Ratib al-Jubrour, the coordinator of a local committee against settlements and the wall, said Israeli soldiers looked on as the settlers torched the field belonging to Khalid Mousa Najjar.
Najjar was shot by settlers in 2002, al-Jubrour added.
On Sunday morning, Palestinians from nearby village Susiya found seven piles of harvested grain had been torched in a field near an Israeli settlement.
Settlers also destroyed dozens of olive trees in Yatta on Sunday, al-Jubrour said.
In the West Bank, over 90 percent of villages which have experienced multiple attacks by settlers are under Israeli security control, The Palestine Center says, meaning local Palestinians only have the official protection of an army which they claim ignores settler violence.