Beth L. Bibby (i.e., Bethel Luc Burton Bibby), (30 June 1921 - 7 April 1984). Presumed proprietor of Beth L. Bibby Books, ABAA. Per the American Horticulturalist of August 1993 (vol. 72, no. 8), the firm was still in business under this name in 1993 and located at 1225 Sardine Creek Rd., Gold Hill OR 97525.
A mention in the gardening column of the Sacramento Bee on 29 July 1978 answers a question about “the largest second-hand garden book mail order company west of the Mississippi. It was located in Roseville [California], but I can't find it in the phone book. Can you help?” The columnist answers that Beth L. Bibby Books has moved to Gold Hill and sells “books on gardening, horticulture and natural history.”
The Business Minutes of the A.B.A.A. Annual Meeting of 27 April 1984 (as published in The Professional Rare Bookseller no. 7, 1984: 57) includes “Tribute to deceased members: Beth Bibby, Carl E. Houtchens, Warren Howell, Douglas Parsonage, Kurt Schwartz, and Donald Sharp.” Bibby appears to be buried in Hillcrest Memorial Park in Jackson, Oregon.