Every quarter, many money managers have to disclose what they've bought and sold. Their latest moves can shine a bright light on smart stock picks.

Today let's look at Columbia Wanger Asset Management, which sported an overall portfolio valued at $23.1 billion as of March 31, 2012. Founded in 1992, it's now a subsidiary of Ameriprise Financial and manages mutual funds and favors small-cap and mid-cap companies.

Among Columbia Wanger's top five holdings you'll find names including lululemon athletica, Ametek, and Donaldson.

Interesting developments
So what does Columbia Wanger's latest quarterly 13F filing tell us? Here are a few interesting details:

New holdings include LED lighting specialist Cree (Nasdaq: CREE), which has struggled recently, but is poised to do well as business picks up, in part due to its investments in expanding its capacity, and also from its new products, such as cheaper and more efficient lights. Its competitive position is strong, but some are worried about the recent news that its CFO is departing. That doesn't necessarily mean much, though. Executives do change companies now and then.

Among holdings in which Columbia Wanger increased its stake was Florida real estate enterprise St. Joe (NYSE: JOE). It also got a new CFO recently, and one who has been associated with some big corporate changes at other companies he's worked at, suggesting to some speculators that perhaps St. Joe is setting itself up to be sold. It's long been a controversial company, with Greenlight Capital's David Einhorn hating it and Fairholme's Bruce Berkowitz loving it.

Columbia Wanger reduced its stake in lots of companies, including Kodiak Oil & Gas (NYSE: KOG). Kodiak has seen its revenue explode lately, more than tripling over the past year. It's a major player in the promising Bakken shale fields, and has recently turned the corner into profitability. The biggest issue with the company seems to be whether its stock is overvalued.

Finally, Columbia Wanger unloaded several companies, such as Diamond Foods (Nasdaq: DMND) and Northern Oil and Gas (NYSE: NOG). Diamond Foods is another company with management turnover, but in a more serious vein, ousting its CEO and CFO after alleged improper payments to suppliers. Oaktree Capital Management recently took a stake in the company, infusing it with $225 million to bolster its balance sheet.

Northern Oil and Gas also operates in the Bakken fields, with some seeing it as an intriguing investing opportunity. It has been posting huge growth numbers for both revenue and earnings recently.

We should never blindly copy any investor's moves, no matter how talented the investor. But it can be useful to keep an eye on what smart folks are doing, and 13F forms can be great places to find intriguing candidates for our portfolios.

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Longtime Fool contributor Selena Maranjian, whom you can follow on Twitter, holds no position in any company mentioned. Click here to see her holdings and a short bio. The Motley Fool owns shares of lululemon athletica. Motley Fool newsletter services have recommended buying shares of lululemon athletica. The Motley Fool has a disclosure policy.

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