QBARS - v27n2 An Early Report on Freeze Damage

An Early Report on Freeze Damage
Harold Greer, Eugene, Ore.

The winter of '72' will be a year long remembered but is also a year that all would like to forget. 'Old Man Winter' went on a rampage this year. From out of Siberia came a cold blast that was not stopped by the normal weather patterns from the Pacific. After a warm fall, temperatures fell from the 60's to -12° F in a matter of days causing damage that would not have otherwise occurred. The official low recorded at the Eugene Airport was -12° F, however the temperatures in the area varied from about -4° F to -20 ° F.
About three to four inches of snow fell in the area. This was very powdery snow which did not stay long on the larger plants. There was also sun during the 10-day period in which the temperature never went above freezing.
While it is too early to assess the damage completely it appears that about 75% of the plants in the area received some damage, varying from slight leaf burn to complete defoliation and death. Virtually all of the Rhododendron buds are damaged with only some of the H-1's surviving. Most of the fruit and nut orchards in the area are damaged with many completely destroyed. Walnuts and peaches were hurt the most.
Dr. Carl Phetteplace, who has a most outstanding Rhododendron collection. lost many of the plants he has spent his lifetime collecting. His 35 year-old R. barbatum , a 15 foot 'Sir Charles Lemon', a 10 foot R. falconeri and his fine Rock collection are all dead. All the 'Loderis', arboreums and their hybrids, the Grande and Falconeri series, and most of the Triflorum Series, to name a few, are dead. Almost all of the evergreen azaleas and camellias were also killed.
The amount of damage done by the cold of course varied with exposure.  Plants rated H-1 and H-2 that were exposed to the sun were damaged while some H-4's in more protected areas survived. While the full effects of the freeze will not be known until later, it is a sure cinch that '72 will go down in our memories along with '49, '55 and the rest of those years we would like to forget.