Welcome back to another Foolish review of the coldest stocks, as ranked by Motley Fool CAPS. We're looking at the three worst-performing industries over the past 30 days, and your favorite short and long candidates in each.

For the fifth straight week, ethanol producers are sliding like California's infamous San Andreas Fault during an earthquake. Stocks in this sector are down 13.1% over the last 30 days.

Who are the others? Have a look:

  • Second worst, for the second straight week, are the optical components makers. Riding the light has brought forth dark times for stocks like Oplink Communications. As a group, they're down by 12.8% over the past 30 days.

  • Third worst are the fab-less semiconductor makers. Less than fabulous lately, stocks of chip chumps like Vimicro (NASDAQ:VIMC) are, as a group, down 10.6% over the past 30 days.

According to you, our Foolish readers, the worst stocks in these industries to own now --i.e., those rated one or two out of a maximum five stars in CAPS -- are:

Company

CAPS stars
(5 max)

No. of CAPS ratings

Bearish CAPS ratings

Bear ratio

U.S. BioEnergy (NASDAQ:USBE)

*

107

80

74.8%

Verasun Energy

*

188

115

61.2%

Aventine Energy

*

124

66

53.2%

Bookham

*

40

16

40.0%

Pacific Ethanol

*

366

139

37.9%

JDS Uniphase

*

369

90

24.4%

Source: Motley Fool CAPS

And your favorite long candidates -- i.e., those rated four or five stars in CAPS -- are:

Company

CAPS stars

No. of CAPS ratings

Bullish CAPS ratings

Bull ratio

Actions Semiconductor

****

193

191

98.9%

Marvell Technology (NASDAQ:MRVL)

****

702

667

95.0%

Finisar

****

196

184

93.9%

Source: Motley Fool CAPS

Do you agree? Disagree? Let us know what you think by signing up for CAPS today. It's 100% free to participate.

Cap off your day with related CAPS Foolishness:

Fool contributor Tim Beyers, ranked 1,494 out of more than 22,700 in CAPS, is a sucker for growth stocks and a regular contributor to David Gardner's Motley Fool Rule Breakers service. Tim didn't own shares of any of the companies mentioned in this story at the time of publication. The Motley Fool's disclosure policy freezes out Wall Street's worst.