Wikipedia
Carmichaelia (New Zealand brooms) is a genus of 24 plant species belonging to Fabaceae, the legume family. All but one species are native to New Zealand. The exception, Carmichaelia exsul, is native to Lord Howe Island and must have dispersed from New Zealand.
The formerly recognised genera of Chordospartium, Corallospartium, Notospartium and Huttonella are now included in Carmichaelia. The Carmichaelia, Clianthus (kakabeak), Montigena (scree pea) and Swainsona genera comprise the clade Carmichaelinae.
Carmichaelia have a range of forms from trees to prostrate species a few centimetres high. Mature plants are usually leafless, with stipules fusing into scales to replace leaves.
Carmichaelia is named after Captain Dugald Carmichael, a Scottish army officer and botanist who studied New Zealand plants.
Carmichaelia is distributed throughout New Zealand although the eastern South Island has 15 species endemic to it. Most species have a restricted range within New Zealand. They colonise disturbed ground in shallow, poor soils, drought- and frost-prone areas and alluvial soils.
New Zealand broom is not closely related to the European species Cytisus scoparius, common broom, which has been introduced to New Zealand, where it is commonly known as Scotch broom and is classed as a noxious weed because of its invasiveness.