|
''Hieracium lachenalii'' also known as common hawkweed or yellow hawkweed is a species of plants in the dandelion tribe within the sunflower family. It is native to Europe but has become established as a weed in Australia and parts of North America. The species was widely known for many years as ''H. vulgatum''〔(Flora of North America, ''Hieracium vulgatum'' Fries, 1819. )〕 but more recent studies indicated that the two names represented the same species. The name ''H. lachenalii'' was coined in 1802,〔(The International Plant Names Index, ''Hieracium lachenalii'' )〕 ''H. vulgatum'' in 1819,〔(The International Plant Names Index, ''Hieracium vulgatum'' )〕 so the older name is to be used.〔 (International Code of Nomenclature for algae, fungi, and plants (Melbourne Code), article 11 )〕 ==Description== This common weed can grow and produce flowers on plants that range from 4 inches (10 centimeters) to 36 inches (90 cm) tall. The rhizome is short and stout. The broadly elliptic leaves can be up to 5 inches (12 centimeters) long and taper with teeth towards the base. Each flower head has 40-80 ray florets but no disc florets〔 〕 Bracts surround the flower head; the receptacle (basal part of the flower on which the florets are attached) is flat and naked; heads tend to start together then become somewhat solitary on long leafless stems.〔 The stalks below the heads are covered with scattered, simple and gland-tipped black hairs and contain a milky substance.〔 The pale yellow flowers are produced during all of the summer months. The fruit are dark brown achenes.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Hieracium lachenalii」の詳細全文を読む スポンサード リンク
|