I searched this free site for upstate NY papers, and found a death notice for Silas. It doesn't say where he is buried, but it answers the question of why he went to Nebraska. Click on St. Lawrence County, then choose search all papers
http://news.nnyln.net/

The Free Press, Gouverner Ny Feb. 1, 1899

Forward- At the home of his daughter, Mrs. Robt. Powers of Eustis, Frontier County Neb, Silas Forward January 30, 1899 suddenly of heart failure age 69 years.
A native of Pinkney Lewis County, and for many years a resident of St. Lawrence County.


It looks like Robert and Ruth Powers were back in St. Lawrence County by 1910.