1. An inability to clear the land (16:1-17:13)
Joseph's portion was actually two portions given to the tribes of his two sons. They too needed to claim their inheritance and dislodge pagan nations. At times, they were unable to do what the Lord commanded (16:10; 17:12). The remaining Canaanites were subjected to forced labor. We are not sure why they could not dislodge them. This caused problems for these tribes in the future.
2. God blesses, with our obedience (17:14-18)
The people of Joseph felt they needed more land. But their enemies had iron chariots. They had a different attitude than Caleb. Joshua acknowledged their strength and granted them more land, but the people would have to clear it, which meant driving out the Canaanites.