Ochagavia elegans Phil.
Literature references:
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- An Introduction to an Under-cultivated Bromeliad by Paul Wilkin
0chagavia has the most southerly distribution of the genera of the Bromeliaceae with the exception of Fascicularia. It is found in coastal and montane sites in central Chile as far as 39° South, while Fascicularia is restricted to coastal southern Chile (Smith & Downs, 1979). The two genera appear closely related: they are most easily distinguished by their sepals, which are ecarinate and acute or acuminate with an apiculus or small apical mucro in Ochagavia and obtuse or rounded and carinate in Fascicularia.
The relatively temperate region in which Ochagavia is found makes it one of the hardiest genera of bromeliads, though the genus is not widely cultivated. Of the three species of Ochagavia recognised in Smith & Downs (1979), O. carnea (Beer) L.B. Sm., from mainland Chile, is encountered occasionally in cultivation, and is included in Rauh's (1979) extensive manual on bromeliads. A photograph of an individual of this species grown at Kew was included in the Journal of the Bromeliad Society (anon. 1979); sadly, this plant has since died. Only two other articles on Ochagavia have been in published in the Journal of the Bromeliad Society: one on the nomenclature of O. carnea (Foster, 1956), and the other two paragraphs in a wide-ranging review of Chilean bromeliads (Rauh, 1986). Thus, this is a genus in need of greater attention.
Ochagavia elegans Philippi is endemic to the island of Masatierra of the Juan Fernandez Archipelago, and has been collected rather infrequently. It is a caulescent terrestrial bromeliad of suffruticose habit, forming extensive colonies on exposed slopes and rock faces, even those of vertical aspect. The stems of plants collected in the wild can grow to over 1 m long, and the older leaves die on the basal part, leaving a mass of brown leaf sheath and vascular tissue remains, among which adventitious roots arise. These roots probably act to anchor the plant on unstable rocky substrates. The many recurved-spreading, thick, leathery leaves are polystichously arranged along the apical part of the stem, rather than forming a rosette as in O. carnea, and the vental leaf surface has a dense covering of pale grey scales (figure 1). O. elegans inhabits strongly insolated sites with little soil or water, and thus is somewhat xeromorphic. Like the other species of Fascicularia and Ochagavia, the apical inflorescence is scapeless and sunk in the centre of the leaves, with the flowers in a flat, dense, subcorymbose arrangement. Some of the leaves immediately surrounding the inflorescence are reduced in size and often purple-hued and bract-like (figure 1). Unlike O. carnea and O. chamissonis (Mez) L.B. Sm. & Looser, which have inflorescences surrounded by a dense involucre of rose-pink or blood red bracts, Ochagavia elegans lacks true inflorescence bracts. The inflorescence is densely subcorymbose and relatively flat, while those of the other two species are more globose in shape.
It is in floral morphology that the main differences between O. carnea and O. elegans are encountered. Each flower is subtended by a 35-48-mm long, obovate to oblong floral bract, with a pungent apex and spinulose-laciniate margins. The bracts are lepidote like the leaf ventral surfaces, but less densely so. The flowers are short-pedicellate, and consist of a 21-26-mm long ovary and a 10-14 (-19)-mm long epigynous tube at the apex of which the sepals, petals and stamens are inserted. The tube does not exceed 5 mm in the other species of the genus. The sepals are 16-18-mm long, free, narrowly ovate-triangular, chartaceous, especially towards the margins, and have a few fine marginal teeth, while the petals are 18-28-mm long, free, erect, obovate and violet-pink to dark purple in colour (figure 2), darker than that of O. carnea, This floral colouration and the presence of the relatively long epigynous tube suggest that hummingbirds may be the vector of pollination in this species, though experimental tests of this hypothesis are required. The slightly exserted position of the stamens, which are 19-25-mm long, also supports the hypothesis of bird-pollination. The style is 38-43-mm long and slightly exceeds the stamens, and the stigma is trifid. The fruits set by the plants in the field are indehiscent, coriaceous and apparently rather dry; their means of dispersal is unclear. They contain many globose seeds at maturity. The plant grown at Kew appeared to set fully formed seed, but Skottsberg (1953) reports that the plant he grew did not. Its vigorous offset production suggests that reproduction in O. elegans is probably predominantly vegetative, rather than sexual.
The plant now being grown at Kew was germinated from seed in 1987 and established in a vertical rock crevice in the Alpine Glasshouse. It was severely damaged by frost in 1990 when the heating failed, but fortunately some of the buds near the stem base were unharmed and it regenerated and flowered freely in June 1993 (figures 1 & 2). It is not hardy, and a cool, well ventilated, frost-free greenhouse is probably ideal for its cultivation in the UK, though if grown in a pot it would probably benefit from being placed outside in the summer and would thrive in mild coastal climates like those of Masatierra. The related Fascicularia pitcairnifolia (Hort. ex Verlot) Mez is grown in sheltered gardens in the extreme southwest of Britain. O. elegans is easily propagated from its prolific pups, which are simple to root, and need little attention or feeding. Indeed, the key to flowering O. elegans in cultivation seems to be restricting root growth. Skottsberg (1953) described sowing seed in 1918 and 1919, which germinated freely and grew well, but failed to flower in an open bed in a succulent house. He finally flowered a cutting in a small pot in 1944. Perhaps the gravest threat to this extremely attractive bromeliad in cultivation is other gardeners; the single offset on the plant when it was in flower in the Alpine Glasshouse disappeared one weekend in spite of the presence of security cameras! —See J. Bromeliad Soc.
- Figures. Fig. 4-5; Skottsberg, Nat. Hist. Juan Fernilndez 2(7): 110, fig. 5. 1922, id. 6(29): 868, fig. 27, pl. 97. 195J;Smith&Downs 1979: fig. 490; Zizka in Palmengarten 2/1992: 103, fig. 10. 1992; Wilkin 1996: pl. 287; Danton 2002: fig. 4.
Vernacular name. - Ajo dulce, ajo verde, chupon.
Remarks. - Forming extensive colonies on steep ridges. The flowers appear to be typically ornithophilous. Skottsberg ( 1928) gives a detailed description of the flowers (flowering time: October to May) and reports the hummingbird Sephanoides fernandensis visiting the flowers. He also discusses the seed dispersal of the species and suggests endozoic distribution by the only frugivorous bird native to the island, Turdus falcklandii.
Further references. - Philippi in Bot. Z. 14: 647. Sept. 1856; F. Philippi in Anales Univ. Chile 59: 278. 1881; Baker, Handb. Bromel.: 19. 1889; Johow, Estud. FI. Juan Fernandez: 149. 1896; Reiche, Grundz. Pfl.-Verbr. Chile: 67. 1907; Skottsberg, Nat. Hist. Juan Fernandez 2(7): 110. 1922, id. 4( 18): 526. 1928; Harms in Engler & Prantl, Nat. Pflanzenfaill., ed. 2, 15a: 159. 1930; Smith & Looser in Rev. Univ. (Santiago) 18: 1077. 1934; Mez in Engler, Pflanzenr. 100: 204. 1935; Skottsberg, Nat. Hist. Juan Fernandez 6(28): 774. 1951,6(29): 867. 1953; Munoz, Espec. Pl. Descr. Philippi: 35. 1960; Smith & Downs in Fl. Neotrop. Monogr. 14(3): 1529. 1979; Marticorena & Quezada in Gayana 42: 81. 1985; Hoffmann & Flores in Benoit, Red List Chilean Terrest. Pl.: 119.1989; Zollner & Oyanedelin J.Bromeliad Soc.41: 169. 1991; Wilkinin Bot. Mag. 13: 24.1996; Danton in Bull. Mens. Soc. Linn. Lyon 68(5): 107. 1999.
HABITAT - Rocky, cxposed cliffs; 200-600 m elevation. Reported by Skottsberg (1953).to grow exceptionally also epiphytic. Gajardo ( 1995) lists Ochagavia elegans as one of the "especies acompanantes" of the Cuminia fernandeziana - Azara fernandeziana and the Stipa neesiana - Polypogon chilense communities.
- Chile, Juan Fernandez archipelago, endemic to Isla Robinson Crusoe (Fig. 3), —See Zizka et al. 2002
