Rhamnus (its ancient Greek name). Including Frangula. Rhamnaceae.
Buckthorn. Ornamental woody plants grown chiefly for their handsome
foliage and some also for their attractive fruit.
Deciduous or evergreen shrubs or small trees, sometimes spiny: lvs.
alternate or opposite, short-petioled, with small deciduous stipules,
penninerved, serrulate or entire: fls. small, in axillary clusters,
umbels or racemes, perfect, polygamous or dioecious; sepals, petals and
stamens 4-5, petals sometimes wanting; style usually undivided; ovary
2-4-loculed: fr. a globular or oblong 2-4-seeded drupe; nutlets with a
leathery usually dehiscent wall.—About 100 species native chiefly to
the temperate regions of the northern hemisphere. A few species are
found in the tropics and as far south as Brazil and S. Afr. Several
species yield yellow or green dyes and the frs. and bark of some are
used medicinally. The wood of R. Frangula is made into charcoal valued
for the manufacture of gunpowder.
The buckthorns are handsome shrubs with generally bright green often
rather large leaves and with inconspicuous greenish flowers usually in
axillary clusters followed by berry-like, usually black, rarely red,
fruits. Many of the species as R. cathartica, R. dahurica, R. fallax,
R. Frangula, and R. alnifolia, can be depended upon as hardy, while R.
Purshiana and R. lanceolata are hardy at least as far north as
Massachusetts. R. imeretina and R. caroliniana are somewhat more
tender. The handsomest in foliage are R. fallax and R. imere- tina and
the evergreen R. ilicifolia and R. crocea. R. Purshiana, R.
caroliniana, R. alnifolia, R. dahurica, and R. Frangula are also
noteworthy on account of pretty foliage. Of the evergreen species which
are not hardy North, R. crocea and R. ilicifolia are to be recommended
for their ornamental bright red fruits. Buckthorns are useful for
planting in shrubberies: they like a rather moist soil, especially R.
lanceolata, R. alnifolia, R. caroliniana, and R. Frangula, and grow
well in shaded or partly shaded situations, but R. cathartica and its
allies prefer dry soil. R. cathartica is a valuable hedge plant, though
it is now not used so extensively as in the past. The species are
propagated by seeds stratified or sown in fall, and by layers. Some, as
R. lanceolata, R. fallax, and R. alnifolia, are propagated by cuttings;
R. Purshiana, has been successfully raised in England from softwood
cuttings put in mild bottom heat under glass about the middle of July.
The evergreen species are propagated by cuttings of ripened wood under
glass. Rarer kinds are sometimes grafted, those of the Frangula group
usually on R. Frangula and the true buckthorns on R. cathartica or
allied species.
The above text is from the Standard Cyclopedia of Horticulture. It may be out of date, but still contains valuable and interesting information which can be incorporated into the remainder of the article. Click on "Collapse" in the header to hide this text.
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