"It may briefly yet categorically be stated here that the earliest book of the Aryans, viz. the Rigveda, does not mention any of the species of cold-climate trees... On the other hand, all the trees mentioned in the Rigveda, such as the Asvattha (Ficus Religiosa L.), Khadira (Acacia catechu), Nyagrodha (Ficus benghalensis), to name just a few, do not belong to a cold climate but to a tropical one."