 -- In the wake of the passing of country legend Merle Haggard, the Country Music Hall of Fame and Museum ordered flowers and a condolence book for fans to sign, placing both next to his bronze likeness in the Hall’s rotunda.

Meanwhile, the biggest stars in country music took to social media to remember the country music legend.

"We've lost one of the greatest writers and singers of all time," Dolly Parton said in a statement obtained by ABC News. "His heart was as tender as his love ballads. I loved him like a brother. Rest easy, Merle."

Added Clint Black on Twitter, "We've lost a giant. No words for what @merlehaggard's music meant to me. I know his mind is now untangled forever."

Haggard died Wednesday, on his 79th birthday, his son Ben confirmed on Facebook.

"A week ago dad told us he was gonna pass on his birthday, and he wasn't wrong. A hour ago he took his last breath surrounded by family and friends," he wrote. "He loved everything about life and he loved that everyone of you gave him a chance with his music. He wasn't just a country singer.. He was the best country singer that ever lived."

His colleagues agreed. Their sentiments are below: