Assuming wet snow on the wings of a highwing (Taylorcraft in this
case),

Because of the presence of the struts, I'm trying to visualize if the
spars would be hurt by the weight.

I've viewing the strut attach point as a pivot point. Assuming an even
distribution of snow, the moment around that point would be zero and
no harm done.

are there other forces I should take into account? - Mike

PS - she's tied down so if snow slipped off one wing, the tie-down
would prevent excessive tipping.