Opuntia ammophila Small 1919

Publication : The prickly pears of Florida in Journal of the New York Botanical Garden 20(230): 29 (-30), pl. 224 (février 1919).

Description

Buisson plus ou moins érigé de 1-1,20 (-2)m de haut, à troncs distincts et branches divergentes, mais parfois aussi prostré sans tronc distinct. Articles plats vert clair à foncé, brillant à glauques, obovés, à elliptiques ou ovales (allongés et presque cylindriques pour les troncs), de 3,8-17,2cm de long sur 3,8-6cm de large.
Aréoles portant 0-1 épine, parfois 2, la deuxième alors nettement plus courte, de couleur rougeâtre, devenant grises avec l'âge, de 2-6cm de long, souples, et de longs glochides denses. Feuilles en cône allongé de 6-10mm de long, dressées puis recourbées vers le bas, caduques.
Floraison diurne au printemps (fin avril-mai en Floride). Fleurs jaune brillant, de 5-8cm de diamètre. Bourgeon floral pointu à segments extérieurs du périanthe charnus, étroitement acuminés ou lancéolés, recourbés vers l'arrière. Segments intérieurs du périanthe obovés à extrémité généralement très proéminente et apiculée, bien que ce caractère puisse être moins marqué.
Fruits pourpres, obovoïdes, de 2-3cm de long. Graines lenticulaires de 4-5mm de diamètre.

Description originale:
"4. Opuntia ammophila Small, sp. nov.
Plant erect, more or less branched, throughout or ultimately with a stem 1-2 m. tall or more, becoming 1-2.5 dm. in diameter, bearing several spreading branches near the top, thus tree-like, tuberous at the base: joints various, those of the main stem elongate, ultimately fused on the ends and subcylindric, those of the branches typically obovate or cuneate, varying to elliptic or oval, thickish, 0.5-1.7 dm. long, becoming gray-green: leaves stout-subulate, 6-10 mm. long, green: areolae relatively numerous, conspicuous on account of the densely crowded long bristles, especially on the older joints, the marginal ones, at least, armed: spines very slender, solitary or 2 together, reddish or red, at maturity gray, mostly 2-6 cm. long, nearly terete, scarcely spirally twisted: flowers several on a joint: sepals lanceolate, acute or slightly acuminate: buds sharply pointed: corolla bright-yellow, 5-8 cm. wide; petals cuneate or obovate, notched and prominently apiculate, scarcely erose: stigmas cream-colored: berries obovoid, 2-3 cm. long, more or less flushed with red-purple, many-seeded: seeds about 4 mm. in diameter. [Plate 224.]
Inland sand-dunes (scrub), peninsular Florida.- Type specimens from south of Ft. Pierce, collected in December, 1917, by J. K. Small. They are in the herbarium of the New York Botanical Garden. Living plants are also in the conservatories of the Garden, as well as in the plantation at Buena Vista, Florida.
My attention was first attracted to this species on the large sand-dunes south of Fort Pierce, in a region that has turned out to be the southern end of its geographic range. It reaches its best development, however, in the northern part of its range west of Lake George. It differs from all our other species in the gray-green color, the numerous elongate, very slender, often deflexed, spines, and in the small, thick-obovoid fruits. In spite of its vicious armament, the cattle that range through the country west of Lake George often browse upon it.
This plant is the most conspicuous native prickly-pear in Florida, and curiously enough, in proportion to its striking habit, the most neglected one. It is confined to the so-called "scrub" or inland quiescent sand-dunes which range in a general way through the lake region and the east Florida flat-woods, from the region west of Lake George to that east of Lake Okeechobee.
The first definite record of Opuntia in Florida begins with the record of the discovery of a large prickly-pear about the western shores of Lake George by William Bartram in the latter part of the eighteenth century.1 His account of the plant he observed suggests a form with the habit of Opuntia Ficus-indica; but this species could not have been established there at that early date, and, further, he describes the berries as purple and charged with juice. One could imagine that he found a plant or a colony of the plant just described; but its fruits are conspicuously small, at least relatively so in proportion to the size of the plant, and they are not particularly juicy, in fact they are rather dry.
The writer recently visited the country west of Lake George, traveling many miles through it for the purpose of rediscovering the Bartram plant, but without success. If Bartram did find a particularly smooth and large-fruited prickly-pear, such as he describes, the cattle may have exterminated it by this time. Thus the Bartram Opuntia still remains a mystery.
1 Travels through North and South Carolina, Georgia, East and West Florida 161."

Type: J.K. Small 8456., U.S.A., Floride, 6 miles au sud de Fort Pierce, St. Lucie Sound, dune à buissons, 20 décembre 1917, conservé au New York Botanical Garden (holotype: N.Y.).

Culture

Plante inconnue en culture amateur. Culture probablement facile sans grandes particularités par rapport aux conditions générales de culture de la famille des Cactaceae.
Reproduction par bouturage d'articles, voire par semis.

Etymologie

Opuntia: origine incertaine: voir la fiche de genre.
ammophila: du grec ammos, sable, et philein, aimer: qui pousse dans le sable.

Habitat

U.S.A.: Floride.

Anecdotes

Nom vernaculaire: scrub prickly-pear.

Exposition

Vive (luminosité maxi, plein soleil accepté)

Température mini

8°

Arrosages

Hiver : Aucun. Eté : Moyen.

Substrat

Standard (3 tiers)

Dimensions maximales

Hauteur : 2 m. Largeur : 1 m.

Couleur des fleurs

jaune

Auteur

philippe (contacter)
Fiche créée le 01/04/2006.