A bat can eat 3,000 mosquitoes in one night. Leave that dead tree in place. Birds will glean insects hiding under and in the bark. Brush piles and rock walls attract rabbits, snakes, voles, birds, and mice. A thicket of berry-bearing shrubs is a bird magnet, and provides cover for lots of species.
Evergreen trees provide excellent cover in wet and windy weather.
Deciduous trees provide food and homes for birds, squirrels, and insects. A bird bath isolated in the center of turf grass is not very attractive to nervous birds always on the lookout for predators. Generally, animals don't feel comfortable crossing open spaces. Place feeding areas close to shrubs and wildflowers, and plant vegetation around pools and ponds. Remember that small plants grow-leave enough space for plants to mature.