Catalpa x erubescens Carr. (= C. bignonioides x C. ovata) (Hort.) – An exceptional but possibly overlooked escape from cultivation. Recorded in relative abundance on a former railway yard near a coal mine heap in Beringen-Mijn since at least 2007 (but even then obviously present since quite some time). In this location subspontaneous plants of Catalpa x erubescens are freely flowering and fruiting. A recent naturalisation seems likely.
Possibly overlooked elsewhere as a result of confusion with Catalpa bignonioides and C. ovata. Young leaves are always dark brown to purplish and slightly lobed.
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