AmericanaramA, which began June 26 and runs through August 4, is effectively Bob Dylan's baby -- a package tour, headlined by Dylan and supported by Wilco, My Morning Jacket and a few different opening acts. (The final leg of the tour, which starts Thursday, will feature Ryan Bingham as an opener; on July 27, in Wantagh, NY, Beck will appear in lieu of MMJ.) The show-opening performers of the first two segments of the tour, though, have been artists with careers almost as long as Dylan's, who've been playing his songs for decades. And the tour's been marked, so far, by a string of collaborations and cross-tributes.

A few days before AmericanaramA even started, Wilco hinted at things to come: on June 21, they played an all-covers set at the Solid Sound Festival in Massachusetts, which featured their take on Dylan's "Simple Twist of Fate."

The Grateful Dead's guitarist Bob Weir opened the first handful of shows on the tour. His six-or-seven-song sets included a bunch of Dead-era songs, as well as his interpretations of songs by Delbert McClinton, Little Feat and the Platters. And he dove into the headliner's songbook, too, covering Dylan's "Most of the Time" and "When I Paint My Masterpiece." The latter was part of the Dead's repertoire for some years: here's a clip of them playing it in 1987.

The intergenerational collaborations started happening right away, though. On the first night of the tour, Weir sat in with Wilco for the Dead's "Ripple" and Wilco's own California Stars." That same night, he played the Beatles' "Dear Prudence" in his opening set; the next night, My Morning Jacket included "Dear Prudence" in their part of the program, and brought Weir in to play it with them.

That grew into Weir turning up all over Wilco and MMJ's sets for the next few days. He played the Dead-associated songs "I Know You Rider" and "Brown-Eyed Women" with My Morning Jacket, and got in on the Beatles stakes by playing "Tomorrow Never Knows" with Wilco (below). The conceptual coup of the tour's early dates, though, was probably the medley of the Dead's "Dark Star" and Wilco's "California Stars."

The great British singer/guitarist Richard Thompson and his trio joined AmericanaramA at the beginning of July, although he's very specifically not an American artist. (A famous Thompson anecdote: in response to a demand for "rock 'n' roll!" from an audience member at an early show by his band Fairport Convention, he replied "This is rock 'n' roll. English rock 'n' roll.") He's been playing the same five-song opening set every night, but reappearing in the guest spot in Wilco's set -- most often with "Sloth," the long, harrowing jam that became the centerpiece of Fairport Convention's live shows for many years. Here's a marvelous 1970 clip of Fairport playing it.

Thompson's had a longstanding affinity for Dylan's songs, too, though he hasn't played any so far on this tour. Fairport Convention's one and only British chart single was a Dylan cover -- a Cajun-style version of "If You Gotta Go, Go Now," sung in French as "Si Tu Dois Partir," in 1969.

In Duluth, Minnesota, last week, Wilco and Thompson added even more musicians to the stage: locals Low, who joined them for a take on Gordon Lightfoot's 1976 hit "Wreck of the Edmund Fitzgerald." (If Lightfoot is only known to you through that light-rock warhorse, it's worth noting that in the '60s he was generally considered in the top rank of new-generation singer-songwriters: both Dylan and the Grateful Dead covered his "Early Morning Rain," and Nico's first single was a version of his song "I'm Not Sayin'.)

Dylan's generally been staying out of the all-star team-ups so far on this tour -- he's been playing oddly predictable sets, by his standards. On July 14, though, he nodded to his opening act by covering one of Richard Thompson's greatest songs, "1952 Vincent Black Lightning." (Here's a gorgeous solo acoustic version by Thompson from a few years ago.)

And maybe the most touching moment of the tour so far has been another cover by Dylan: on July 10, in St. Paul, Dylan played Bobby Vee's first hit, "Suzie Baby." Vee, who was diagnosed with Alzheimer's disease two years ago, was in the audience; more than fifty years ago, in the summer of 1959, Dylan had briefly toured as a piano player in Vee's band. "We had the same history and came from the same place at the same point in time," Dylan wrote in Chronicles. "Every time I'd see his name somewhere, it was like he was in the room."