It’s the 50th anniversary of “Hair: The American Tribal Love-Rock Musical.”

“Hair” was post-hairspray. Young women let Aqua Net on the shelf, ironed their hair, or went Afro. Young men let Brylcreem on the shelf and skipped the barber.

“Hair” was pre-”Hairspray.” It set the stage for other non-book Broadway musicals (“Company,” “Godspell,” “Pippin”).

“Hair” is of a time, a time that now seems long ago, naive and quaint. It not only seems long ago. It was long ago: a half-century long ago.

The Muhlenberg Summer Music Theatre (MSMT) production of “Hair,” through July 2, John C. Empie Theatre, Dexter F. and Dorothy H. Baker Center for the Arts, Muhlenberg College, Allentown, captures the spirit of that time.

MSMT’s large, young cast of 24, directed with reverence, understanding and sensitivity by James Peck, is exuberant, sounds excellent in ensemble singing, with music direction by Ed Bara, backed by a nine-piece orchestra conducted by Vince Di Mura, and is energetic in the nearly-nonstop choreography by Samuel Antonio Reyes that blends the frug, the pony, the swim, shag, and go-go. The June 14 opening night “Hair” performance was reviewed.

Costume Designer Lex Gurst outfits the actors in hippie attire, including head bands, beads, dashiki and paisley tops, vests, sandals, boots and bell bottoms.

Scenic Designer John Raley utilizes a four-level scaffold festooned with elements of an American Flag, and the Statue of Liberty, except the crown, torch and head are disconnected, much like the era. Lighting Designer Curtis Dretsch brings psychedelic colors and even some strobe lights to illuminate the scenes and, in Act One’s closing brief nudity, to keep things in the dark.

Bree Ogaldez (Ronny), lead vocalist, and the “Tribe” (the ensemble) is astounding in the opening, well-known “Aquarius,” which heralds “the dawning of the Age of Aquarius.” The lyrics in this and other songs (Gerome Ragni, James Rado, lyrics; Galt MacDermot, music) set the tone for the musical, as well as representing the tenor of the times and aspirations of many in the mid- to late-1960s, hitting all the right tropes: “Golden living dreams of visions ... Mystic crystal revelation ... the mind’s true liberation ... peace ... love.“

At the center of what little story there is in “Hair” (Gerome Ragni, James Rado, book) is Alan Mendez (Claude), who, along with Gabe Martinez (Berger) and the cast, sings the emblematic title song, “Hair,’” with hair-waving, hip-shaking and arm-raising abandon.

Claude, as with eligible young men of the era, faced the military draft (Selective Training and Service Act, 1940 - 1973, when the U.S. Armed Forces went to an all-volunteer military force), and that meant possible overseas duty in the Vietnam War (1955-1975), the object of protests, civil disobedience and campus unrest in the United States. “Hair” confronts this in the “Be-In-Hare Krishna” scene depicting the burning of draft cards and hallucinogenic impressions of Vietnam War battles (including hovering helicopters in the sound design by Phil Ingle).

“Hair” is an amalgam of pop, folk-rock songs (some 24 in the first act and 14 in the second act, many mostly snippets). Among the memorable, in addition to the aforesaid, are others that, in recordings (The Fifth Dimension, Cowsills, Three Dog Night, Oliver) topped Billboard charts. Cameron Silliman (Sheila) makes “Easy To Be Hard,” her own, with an expressive, heart-rending rendition.

Drew Maidment (Margaret Mead) proves comic relief with the hilarious “My Conviction.” Amanda Foote (Jeanie), Felice Amsellem (Dionne) and Emily Spadaford (Crissy) vocalize splendidly in “Air.” Asia DeShields, Gabrielle Hines and Ogaldez are show-stoppers as The Supremes Trio in “White Boys.” Ogaldez, Ashley Heister (Leata) and Mendez are moving in “What A Piece Of Work Is Man” (inspired by Shakespeare’s “Hamlet,” Act 2, Scene 2).

Silliman and the ensemble head the show toward a big close with “Good Morning Starshine.” Mendez, Silliman, Amsellem and the Tribe ensemble present a rousing conclusion with “Let The Sun Shine In.”

One of the ironies of “Hair” is that the song, “Manchester, England,” weaves in and out of the production (there’s also “Manchester II” and “Manchester III”). It’s sung by Mendez and the tribe as a longing for a kind of reverse British Invasion music and cultural connection. “Manchester” has taken on a whole other connotation. So has “Hair.”

Tickets: Muhlenberg College box office, Trexler Pavilion for Theater and Dance, 2400 Chew St., Allentown; muhlenberg.edu/SMT; 484-664-3333.