Weather Extremes in the Ohio Area
Gordon G. Emerson, Rock Creek, Ohio
Fig. 27. Winter damage to strongly
built lath house, Ohio
The accompanying photograph indicates the beating many lath houses in Northeastern Ohio took from ice and near-record snow accumulations last winter. What happened to rhododendrons and azaleas, particularly those with brittle branches, is probably better left to the imagination.
The onslaught of weather began the second week of December with six to eight inches of heavy, wet snow which weighed shrubs and even trees to the ground. Before most homeowners had a chance to clear the accumulations away, the snow froze. Then came a series of blizzards which piled up foot on foot of the white stuff. More than 80 inches was officially measured at Cleveland and some less favored areas had even more.
Five Cold Waves
During the next 3½ months five major cold fronts rolled down from Canada, plunging temperatures to an all-time record low of minus 19 at Cleveland Hopkins Airport. A half hour's drive inland there were semiofficial readings of minus 28 degrees the same night, and readings of minus 20, or lower, on four other occasions. Fierce winds accompanied several of the fronts, bringing wind chill readings in the minus 30-35 degree range-sufficient to kill flower buds of R. mucronulatum in many plantings.
The sight greeting homeowners and nurserymen when the snows began to retreat in mid-March was enough to discourage all but the most avid fanciers of broadleaf evergreens. At the spring meeting of the Great Lakes Chapter David Leach described the scene at Brookville, Pa., as "a sea of brown." Virtually everything which was exposed to the wind for any length of time was damaged, the very few exceptions, being mainly among the older R. catawbiense hybrids.
Rainfall during April was relatively light, temperatures were moderate, and many plants which seemed lost began to show signs of recovery. But the first week of May another cold front moved out of the Arctic. Temperatures dipped to near freezing, then freezing-ruining the swelling floral buds of early-flowering azaleas and rhododendrons as well as cutting short the season for spring bulbs and perennials.
Warm Weather-Late Freeze
As soon as the damage was done temperatures again warmed. New growth began to break from auxiliary buds and branches of damaged plants. Floral buds swelled, the mid-season varieties bloomed, new growth expanded; and where there had been fears a month or six weeks earlier that there would be no flowers for the Chapter show at Pittsburgh, there were now indications of a surplus.
Mother Nature was not finished, however. The night before the - show luckily after most trusses and plants were safely indoors - another cold blast hit, bringing temperatures down to the mid-20s and coating everything with about the heaviest frost that will ever be seen in this area. Even in some "favored sections" along the Lake Erie shore there were readings below freezing. New growth, not only of rhododendrons, but of taxus, spruce and a host of other ornamentals was cut back to hard wood.
Many Factors Involved
To evaluate the overall damage to nursery stock and home plantings will require much time, perhaps several years. Because of the complex of factors involved a survey aimed at adding to the knowledge of the hardiness of individual varieties would be less valuable now than some taken after severe winters of past years.
Was the failure of a particular variety due to extreme temperatures, breakage, rodent damage, the late frosts, or a combination of these factors? Was the good show of another variety due to its low-growing habit and insulation from the cold? Was it due to protection from wind chill?
In one nursery plants of 'Cunningham's White' and 'Boule de Neige' each had the same amount of snow cover. Flower buds of the first suffered only moderate damage while those of the much hardier-rated 'Boule de Neige' were practically all killed. At another location a five-foot 'Cynthia' opened every bud while a few feet away 'America' and 'Charles Bagley' were damaged. At the same site ground-hugging layers of 'Goldsworth Yellow' and R. vernicosum opened every bud without the slightest evidence of damage to the flowers. But the 'Goldsworth Yellow' was literally shattered by the weight of ice and snow and is unlikely to see another season. Nearby, a larger plant of the much hardier 'Mars' opened most of its blossoms but suffered extensive bark damage. The last frost cut back the new growth of 'Mars' and finished the wilting and yellowing foliage of 'Goldsworth Yellow' while the R. vernicosum (bark, buds and new growth) came out of it all unscathed. All were buried under a four-foot drift of snow during the worst of the cold.