Thanks to FGI BOTM alum Carlos Diaz for notifying the govdoc-l list about a new resource from the National Agricultural Library (quote edited for URL formatting):

Looks like the NAL has begun to digitize in .tiff format their historical collection of publications including the Agriculture handbooks and yearbooks, etc.

You can find the Digital Repository at http://naldr.nal.usda.gov/

A very precious resource indeed.

We agree. The digital repository has publications going back many decades for the following series:

Agricultural Economic Report
Agriculture Handbook
Agriculture Information Bulletin
Bean Improvement Cooperative Annual Report
Bean Improvement Cooperative Natl Dry Bean Res Assoc Conference
Division Pomology Bulletin
Economic Research Service Staff Report
Fruit Vegetable Market News Report
Pomological Watercolors
Report Commissioner Agriculture
Report Secretary Agriculture
Rural Development Perspectives
Rural Development Research Report
Technical Bulletin United States Department Agriculture
World Poultry Congress
Yearbook United States Department Agriculture

Some monograph publications and other non-series publications are also available. The documents are a touch awkward to use though. You need to page through them one page at a time. But if you use their "print pdf" button, you can get a PDF file for your use. Another nice feature of this site is an RSS feed and list of recent additions.

Finally the repository can be searched. Results include not only matching publications, but also specific page numbers. Results can be sorted by the column headings, very nice!

Naturally I used "Alaska" for my search. It brought up hundreds of results, including this tidbit from the 1958 Agriculture Yearbook:

Creator        Johnson, Hugh A.    
Title     Seward's folly can be a great land.    
Source     Yearbook United States Department Agriculture    
Year     1958    
Volume_Info     1958    
Pages     p. 424-439.

Go and check out this resource. And then remember that it was a LIBRARIAN who brought it to you! Thanks again, Carlos!