I've been trying to grow Yellow Pears for the last several years and they have been failing midseason. Two days ago they were alive and well and this afternoon they had dying branches and one stem of small tomatoes had wilted as though it had been deprived of water. We've had plenty of rain, and I don't know the cause of the problem. My Red Pear appears to have the same issue, though my other 14 plants (1 each of various heirloom varieties) appear to be unaffected. Any advice? Thanks!