Who does not know the lavender's perfume so characteristic of the Provence?
The lavandin presents a better yield in essential oil that is used mainly
in perfumes and cosmetics, but also in washing powders and cleaning materia
ls. The chemical and thermal study, made on the same stalk of the lavandin,
during the period from January to August, responds to two goals. First for
economic appearance, we observed a higher yield of essential oil in open o
r wilted flowers. The automation of the flowers gathered has induced a decr
easing of the essential oil in distillation, on account of the recovery of
the branches without oil. Moreover, the water, mineral ashes, cellulose, li
gnin, holocellulose, and hemicellulose contents are computed in all the aer
ial parts (new and old leaves, branches). Second, the wild lavender, like o
ther plants of the land of Provence, could be at the start of the forest fi
re. The inflammability risk can be observed by thermal analysis at about 30
0 degrees C: presence of an exothermic peak by DTA, weight loss by TG, and
determination of the maximum decomposition rate by differential thermogravi
metry (DTG). In high-heating rates (about 50 degrees C/min), the decomposit
ion of the aerial parts of the plant increases mainly with the cellulose le
vel. (C) 2000 John Wiley & Sons, Inc.