Composer Bob Nolan, 72, who wrote the Western song classics "Tumbling Tumbleweeds" and "Cool Water" and sang with the Sons of the Pioneers, died Monday following an apparent heart attack.

He became ill on his way home from a boat outing with a son and daughter and died before reaching a hospital, a family spokesman said.

Mr. Nolan -- with Tim Spencer and a young cowboy singer named Leonard Slye, who later changed his name to Roy Rogers - formed the Pioneer Trio in the early 1930s. The group, with the addition of Lloyd Perryman and the Farr brothers, Hugh and Karl, became the Sons of the Pioneers in 1934 and dominated Western music in the 1930s and 1940s.

Rogers left the Sons of the Pioneers in 1947 to work in movies and Mr. Nolan's quavering baritone became the group's primary sound.

Called by some the the foremost Western songwriter of his time, Mr. Nolan wrote about 1,000 Western, gospel, and country and Western songs. "Bob was way ahead of his time as a songwriter," Rogers said. "He started a whole lot of people writing Western music."

Mr. Nolan and the Sons of the pioneers appeared with Rogers in 150 Western movies and Rogers "screamed like a smashed cat" if told the group would not be able to perform in any particular film, he said.

Mr. Nolan was born in New Brunswick, Canada, but moved to Arizona with his family as a child and was a drifter through the West as a young man.

Survivors include his wife, Clara, of Newport Beach, Calif., where the couple lived, two sons and a daughter.