Bird seed types, and who actually eats them

A bag of bird seed is a mixture of things with wildly different value to a bird. Learning eight names is enough to read any panel in the shop and know within ten seconds whether it is worth buying.

The seeds worth buying

Black oil sunflower

The default. A thin shell most birds can crack, high oil content, and the broadest appeal of any single seed — Project FeederWatch names cardinals, chickadees, finches and sparrows as favoring it. Wagner's publishes 14% protein and 24% fat for its single-ingredient bag.

Eaten by: almost everything at a feeder. Downside: hulls under the feeder.

Striped sunflower

Bigger, with a thicker shell. Cardinals, jays and grosbeaks manage it; small birds struggle. Sometimes recommended as a way to exclude house sparrows and starlings, which it partly does — along with anything else with a small bill.

Safflower

A small white seed with a hard shell. Cardinals, house finches, chickadees and titmice eat it; most squirrels and many grackles do not. Wagner's publishes 17% protein and 25% fat. The squirrel effect is a tendency, not a rule — the honest version is here.

Nyjer (thistle)

Tiny, black, oil-rich, imported, and expensive. Project FeederWatch credits it with attracting American Goldfinch, Pine Siskin and Common Redpoll. It needs a narrow-port feeder or it pours straight onto the ground, and it goes stale faster than anything else on this page. Buy small bags: detail here.

Peanuts

Shelled or in-shell, and the fastest way to bring in woodpeckers, jays, titmice and nuthatches. Also the most squirrel-attractive thing you can hang up, so they need a mesh feeder and preferably a mechanism. See peanut feeders. Keep them dry — damp peanuts spoil and can grow mold, which is genuinely dangerous.

Suet

Not a seed, but it belongs in this list because it is the other thing your feeder station should carry from October. Rendered fat, often with seed, nuts or mealworms in it. Highest energy per gram of anything you can offer. See suet and suet cakes.

The three fillers

Milo (sorghum). Round and reddish-brown. Project FeederWatch says plainly that it is “not a favorite of most birds, and the seed often goes to waste,” and that in the east it is best to avoid mixes with large amounts of it. It is cheap and it adds weight, which is exactly why it is in the bag.

Red millet. White proso millet is genuinely eaten by ground-feeding birds — juncos, doves and sparrows. Red millet is the cheaper relative and mostly gets left.

Cracked corn. Eaten by doves, jays and ground feeders, so it is not useless — but in a hanging feeder it mostly gets flicked out, and it absorbs damp faster than anything else in the bag, which is how a feeder starts growing mold.

Reading a bag in ten seconds

1. Turn it over.
2. Read the first three ingredients.
3. If any of milo, red millet or cracked corn appears there, put it down.
4. Check the fat percentage. Under about 20% means you are buying a lot of filler.

Seed decides which feeder you need