ATLANTA, March 30 (Reuters) - The chief executive of home improvement retailer Lowe's Cos. (nyse: LOW - news - people) said on Tuesday that he does not expect plywood prices, which are up more than 100 percent in the past year, to decrease. "I don't think you'll see plywood prices come back down," Robert Tillman told a New York consumer conference in remarks carried over the Internet. "The supply is now pretty well managed. There's not an oversupply. There are fewer manufacturers." Tillman said prices of other wood may fluctuate. Lumber prices, specifically plywood and other structural panels used in...