What natural foods does bird food mimic?
Seeds, nuts, fruits, berries and insects in all life stages, flower nectar, sap, leaf and flower buds are among the natural foods available to birds seasonally or year-round.  The foods in our feeders should resemble those natural sources.

Ground-feeding birds such as Dark-eyed Juncos and other sparrows east vast quantities of weed seeds.  At your Feeders, these birds prefer White Proso Millet, Cracked Corn, and other grains high in carbohydrates.  Since their natural foods are very low in fats and proteins, they must eat constantly to get all the nutrition they need.

Perching and tree-dwelling Songbirds that find most of their food above ground seek out foods with a balance of fats, proteins, and carbohydrates.  These birds prefer Sunflower Seed, Nyjer, Peanuts, and Fats.

GUIDE TO THE FOODS WE SHOULD BE OFFERING AT OUR FEEDERS

SUNFLOWERS SEEDS: The Main Course
Sunflower seeds mimic the seeds of trees including pine hemlock, spruce, fir, maple, elm and beech.  Plus, flower seeds of all sizes.
TYPES:  Premium Black Oil Sunflower (screened to eliminate most of the sticks and stems) - it is preferred by birds because it has a high oil content (50% more calories than Striped Sunflower) and thinner shells, easier to open.
STRIPED SUNFLOWER - Larger seeds and harder to open.  Helps keep away the Sparrows and Starlings (they can not open the shells).  Easily opened by Cardinals, Blue jays and Woodpeckers.
SUNFLOWER HEARTS OR CHIPS (no shell):  Fine chips are used in Finch Feeders, Whole and Medium Chips are used in mixes

and alone.  Easier for birds to eat and NO MESS beneath the feeder or on your deck.

SAFFLOWER
Those darn squirrel !  Those pesky Blackbird and Starlings !  I want more CARDINALS...
Safflower comes in 2 varieties:  White (harder shell) and Nutrasaff (golden brown)
Similar in size to a sunflower with similar amounts of fat, protein and calories.  EXCELLENT PROBLEM SOLVER WHEN USED ALONE IN YOUR FEEDER.  Blackbirds, Starlings and most squirrels do not like it.  Cardinals, Chickadees, Morning Doves and House Finches like it.  More expensive than Sunflower, but economical in the sense that squirrels and undesirable birds are not eating it.

WHITE PROSO MILLET
Dark-eyed Juncos in the winter, Chipping Sparrows in the summer, and many other ground-foraging birds year-round.  Millet is a grain that mimics small native flower and weed seeds such as ragweed, buckwheat, crabgrass, smartweed and chickweed.  

If you offer Nyjer, you have an excellent chance to attract the beautiful American Goldfinch.  It is sometimes called "thistle", this seed does not come from native or invasive thistles.  It is a member of the aster flower family, with pretty yellow flowers -  and does not spread.  Most Nyjer is grown in Ethiopia and India.  Since it is imported, Nyjer is treated with dry heat to sterilize any noxious weed seeds that might be a threat to agriculture.  Nyjer has a thin shell and is vulnerable to spoiling in the tube if moisture is present.  Finches are picky eaters, and prefer fresh seed.  You should replace every 3-4 weeks if it is not eaten in your feeder.  If the seed gets molding in your feeder, rinse with a 10% bleach solution, rinse it thoroughly and dry before refilling.  If you have old seed in storage, lay it out on a newspaper and pound with a hammer, if oil comes out, seed is good.  My favorite seed is a custom mix we sell at Wild Bird Connection- Thistle & Chips (mixture of Sunflower Fine Hearts & Nyjer Seed).

PEANUTS
Birds constantly seek out high-energy foods, peanuts are a high calorie food, second only to Sunflowers.  Only offer unsalted peanuts.  Peanuts, in or out of the shell mimic acorns and pine nuts.  Several species of birds, especially BLUE JAYS cache great numbers of acorns. Loved by Blue Jays, Woodpeckers, and Nuthatches.
TYPES:  Peanuts in the Shell - Huge hit with Blue Jays and Woodpeckers.  Peanut pieces - Peanuts out of the shell, great no waste, no mess food.

SUET
Woodpeckers are the most consistent patron, but many insect-eaters are attracted to fat (suet).  The best suet for birds is a high-quality rendered beef kidney fat. Rendering kills bacteria and removes moisture.  It is important to use a high quality suet, birds will ignore the lesser quality suet cakes.
TYPES:  SUET CAKES - Adding ingredients to high-quality suet increases protein and nutritional value.  Peanuts, peanut butter, nuts, sunflower hearts, and insects.  The more protein added - the higher quality, and they will cost more.
SUET PLUGS (logs) - Same quality as cakes, but shaped to fit into Suet Log Feeders.  Favorite of Woodpeckers.

MEALWORMS
Mealworms are the larvae of non-flying beetles.  Mealworms are usually offered as a treat.  Some birds survive mainly on insects in the summer, such as Wrens.    Year-round insect eaters like Woodpeckers, welcome these treats.  Good idea to mix with your seed blends,  Black-capped Chickadees will love you.  Mealworms mimic WORMS.