Citronnelal and the Horsefly

As you know I live in Shakespeares country.  The river Avon ambles by and is fed by numerous slow moving streams.  Warwickshire is home a lot of horses.  In some villages horses outnumber the human residents!  In the first week of July the horseflies go on the rampage attacking horses and humans alike.  So the question is what is the best source of citronellal to keep off the pesky horseflies?  A bite is not only painful it can lead to large swellings and reactions in humans.

Eucalyptus citriodora essential oil is a rich source of citronellal (80%) and is reported to be non toxic, non-irritant and non-sensitising so can be used on the skin. 

Other less favoured sources of citronellal are Lemongrass (cymbopogon c.) and Lemon Tea Tree (Leptospermum petersonii). Lemongrass can be irritating and sensitising in some individuals. Tea tree is possibly sensitising in some individuals.  Tea tree left in clear glass rapidly oxidises with para-cymene content increasing from 3% to 30% enough to cause chemical burns.  Tea Tree left in amber glass hardly oxidises.

It works on mosquitos as well.

Essentia