Those four were Callistemon forresterae, Callistemon genofluvialis, Callistemon kenmorrisonii and Callistemon nyallingensis which were regarded as being hybrids. The new description of Melaleuca has been accepted by some herbaria but not all. For example, the Queensland Herbarium accepts Melaleuca flammea (synonym Callistemon acuminatus) but the New South Wales Herbarium accepts Callistemon acuminatus. In 2012, Frank Udovicic and Roger Spencer transferred the newly described species of melaleuca with separate stamens (e.g. Melaleuca megalongensis and Melaleuca wimmerensis) to Callistemon (hence Callistemon megalongensis and Callistemon wimmerensis). Their argument is that using the DNA evidence is premature. They further argue that if all the genera Beaufortia, Callistemon, Calothamnus, Conothamnus, Eremaea, Melaleuca, Phymatocarpus were combined (as Craven has suggested), then there would be no characteristics that would define the group. Use in horticulture Many commercial nurseries continue to use the name ‘’Callistemon’’. These species can be propagated either by cuttings (some species more easily than others), or from the seeds. Flowering is normally in spring and early summer (October–December), but conditions may cause flowering at other times of the year. The obvious parts of the flower masses are stamens, with the pollen at the tip of the filament; the petals are inconspicuous (see picture). Flower heads vary in colour with species; most are red, but some are yellow, green, orange or white. Each flower head produces a profusion of triple-celled seed capsules around a stem (see picture) which remain on the plant with the seeds enclosed until stimulated to open when the plant dies or fire causes the release of the seeds. A few species release the seeds annually. Bottlebrush plants can be grown in pots. They have been grown in Europe since a specimen of Callistemon citrinus was introduced to Kew Gardens in London by Joseph Banks in 1789. Selected species There are about 50 species of callistemon. They include: Callistemon acuminatus Cheel – Tapering-leaved bottlebrush (also known as Melaleuca flammea); Callistemon brachyandrus Lindl. – Prickly bottlebrush (also known as Melaleuca brachyandra); Callistemon chisholmii Cheel (also known as Melaleuca chisholmii); Callistemon citrinus (Curtis) Skeels – Lemon scented bottle brush (also known as Melaleuca citrina); Callistemon coccineus F.Muell. (also known as Melaleuca rugulosa); Callistemon comboynensis Cheel – Cliff bottlebrush (also known as Melaleuca comboynensis); Callistemon flavovirens (Cheel) Cheel – Green bottlebrush (also known as Melaleuca flavovirens); Callistemon formosus S.T.Blake (also known as Melaleuca formosa); Callistemon forresterae Molyneux Callistemon genofluvialis Molyneux Callistemon glaucus (DC.) Sweet (also