X0202 4 2006-04-10 0 0000075129 OTTER TAIL CORP OTTR 0001191500 SPIES GARY J 215 S CASCADE ST FERGUS FALLS MN 56537-2801 1 0 0 0 Common Stock 2006-04-10 4 A 0 2200 28.235 A 4100 D Shares of Common Stock acquired under the Corporation's Stock Incentive Plan, which is a grant of Restricted Stock. The 2,200 shares granted 4/10/06 have a grant price of $28.235 and vest at 25% yearly beginning 4/8/07. See below for other holdings: 1. Direct holding of 1,040 shares with 1,000 shares of this total held in "street name" with Piper Jaffray. 2. Direct holding of 968.9333 shares held in the Dividend Reinvestment Plan. 3. Direct holding of 2,900 shares which no longer carries the restriction. 4. 8,644.2470 common stock units with no specific expiration date. 5. 2,000 stock options with expiration date of 4/8/2011. /s/ Gary J Spies by Debra J Lill -POA 2006-04-12