Southwest Airlines will stop giving away peanuts on flights next month, ending a decades-long tradition.

The airline said Tuesday it was pulling peanuts from all flights because of concern for passengers with peanut allergies. They will be replaced by pretzels and, on some longer flights, other free snacks. Southwest said the decision follows months of deliberation and isn’t tied to any particular incident involving passengers with allergies.

No snack is more closely identified with a U.S. airline. Over the years, Southwest used the humble legume in marketing campaigns. A blog on its website is called Nuts About Southwest.

Some of Southwest’s other early quirks, like dressing flight attendants in hot pants, went out decades ago, but the peanuts survived. Until now.