In the same way, estimates of likely frost damage based on data obtained from meteorological stations can be misleading. Again taking the example of pre-Andean valleys of Argentina, suitable thermal regimes for reproductive development are found around the periphery of high mountain valleys but with danger of frost where cold air drains through the orchards to the valley floor below. Small differences of elevation around this periphery result in large differences in minimum temperature and duration. On some winter days, minimum temperature at the same altitude can very from -5 to -10 for durations of 4-10 h. within a distance of several km due to slope. The solution is to avoid valley locations where cold air accumulates and locate orchards higher in the foothills. Here, row orientation can also play an important role by ensuring that the cold air is not trapped in orchards (Section 4.2)