Cold-Damage from Leaving Fruit on Trees During a Freeze

Last fall the Owari satsuma trees at J.L. Lomax produced a tremendous amount of soft fruit that became puffy very quickly. Category 2 hurricane Helene may have contributed to the fruit quality being so bad last year. With all the fruit soft and of low quality we only harvested fruit from 12 of the 60 trees. The 12 trees harvested were part of a pruning trial.  With the 48 remaining trees being fully loaded with fruit I was concerned that some of the trees may not make it through the winter if we experienced really cold temperatures.  Although it did snow in January, it didn’t get as cold as it did at the end of 2022. The 12 trees with all the fruit harvested definitely look healthier and thicker than most of the other trees and have a darker color.  I have also observed dead limbs (Fig. 1 & 2) on many of the trees so I decided to do a quick, “non-scientific”, evaluation to see which trees had obvious dead limbs. I basically walked slowly past the trees and recorded whether or not I saw dead limbs on each tree as I went by.  I observed both sides of each tree so each tree received two ratings of either “yes” or “no”.  A tree could have a “yes” on one side and “no” on the other.  Of the 12 trees we harvested appropriately, only one side of one tree had dead limbs. Therefore, of the 24 sides observed, 23 did not have noticeable dead limbs. For the remaining 48 trees I observed both sides which totaled 96 sides observed.  Of the 96 sides, 77 had noticeable dead limbs. To sum it up, only 4% of harvested trees had dead limbs compared to 80% with dead limbs on trees where the fruit was left. This is more reason to harvest all the fruit from your trees as quickly as possible. These “Owari” satsumas were on 10 different rootstocks with 6 repetitions of each tree. Below are the ratings (Table 1), from each rootstock. Trees on X-639 and US-812 were harvested in November and in red. The rest were not harvested. 

Figure 1: Tree sides showing limb dieback.