Chimonobambusa

Comments:

(1) Only one species of Chimonobambusa is recorded to be a native of Thailand: Chimonobambusa armata. Occasionally found cultivated in northern Thailand is Chimonobambusa quadrangularis, which might have been introduced a long time ago.

(2) All species of Chimonobambusa have a monopodial type of rhizome; the culms form a grove. The species that are naturally grown or planted in northern Thailand can become more or less invasive.

(3) A few other species of Chimonobambusa have recently been introduced and planted in the cooler hilly areas of northern Thailand, but their survival in cultivation is not confirmed. The seedlings have turned out to be difficult to get established at elevations below 400 meters. They might thrive well in the tropics and subtropics on specific sites at elevations of 900 meters and above. None of the seedlings survived at Bambusetum Baan Sammi, Chiang Mai (altitude 305 m).

(4) The species identification of the introduced seeds labeled as "Chimonobambusa" or "Qiongzhuea" species could not be carried out successfully. Seeds were obtained in a total of 10 species names of the genus Chimonobambusa (syn. Qiongzhuea, Oreocalamus). There is no doubt that the seeds represent the genus Chimonobambusa, but identification of the species was not possible because there are only minor morphological differences in the seeds, there is no documentation on the seed morphology available for comparison, and none of the seedlings could be grown to mature plants, which would have been necessary to see their characteristics.

(5) I suspect that some of the seeds were obtained under incorrect species names and that they are not 10 species, but fewer. This assumption is supported by three indications: Firstly, the seeds were collected over a period of 5 years (2010-2014) from flowering plants within China. Each of the species has a relatively small, mountainous distribution range. It is unlikely that 10 different Chimonobambusa species will flower more or less simultaneously within 5 years. Secondly, although the flowering cycle of the individual species may not be well known, Chimonobambusa species are known to flower quite rarely. Examples of flowering cycles: Chimonobambusa quadrangularis in excess of 100 years, C. szechuanensis 70–80 years, C. utilis ≈40 years (T. H. Wen, Taxonomy and Cultivation of Chimonobambusa Makino, J. Amer. Bamboo Soc. 11 (1-2), 1994 [#1176]). Thirdly, out of the 10 species under whose names seeds have been obtained, 3 are represented, of which neither flowers nor seeds are known, and investigations in July 2020 regarding the presence of evidence of a flowering event of those species remained unsuccessful.