The former Burnley and West Ham ace underwent groin surgery at the end of last season but has been troubled by groin and hip pain throughout pre-season.
"Junior Stanislas is out and that's a big miss at the moment," said Howe.
"I don't see it being particularly long, a month maximum."
Howe revealed that both Jermain Defoe and Steve Cook will be in contention for the opening day clash against West Bromwich Albion at the Hawthorns
"Everyone else is in contention for Saturday," added the Cherries boss.
"We've got a good squad this season and in my seat, you don't want to disappoint people.
"It does give you some confidence though that we have a number of good players and over the season, everyone will have to play their part."