How to know what wood was used to construct our attic? Need to know how much load it can tolerate

framing

I'm reading a book and it lists different max loads for different woods.
It lists loads for (1) Douglass Fir-Larch and (2) Hem-fir
My attic is made with a dark brown wood. How do I know what type of wood was used to construct the attic?

The house was built in 1939 in Southern California (don't know if this helps to identify it)

Here's a picture of the attic. (Could it be redwood?)
enter image description here

Best Answer

It is not redwood it looks like fir. At the age of the house almost the wood was fir back then. Nice tight grain like what you have is almost impossible to purchase now unless you just won the lottery.