Deal$ stores offer general merchandise at deep discounts, but the prices are not strictly $1, like Dollar Tree units. Dollar Tree will keep the Deal$ name on the stores and might look at integrating different price points into its flagship chain, said Bob Sasser, Dollar Tree's president and chief executive officer, during a conference call with analysts.

"We'd like to explore some other ways of retailing," he says, explaining that some Dollar Tree customers could be shopping elsewhere for large plastics items, like trash cans, that can't be sold for $1. But Sasser stresses that changing the merchandise in Dollar Trees is "way out there in the horizon right now."

Sasser says he expects the deal to close by the end of March. The $30.5-million acquisition price could increase depending on the amount of inventory his company buys from Minneapolis-based Supervalu.