Where Birds Eat
Consider your backyard in three levels.
The top level is the trees. Their nests are usually high in trees and they're usually insect eaters, filling their bellies with the caterpillars and insects they glean from the foliage. Tanagers, orioles, vireos, warblers, cuckoos, and grosbeaks are top level feeders.
The middle level is shrubs, tall grasses and flowers. Its for birds like cardinals, catbirds, thrashes, wrens, sparrows and some warblers that like cover that's not too high off the ground.
The ground level area is your lawn and garden beds. That's the area in your yard for birds that prefer to pull worms or grubs, scratch in the leaves for insects, or pick up seeds. Robins and grackles on the lawn are ground-level birds. So are the blackbirds, thrushes, sparrows, junco, quail, pheasants and towhees that you may have noticed.
Your bird feeding goal is to fill all three levels of your backyard with treats for the birds. So, plant trees - even when the trees are young, they'll attract the insects that birds enjoy. Plant a variety of shrubs to re-create a natural hedgerow and let some areas of grass or annual flowers grow thick and undisturbed. Sparrows and other ground feeders will do fine on your lawn, in a meadow garden, or under shrub plantings in a shady garden.