanation of name: Clusius (Charles de l’Écluse, 1526-1609) was a botanist cited by Linnaeus. Rosea is self-explanatory.

Synonymy: There is confusion concerning the classification and nomenclature of the species usually called Clusia rosea Jacq. This is the name under which the species is usually referenced and marketed in contradiction to the discussion by taxonomists Woodson & Schery in the Flora of Panama (Ann. Missouri Bot. Gard. 67: 986, 987. 1980) who argued that the two are synonymous, making the correct name for the pair when treated as one Clusia major L., which DEH and other horticulturists have followed. Dr. Barry Hammel, Clusiaceae specialist at the Missouri Botanical Garden, communicates (pers. com. 8/05) that C. rosea is the correct name to use for the species in Florida, and that there has been an adjustment in lectotypification to lock in this usage formally. Material is marketed in Florida as “Clusia guttifera,” or “Small Leaf Clusia.”  Despite appearance among the wares of many nurseries, I (G. Rogers) to date (8/05) have failed to find a taxonomically valid publication or reference to this species name.

Natural range: In Florida, restricted naturally to Miami-Dade and Monroe counties (WU2); Caribbean Mesoamerica and South America. (Some authors suspect the tree to not be truly native; see discussion in NE2, p. 39.)

Recognition: Clusia species are dense-foliage trees with particularly thick, semi-succulent, leathery, obovate, opposite leaves. The sap is resinous, and the trees are prone to dangling adventitious roots that become stilt roots. The round flowers 2” in diameter are thick-textured and white and rose-colored.

            NE2 suggests the possibility of confusion between Clusia rosea and Seven-Year-Apple, Casasia clusiifolia (Jacq.) Urban. The latter, a member of the Rubiaceae, has only a superficial similarity in the leaf shape and differs substantially in many easily discerned ways, including by having stipules, by having clear sap, by having thinner leaves with curled margins, by having smaller flowers with just 5 (vs. more) petals, 5 (vs. more) stamens, and just 2 carpels, the ovaries inferior.

Landscape uses: Slow-growing, these tough salt-tolerant native trees are distinctive for their thick, dark-green foliage, and must be blended carefully with other vegetation. They screen out whatever is behind them and can be planted in rows, clusters, or even pruned hedges (see an example at the Horticultural Society of South Florida, Fern St., WPB). HAE and NE1 comment on aggressive roots.

Notes: Dwarf selections are marketed under the cultivar names ‘Nana’ and ‘Compacta’. UF IFAS Fact Sheet ST173 and NE1 describe cultivar ‘Variegata’. Clusias are dioecious, that is, they have separate male and female trees. The sticky sap has localized uses for caulking boats (BA2). In some settings the trees are epiphytes and stranglers, and can perch on the edges of rocks with the long roots extending many yards to the floor below. The fruits open into a dramatic multipointed white star containing red seeds.