Wadis may refer to dry or wet riverbeds. Dry wadis contain water only during times of heavy rain, while wet wadis are characterized by a series of pools of water and the occasional palm grove located on either side. Plants of note include: Adiantumcapillus-veneris, Fimbrystilisferruginea, Nerium oleander, Phragmitesaustralis, Saccharumravennaeand Typhadomingensis.