Confusion about plant names
The origin of the oil can provide important information about its quality. But numerous oils also have names which can lead to confusion on the side of the customer. This is why it is so important to know the botanical name of the essential oil. Here are some examples:

• There is no relationship between the Atlas Cedar organic from Morocco and the Texas Cedar. The Texas-Cedar is not a cedar but a Juniper.
• The American Cedar Leaf oil stems in reality from a Thuya (Thuya occidentalis) and again has nothing to do with a Cedar.
• Spanish Sage oil (salvia lavandulifolia) is not the same as Salvia officinalis, the true Sage, and quite distinct in its chemotype and fragrance as well.
• Spanish Marjoram, also called wild Marjoram is actually a special kind of Thyme oil (Thymus mastichina) and is not the same as the true Marjoram  (Majorana hortensis), which is mainly distilled in France or Egypt.
• Spanish Lavender oils are usually the wild growing Spike Lavender containing cineol and are not the same as the true Highland Lavender oil (Lavendula officinalis) which contains more esters. The botanical name tells the truth.

Subspecies with different properties
Many essential oils like Rosemary Essential Oils, Basil Essential Oils, Lavender Essential Oils, Thyme Essential Oils, Sage Essential Oils, Eucalyptus Essential Oils etc. have subspecies which often exhibit very different fragrances and effects; this phenomenon is called 'biochemical polymorphism'

Eucalyptus dives or Eucalyptus Peppermint has very little in common with 'true' Eucalyptus (i.e. eucalyptus globulus), which itself is more similar to oils such as Niaouli or Cajeput.
Niaouli Linalol is more reminiscent of Rosewood or Ho-Oi than 'true' Niaouli (cineol type)
Thyme Geraniol is completely different to Thyme alpha-terpineol or Thyme Thuyanol etc.