Merle Haggard is in a California hospital for treatment of a recurring bout of double pneumonia.

A statement from his publicist on Tuesday said Haggard has had to postpone his concert dates in March.  According to the statement, the 78-year-old musician also cancelled dates last month as he was still suffering from his last bout of pneumonia in both lungs.   Haggard has been told by doctors to rest and recover for at least one more month without performing.

The 78-year-old singer had also cancelled some dates in February because he was still feeling weak from a previous case of pneumonia in both lungs, but then returned to the stage last month.