Odd Landscaping

It's springtime in the mid-south and flowers are beginning to bloom in our yard. We were quite shocked when we saw what a plethora of plant life we have growing in our jungle of a backyard.
Some are coming up in the middle of the lawn.

While others are growing through the rail-road ties that separate the "lawn" area from the "foresty" area.

And we are still trying to figure out what the previous owners of the house were doing when they planted this in the middle of the yard. It is almost a perfect rectangle and then dotted in the middle with random plants. I have tried standing on the roof to see if from the sky it forms a word or picture, but it dosen't seem to.