the essential oil of scleria hirtella was obtained by hydrodistillation and analysed by gc and gc-ms. the major constituents were nonanal (42.0%), geranial (25.3%) and neral (15.3%). it is a remarkable essential oil presenting a series of aliphatic aldehydes between c-7 and c-15, where the c-9 derivative is the most prominent. the aldehydes were probably generated from the oxidation of polyunsaturated fatty acids by plant enzymes. copyright (c) 2005 john wiley & sons, ltd.