More frequent freeze-thaw cycles in winter can increase biomass production according to the results of a recent study. Researchers installed underground heating on their plots, thereby enabling five additional thawing periods to take place in the winter of 2005/2006. They found that on the manipulated plots ten percent more biomass grew compared to on the control plots. Such increased plant productivity can be explained by several factors; such as an increase in nitrogen supply in the spring, according to the researchers.