Ugg sales stay strong -- How about Deckers?

I've seen too many high-flying fashion stocks crater back to earth to take bullishness with companies like Deckers Outdoor (NASDAQ: DECK), the maker of Uggs, too seriously. Remember L.A. Gear?

But Deckers has had an amazing run this year, hitting a new 52-week high on Friday, making it a solid triple for the year.

According to Fortune, "Now, analysts are predicting even more upside for Deckers' stock. The reason? While other brands have been heavily discounted this holiday season, Ugg boots, which can cost upward of $200 a pair, are selling at full-price in most major department and specialty stores. More full-price sales mean fatter profits for the all-important fourth quarter."

It's all very exciting but I think investors need to be very careful. Uggs account for nearly 90% of Deckers' revenue, far outshining their Simple and Teva brands.

A bet on Deckers is a bet on the continued success of a pretty bizarre fashion trend -- at 50 times earnings and more than 5 times sales.

It's easy to be bullish when everything is going well, but traders will be dumping this one like they dumped Crocs (NASDAQ: CROX) at the first sign of slowing growth. And at some point, won't people have all the Uggs they need?

With about 19% of the float short, it looks like more than a few investors are lining up to bet signs of weakness are near.