SteveB wrote:
....
Yes. IOW, in a lot of places, they used what they had. This was
particularly true on the first coast to coast railroad. I would be
interested in the exact number of different tree species used for those.

I suspect there's no way to know and probably wasn't known at the time,
even.

In railroad ties, to a real old railroad person, I'm sure that there would
be a list starting from the best to the worst, yet sometimes they used the
worst for lots of reasons. It was close, cheap, etc.

And wouldn't gauge (width) of the wheels dictate the lengths of the ties?

For standard line ties, of course. There are a multitude of other
lengths as well for special purposes such as switchpoints, etc., of
course. A standard rail tie these days is nominal 8' 6" (or at least
was when I was sawyering and are what the ones I have are, which are
roughly 30-yr of age now, being left over from the truckload we bought
when first built the lots).

Now, unfortunately, often the railroads use the big rippers that go down
the center of the track and split them in two and simultaneously roll
the tie and rail to each side of the roadbed before laying new seamless
rail--consequently used ties the traditional way of buying them from the
railroad and going and picking them up along the right-of-way where they
were being replace is getting pretty hard to come by here. My pile is
down to only a couple dozen so I've been keeping my eyes open but
nothing has shown up yet...

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