TVGuide.com said Ron's mother will be introduced early in Season 4, which kicks off next month on NBC.
Series executive producer Mike Schur told the Web site Pell is "no shrinking violet" and a character breakdown of the role describes her as "a no-nonsense, patriotic, salt-of-the-earth farm woman," TVGuide.com said.
Pell is longtime writer for "Saturday Night Live," the sketch comedy show on which "Parks" lead actress Amy Poehler started her career.
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