Chamaecyparis Spach
Chamaecyparis is a small genus of five closely related species in eastern Asia and North America. Its boundaries have slightly changed in recent times, as a result of molecular phylogenetic studies (Little & al. 2004): two species with leaves without white markings are now accommodated in a separate genus, Xanthocyparis (see there). In addition to the single species below, at least two other taxa of Chamaecyparis s.str. are cultivated in Belgium, both natives of Japan: C. obtusa (Siebold et Zucc.) Endl. (syn.: Cupressus obtusa (Siebold et Zucc.) K. Koch) and C. pisifera (Siebold et Zucc.) Endl. (syn.: Cupressus pisifera (Siebold et Zucc.) K. Koch). These might escape as well but juvenile plants of Chamaecyparis are usually hardly identifiable in the absence of obvious parental trees. So far, only Chamaecyparis lawsoniana has been recorded with confidence as an escape from cultivation in Belgium. The few records of other escaped taxa of Chamaecyparis require confirmation.
Literature:
De Koning J., Van den Broek J.W., Van de Laar H.J. & Fortgens G. (2000) Nederlandse dendrologie (13e druk). H. Veenman & zonen, Ede: 585 p.
Farjon A. (2005b) A monograph of Cupressaceae and Sciadopitys. Kew Publishing: 648 p.
Little D.P., Schwarzbach A.E., Adams R.P. & Hsieh C.-F. (2004) The circumscription and phylogenetic relationships of Callitropsis and the newly described genus Xanthocyparis (Cupressaceae). Amer. J. Bot. 91(11): 1872-1881.
Michener D.C. (1993) Chamaecyparis. In: Flora of North America Editorial Committee (ed.), Flora of North America north of Mexico, vol. 2. Oxford University Press, New York-Oxford: 408-410.
Mitchell A. (1986) Chamaecyparis. In: Walters S.M. & al. (eds.), The European Garden Flora, vol. 1. Cambridge University Press, Cambridge: 83-84.
Roloff A. & Bärtels A. (2006) Flora der Gehölze (2e Auflage). Ulmer, Stuttgart: 844 p.