In my neighborhood in Minnesota, I just discovered a small group of trees that I haven't seen before. Attached are pictures of the leaves and fruits growing on the trees, as well as of the nut inside the fruit. The outside of the fruits had small spikes/thorns. The flesh inside the fruit was somewhat spongy with a uniform thick-and-tough-bread-like texture. The trees were about 20 to 25 feet tall. The trunks were about 8 inches in diameter. I don't remember how the leaves were arranged on the branches, and I don't currently have any other pictures of the trees. Does anyone know what kind of tree this is?