Notes on Tilia platyphyllos

Tilia platyphyllos Scop. (Finland, Espoo, Kalajärvi, 2003). – Photo: Harri Harmaja.	Tilia platyphyllos Scop. (Finland, Lohja, Jalassaari, 2004). – Photo: Harri Harmaja.

Three escaped occurrences of the cultivated broad-leaved lime (Tilia platyphyllos Scop.; Tiliaceae) has been found by me in southern Finland. Two occurrences in Espoo were found by me in 1990, and one in Lohja in 2002. The plants of Lohja are seedlings from a cultivated near-by tree. The direct source of the Espoo stands, two of which are among normal forest vegetation, is more difficult to trace but most probably they are seedlings that somehow were established here due to the adjacent forest road to a near-by, now abandoned rubbish dump; a few other escapes occur in the area.
    Only a few literature reports exist about T. platyphyllos having escaped from cultivation in Finland. Woody Flora of Finland (Hämet-Ahti, L., Palmén, A., Alanko. P. & Tigerstedt, P.M.A. 1992: Suomen puu- ja pensaskasvio. 2nd ed. – 373 p. Dendrologian seura r.y. Yliopistopaino. Helsinki.) gives escapes in two bioclimatical provinces in Finland (Ahvenanmaa and Etelä-Häme), and Flora of Helsinki (Kurtto, A. & Helynranta, L. 1998: Helsingin kasvit. Kukkivilta kiviltä metsän syliin. – 400 p. City of Helsinki Environment Centre & Helsinki University Press. Helsinki.) found the species as a casual escape in a few wasteland habitats in Helsinki (prov. Uusimaa). The Botanical Museum (H) of the Finnish Museum of Natural History contains specimens of escaped individuals, a few of of them from forest habitats.
    The nearest indigenous occurrences of T. platyphyllos are in SW Sweden and Denmark. Maybe this species (like some others of southern provenience) is nowadays more apt to get escaped from cultivation than previously. If this is true, the warming of the climate may be considered as one explanation: southern species may produce more viable seeds and/or be more competitive within the native vegetation.

Description of the occurrences of escaped Tilia platyphyllos

1) Varsinais-Suomi. Lohja, Jalassaari, Heimo. The occurrence was observed as late as in 2002; it cannot have got rise earlier than the 1990’s. It comprises some seedlings, of which the oldest are roughly ten years old. The habitat is a park-like rich wood on somewhat calcareous soils near a house, at 20-50 m distance of the parent tree which was planted about 1925-1935.
2) Uusimaa. Espoo, Kalajärvi, not far from the nature reserve ‘Tremanskärr’. Two near-by occurrences: (i)) Young trees or bushes, oldest ca. 20-30 years old, in rather oligotrophic fairly undisturbed forest, consisting of a) one stand near highway ’Porintie’ with 10 individuals in mesic mixed woods (a specimen was collected by me from this stand on 30.VI.1990), and b) another stand of 13 individuals in grass-herb woods at a distance of about 30 metres of the preceding stand, on the other side of the small forest road. (ii) Some hundred metres away from the preceding occurrence towards the forest: two trees, some dozens of years old and approximately 40 m apart from each other,  at the disturbed, now bushy, margin of an abandoned rubbish dump now covered with soil.

Created March 17, 2004. Latest revision May 13, 2004.