The researchers studied how the root respiration of Fraxinus mandushurica in a forest in Changbai mountains changes throughout the seasons. They measured the root respiration rate from May to October 2007 and found that it varied with the highest rate in July and the lowest in October. The root respiration rate increased with higher air and soil temperatures, as well as with more nitrogen in the roots. However, too much water in the soil decreased the root respiration rate. The response to temperature varied with the age of the trees, with older trees showing a greater increase in respiration rate with temperature.