I assume that between the two maple trees is quite shady and, of course, there is much competition for moisture from the maple trees. This is a very difficult place to grow Kentucky Bluegrass. Look for grass seed mix that does well in shady and is drought tolerant. This will be the fine fescue grass varieties. Here is a link to much more information: https://extension.umn.edu/lawn-care/buying-turfgrass-seed-minnesota-lawns

By the way, spring is the best time for seeding fescue varieties to get them through winter. An alternative to grass might be to grow a shade tolerant ground cover such as periwinkle. 

Paul -Master Gardener volunteer