the book was published in 1950 and likely hard to find, I know the Minneapolis downtown library has it
they have combined it with his book "A Natural History Of Western Trees" into one book called "A Natural History Of North American Trees" and is available at most libraries in MN
It is available as a download from Dakota County Library (MN), I'm not sure if reciprocity allows you to download. It looks like if you register at Hoopla, you will be able to download
register here is a link to the library, search for it and you could try a download
third book down=
few people have heard of this guy today, he died 50 years ago, but was quite popular in his day as a nature writer