North American Fruit Explorers mailing list at ibiblio

[Scott Smith <scott@cs.jhu.edu>]

I have also found this  archive.org resource to be tremendous.  They  
have the underlying text recognized so you can search for keywords in  
the scans.  It makes  it very easy to find the page with e.g. a  
certain variety on it.  Some of the character recognition is not so  
accurate so it is not always working well, but often it is extremely  
helpful.  Also you can download the recognized text only in the .TXT  
links, which takes up much less disk space and download time.  The  
only downside is the scan file size, which besides making the  
downloads slow also makes for slow page changes  in your pdf viewer.

Here are a few others I found which Claude did not mention.  There  
are also many others you will find if you search for words such as  
apple, fruit, orchard and the like.

A guide to the orchard and fruit garden; or, An account of the most  
valuable fruits cultivated in Great Britain (1833)
Author: Lindley, George
http://www.archive.org/details/guideorchardfruit00lindrich

Elliott's fruit book; or, the American fruit-grower's guide in  
orchard and garden...
Elliott, Franklin Reuben
http://www.archive.org/details/elliottfruitbook00ellirich

A guide to the literature of pomology (1915)
Bunyard, Edward A.
http://www.archive.org/details/guidetoliteratur00bunyrich

American pomology. Apples  ([c1867])
Warder, J. A.
http://www.archive.org/details/americanpomology00wardrich

Scott