The study looked at how to predict when pear, apple, and plum trees would flower. They used weather data and observations of other plants to make their predictions. They found that the date of full flowering is closely linked to when birch trees start growing leaves. For apple and plum trees, the temperature in March and April is important, while for pear trees, it's the temperature in February and March. They also discovered that they could predict pear tree flowering 22 days in advance, but only 2 days for apple trees. Surprisingly, the amount of rain didn't affect when the trees flowered.