Joseph Green, like his father and brothers was of an adventurous nature. He was only one year old when the family moved to Illinois and making a home out of the wilderness was surely an adventure. The expedition to the California gold mines in 1849, with his father and his older brother Jesse was a welcome change from his life in Dayton, which in twenty years had become much more civilized. Very much the little brother, he was eleven years younger than Jesse and although he would have considered himself, at 21, the equal of any man on the trip, he was still one of the younger ones. He was sorely missed in Dayton by his sisters, Rachael and Rebecca, who filled their letters with a wish that he would be home soon.

Most of the gold miners returned home in January of 1851, but Joseph and three others were left behind in Mexico, where they were to remain until spring, in charge of some Mexican horses which were bought in coming through that country.

Joseph had barely returned to Dayton when it became clear that his taste for adventure was still strong. His younger brother Isaac, who was deemed too young to go on the previous trip, wanted his chance and Joseph got up an expedition of his own to California, which left Dayton in April. As in the previous attempt, there were no great riches in the end, but the adventure may have been its own reward.

Joseph had expressed a desire to go to China, but this never came to pass, due to his untimely death, December 27, 1855, at the age of 27. He is buried in the Dayton cemetery