Salicylaldehyde be prepared from the corresponding phenol by the Duff reaction, or by treatment with paraformaldehyde in the presence of magnesium chloride and a base. Salicylaldehyde was identified as a characteristic aroma component of buckwheat. It is also one of the components of castoreum, the exudate from the castor sacs of the mature North American beaver ("Castor canadensis") and the European beaver ("Castor fiber"), used in perfumery. Furthermore, salicylaldehyde occurs in the larval defensive secretions of several leaf beetle species that belong the subtribe Chrysomelina. An example for a leaf beetle species that produces salicylaldehyde is the red poplar leaf beetle
Castor Bay the bay, running towards the south. A small bark and grass area with several large pohutukawa trees offering shelter compliments the beachfront and an extended coastline stretches out to the north towards Campbells Bay. Nearby John F. Kennedy Park contains old World War II bunkers that were used to survey the Hauraki Gulf and is accessible from Castor Bay by road (Beach Road) or by walkway (from the extended coastline to the north). The northern headland of Castor Bay is the site of an old Maori pā, Rahopara, that is believed to have been last inhabited and then abandoned in