Adam Clarke on 1 Chronicles 2:54

The sons of Salma - "The righteous Bethlehemites, who had a good name, as the Netophathites, who removed the guards which Jeroboam had placed in the way lest the people should carry the first-fruits to Jerusalem: for the sons of Salma carried baskets full of first-fruits privately to Jerusalem; and having cloven wood, they made ladders, and brought them to Jerusalem to be laid up in Beth-mokad for oblations. These came from the lineage of Joab the son of Zeruiah; and some of them were priests; and they divided the residue of the sacrifices with the sons of the prophets who were in Zorah." - T.