The Erland name didn't ring any bells - but I checked the 1900 Benton County census and here is the information on Sarah
ElDorado Township, page 110, house 86, family 87, enumerated 9 June 1900
Erland, Sarah, Sep 1852, age 47, widow, 9 of 9 children living, born in IL, parents in Norway, farmer; Oscar S., son, Jul 1877, 22, day laborer; Otto, son, Oct 1878, 21, farm laborer; Tilla B., dau, Feb 1881, 19; Portia G., son, May 1883, 17, school; Charley E., son, Mar 1887, 13, school; Chester, son, Jul 1888, 11, school; Clarence, son, Sep 1892, 7, school; Elmer, son, Jul 1894, 5
The interesting thing is that the census states all the children were born in Iowa - and both of their parents were born in Norway.
If Sarah's place of birth is correct - James M. Elson (he posts on this board) has more information on the Illinois Elsons.