Pamela J. Bennett
Jane C. Martin
The spring of 1997 unfolded slowly and was followed by a cooler than normal summer. Record lows on April 9 and 10 were reported from many parts of the state, followed by an abnormally cool May; there were reports of plants and insects emerging later than normal. April was dry across Ohio, with below normal rainfall. May and June rainfall was above normal, July was slightly below normal, and August was above normal. Rainfall as of September 23 was below normal.
A few species of plants exhibited winter injury while a number of plants experienced various damage due to low temperatures and scattered frosts in April. Dry periods during the summer resulted in several species exhibiting yellowing of foliage and leaf scorch. Reports continued into the fall regarding plants blooming later than normal and insects extending their activity.
Included in this report is a compilation of Ohio weather conditions and noteworthy environmentally induced and cultural plant problems in 1997. Observations are drawn from information provided in Ohio State University Extension's Buckeye Yard and Garden Line and the Ohio Department of Natural Resources Monthly Water Inventory Report and information from the State Climatologist's Office for Ohio.
The most significant early season weather event was severe March flooding in southern Ohio and northern Kentucky. Following this, the spring of 1997 developed slowly in Ohio. Temperatures averaged well below normal in April. Cincinnati and Columbus reported 22 days of below normal temperatures, and Cleveland reported an average of 3 degrees F below normal. Record lows were set on April 9 and 10, with temperatures dipping as low as 15 degrees F in some areas. Rainfall was noticeably below normal across the state in April. The state average was 1.65", which was 1.86" below normal. This ranked as the ninth driest April in the last 115 years. Most precipitation fell as light rain showers.
May remained cool. Cleveland reported the second coolest May on record, with the average high temperature being 52.2 degrees F. Cincinnati reported the third coolest May on record, with an average high of 57 degrees F; Columbus had an average high of 56.5 degrees F. Rainfall was above normal across most of the state. The average was 5.31", 1.56" above normal. It was the second wettest May in 106 years in the northwest and north-central regions of Ohio. Heavy rain fell on May 1-2 and was much needed after a dry April. May 18-19 brought heavy storms, some with localized flash flooding in southern Ohio. Heavy storms arrived again on May 24 and 25 followed by a slow moving storm on May 29-June 2, which triggered some additional flooding.
Temperatures were below normal the first half of June, but warmed to near normal in the second half. Rainfall was above normal across most of Ohio, with a state average of 4.99", 1.03" above normal. Strong storms on June 16-18 were common statewide. The last 10 days of the month were dry.
Other than a cool period ranging from seven to 10 days around the Fourth of July weekend, July temperatures were normal or slightly above normal. Rainfall was slightly below normal with a state average of 3.34", which was .58" below normal. A few locations in southwestern Ohio and numerous locations in northeastern Ohio reported less than one inch of rain in July. Rain fell as showers and thundershowers with some locally heavy storms. Most rain fell in the first and last 10 days of the month with the middle rather dry in most locations. On July 26 and 27, 8" of rain fell in east-central Ohio, which caused severe flooding that closed I-70 for two days.
August cooled off with below normal temperatures; Cincinnati reported 18 days of below normal temperatures, and Columbus reported 15 days. Record lows were set the first week with Cleveland reporting 48 degrees F, Mansfield reporting 49 degrees F, and Youngstown reporting 41 degrees F. August rain fell as showers typical of the season, and rainfall was above normal in most of the state, with a few locations in southern and western Ohio with below normal rainfall. The state average was 4.86", 1.38" above normal. Most rain fell in the middle of the month.
September was also cool and dry. Cincinnati reported 16 days and Columbus reported 12 days with below normal average temperatures. A low of 44 degrees F was set on September 4 and 5 in Columbus and Cincinnati, respectively. Rainfall was also below normal for the month, with only .55" reported in Cincinnati and 1.36" reported in Columbus.
Little winter injury to plants was reported with the exception of the following - stem splitting on rhododendron, leaf browning from winter desiccation on boxwood, and cane damage to roses.
Record low temperatures in early April resulted in leaf burn damage to Callery pears, crabapples, wintercreeper euonymus, red-leaved Japanese maples, ajuga, and katsuratree. Frost damage was noted on the primary buds of red oak and silver maple in central Ohio, and bur oak and green ash in southern Ohio. Perennials such as hosta and bleeding heart suffered foliage damage as a result of these frosts. It was observed that the farther south one went in Ohio, more damage was apparent. This was because plants were further along in development.
Cool spring weather conditions resulted in many plants experiencing delayed blooming or prolonged blooming. While the first blooms of roses were delayed, daffodil, serviceberry, and crabapples enjoyed a very long season in the spring. By mid-summer, plants were still noted to be about 10 days behind their normal blooming period. Plants such as daylilies, rudbeckia, anemones, hydrangea, and many ornamental grasses were delayed up to two weeks from their normal bloom times.
Hot, dry conditions in late June and July resulted in leaf yellowing of birch and tuliptree, and leaf scorch on red oak, horsechestnuts, and buckeyes. Dry summer weather also made the symptoms of iron deficiency more evident on sweet gum, pin oak, and birch, as with manganese deficiency on red maple. Interveinal chlorosis, or yellowing between the veins due to a micronutrient deficiency, is a key distinction from overall leaf yellowing due to general moisture stress.
Soil conditions for the spring and fall planting seasons were unusually good. In most areas of the state, the soils were fairly dry and workable. These dry soils also resulted in the need for watering newly planted landscape materials in both the spring and fall. In addition, people were able to plant annuals earlier than normal in the spring, planting in cold soils in many cases. This resulted in numerous observations of phosphorus deficiency in plants.
Injury as a result of construction was reported periodically this year. Individuals desiring to build in a wooded area need to make plans for tree protection prior to construction. Landscapers should also make clients aware of the potential damage that could result from soil compaction, soil fill added over the root zone, and injury to the trunk. Tree species respond differently to the stress of construction activity. Informational resources on the tolerance of trees to construction injury should be consulted prior to the project.