I have a pear tree that last season was loaded with pears. This season it flowered as usual. I have only 3 pears on it. I lost its pollinating partner last Summer,,though there are other pear trees in my area. The flowers that did not turn into pears are black. At the time of flowering we had a very cold night. Down to 20'! I also have fireblight in my area though this tree shows no signs of it. Did I lose tis years crop to lack of pollination? A freezing night. Or fireblight? Alotto ask I know. thanks