from
The Collaborative International Dictionary of English v.0.48
Pruner \Prun"er\, n.
1. One who prunes, or removes, what is superfluous.
[1913 Webster]
2. (Zool.) Any one of several species of beetles whose
larv[ae] gnaw the branches of trees so as to cause them to
fall, especially the American oak pruner ({Asemum
m[oe]stum}), whose larva eats the pith of oak branches,
and when mature gnaws a circular furrow on the inside
nearly to the bark. When the branches fall each contains a
pupa.
[1913 Webster]