In Central NY where I have experience, any buck older
than 1-1/2yrs, with spike antlers would be considered
a trophy in most areas, simply because they would be
so rare. While 1-1/2yr old bucks carrying their first
antlers are commonly spike bucks.

Populations above the carrying capacity often have
larger percentages of spike bucks, for several
reasons. Mainly, late born fawns, due to a drawn
out rut, because all does in estrous are not serviced
the fist time around. Then, nutrition -in a large herd
faced with small resources, fawns are the last to eat the
more quality browse, and it shows in body weight and
antler growth the following fall. Also, deer that are
overpopulated are "stressed", and have poor fawn survival
rates, poor antler growth, and lower body weight - EVEN
when supplied enough food to meet all there needs. This
was proven in the Cusino Study and others.

Genetics rarley figure in when discussing spike bucks.
In 20 years of hunting, I've never seen a cowhorn spike,
that was not in fact a 1-1/2yr old deer. A couple freinds
have, but they were 2-1/2 yrs old, and not any older. 10"
spikes in my area, are fairly common as 1-1/2 yr olds.

Genetics are much more likely to be an issue when considering
top end antler growth. For example, areas in Maine, Florida,
and many other states rarley produce B&C bucks, even where
hunting pressure is light.