Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of irrigation systems maker Lindsay (NYSE: LNN) jumped as much as 12.1% above last night's closing price on triple the average trading volume.

So what: Lindsay didn't do much to deserve this pop, other than be a close competitor to Valmont Industries (NYSE: VMI), whose fourth-quarter report blew past analyst estimates. Moreover, a huge short interest in Lindsay's stock amplifies any positive move as panicked shorters start closing out their positions.

Now what: Lindsay's own earnings report is over a month away and the afterglow of Valmont's report will have faded by then. When it rolls around, you should compare Lindsay's sales and earnings performance to 62% revenue growth and 150% higher irrigation-related profits for Valmont. The company does occasionally post a quarter like that, but the last one fell in the summer of 2008. This looks like an adrenaline-fueled overreaction.

Interested in more info on Lindsay? Add it to your watchlist.

Fool contributor Anders Bylund holds no position in any of the companies discussed here. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool is investors writing for investors.