<jats:title>Abstract</jats:title><jats:p><jats:italic>Melaleuca leucadendra</jats:italic> L. (family Myrtaceae) exists in three chemotypes, the volatile leaf oil of two of which are characterized by very high contents of the phenylpropanoids methyl eugenol of E‐methyl isoeugenol (up to 99% and 88% respectively). In addition to small amounts of trans‐β‐ocimene and linalol, numerous sesquiterpenes, often in traces only, are also present in these two chemotypes. Limited progeny studies indicated that the methyl eugenol form might breed true whilst seed from the methyl isoeugenol form yielded a mixture of both chemotypes in approximately equal proportions.