>what is the common components b/w 
> natural plant resins and asphalt?
 
Asphalt/tarmac/macadam "cement" is made from residues from the distillation
of crude oils.  You heat it to mix it with the aggregate (small pebbles and
such).  To make it mix and "spread" smoothly, you add petroleum distillates
like naptha or kerosene to thin out the gooey tar-like cement.  After
spreading, the naptha/kerosene evaporate out slowly, the mix cools, and the
tarmac solidifies.

Naptha and kerosene have a sharp top-note in their odor, similar to pine
tree resin.  Volatile organic compounds, I dunno which ones.  My >>
unverified speculation << is that when you create a strong odor plume by
heating the stuff up, the bees notice.  This explains why bees are attracted
to freshly-laid tarmac, but never to old road edges.  Once the stuff cools
down, it stops being a source of VOCs.  So, can bees be attracted to
warmed-up kerosene for bee-lining purposes?  I have not tried this.

In a similar manner, bees are reliably attracted to a water source with a
slight agitation at the surface, produced with a fish-tank aerator.  The
water vapor in the air is the "odor plume" of a water source.  Go ahead and
laugh at this, urban bees get into more trouble over unfortunate choices of
water sources than anything else.

The recipe for asphalt is something I actually learned in school.  Everyone
in any engineering field takes some civil Engineering classes.  It seemed
boring at the time, but the Civil Engineering instructor was so amazingly
polite...

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