Rust

Why turning rust leaves on the trees
paint wonder -- but not metal form,
the oxide scar, green metal bench?
Both witness chemicals at work;
the autumn auxin taking charge,
so damp air driving season’s cost.
A copper beech, the chestnut bract,
fall flaking branch, strip modesty;
yet next that picnic bench neglect,
with viridescent bottle mold,
its palette range a mirror work?
Would pristine tree in summer dress,
unchanging, satisfy our eye?
Why should our plant, this country seat,
not share the turning of the year?