S c e n t a s a n at t r a c ta n t
T
he smell of some flowers
Lonicera fragrantissima, winter honeysuckle
remains fondly in our
memories for many years and these memories are instantly
Those plants that produce
recalled when we smell the plant
scented foliage, mainly do so
again. Some plant smells are so
to deter grazing herbivores (see
strong that they can be overpower-
pp. 210–211). Scented foliage is
ing, and some plants produce
also found on many plants from
a fragrance that can only be
hot and dry climates, examples
described as disgusting! Small
include those used as culinary
wonder that it is plants that
herbs such as rosemary, basil, bay,
give us the world’s most
and thyme. As well as a means of
beautiful perfumes.
plant defence, these “essential oils” also play an important role
Most of the plant scents we
in protecting the foliage against
know and recognize are those produced by flowers. As with extravagant colors,
drought and subsequent desiccation. A layer of oil or
fragrance is mostly used in flowers to attract pollina-
oil vapor on or around the surface of a leaf serves to
tors, and in fruit to demonstrate ripeness. Volatile
reduce water loss.
compounds are produced, which readily evaporate. Different species contain different oils that combine together to produce the plant’s distinctive scent. One of the most abundant and volatile compounds is methylbenzoate. The scent of many winter-flowering plants can be very strong indeed. Garden favorites such as winter honeysuckle (Lonicera fragrantissima), Daphne bholua, and Christmas box (Sarcococca confusa) are well known; their scent is so strong because of the scarcity of pollinators in winter—they must advertise themselves as widely as possible to attract pollinators from far away.
Dictamnus albus (burning bush) is a good example of a plant that produces scented foliage. It is native to open habitats in southern Europe and northern Africa, and in hot weather it produces so many volatile oils that they can be ignited with a match, giving the plant its common name.