Although I do not have a death date nor can tell you anything specific about Joan Gerardus KLAUS, I can provide you with some information about his wife and two of his children.
The maiden name of Mrs. Catherine KLAUS is WEIDMIER.I have seen her name spelled in various ways including WEDERMEYER and WEDEMYER.
The 1900 Federal Census (Nicolaus Township, Sutter County, CA) lists her husband as Julius H. ERICH.I do know that this is the right family though.Besides the ERICH children, Joseph KLAUS (listed as stepson, born March 1862) is also in the household.The age for Julius ERICH (age 55, born December 1844) does match the August ERICH found in the 1880 Census with Catherine.
Catherine died in Sutter County on 25 May 1911.Julius ERICH died in Napa County on 20 June 1929.I found him in the 1920 Federal Census at the state hospital in the town of Napa.
Henry KLAUS died in Napa County as well, on 12 April 1927.Records for Henry have been difficult to find, but I did locate him in Butte, Sutter County, California in 1920.He was single and worked as a hired hand.
Katherine KLAUS (1867-1942) became the wife of Charles Ernest BARTHE (1870-1921).They had one daughter, Marie Jeanette BARTHE (1901-1968).I do not believe that Marie ever married.After the death of Charles, Katherine and Marie moved away from Yuba County.Both Katherine and Marie died in Contra Costa County.
I also have some information on the ERICH children.Please let me know if you are interested and I'll pass along what I have found.I do know that at least two of the ERICH children are buried in Marysville City Cemetery in Yuba County.I suspect that Mrs. Catherine ERICH is buried there as well.