No.. just aim the light at the road in front of you, not into the trees..
[my most used: Schmidt E6 halogen, and SON dyno-hub]

the beam is directed, and so I just point it appropriately,at the road,
though, it does light up reflective signs quite a ways away.

bright helmet light when you direct your eyes and thus the light
at oncoming drivers, I think may be an issue.