I'll second MikeM's somewhat educated guess with my somewhat educated guess that it was former temporary war housing and/or former temporary war manufacturing space. It's mind boggling looking at aerial photos of the city just after the war how much temporary housing and manufacturing was crammed in on seemingly every last bit of unbuilt land. Mound and Van Dyke were loaded with it on the east side all the way past 8 Mile. The west side had its fair share along the Sfld Fwy as well. A lot of the linear developments became the boulevarded highways we have today. Many of the larger contiguous parcels became public housing.