Pamela J. Bennett
Jane A. Martin
Pamela J. Bennett, Ohio State University Extension-Clark County; and Jane A. Martin, Ohio State University Extension-Franklin County
The following is a compilation of note-worthy environmental and cultural plant problems for 1995. Observations were drawn from information provided in Ohio State University's Buckeye Yard and Garden Line (BYGL) reports, Plant and Pest Diagnostic Clinic samples (PPDC), David J. Shetlar's P.E.S.T. Newsletter, and reports from the Ohio Department of Natural Resources Monthly Water Inventory Report for Ohio.
Spring rains across much of Ohio helped to relieve some of the soil moisture deficits from a dry fall in 1994. Rain levels varied; by late May, Cincinnati was approximately 3" above normal for the year, while northern parts of the state remained dry. A warm period in mid-March resulted in temperatures in the 70s in parts of the state, followed by record lows on the night of April 4.
Temperatures moderated through May and June. Heavy rain episodes continued in parts of the state through June. At the end of the month, only the northeast and north central counties of the state were slightly below normal for the year. Rainfall totals for the rest of the state were near normal for the month.
Precipitation in July fell in the typical summer fashion as scattered showers and thunderstorms. Several storms were locally severe with heavy downpours, contributing to local urban and small stream flooding. Temperatures were above normal in July and August, reaching into the 90s.
Rainfall in the first 20 days of August resulted from the remnants of southern tropical storms that delivered heavy rain across parts of Ohio. Regional averages for the month ranged from nearly 6" above normal in the west central region to about an inch below normal for the northeast region. Overall, the state was 125 percent of normal for rainfall in August.
The last 10 days of August were essentially dry. Those soils that were saturated at mid-month were rather dry by the end of the month, due to 10 days or more without rain, coupled with temperatures in the 90s. By the end of August, the Ohio Agriculture Statistics Service reported that 41 percent of the state had adequate soil moisture, and 59 percent had soils short of moisture. September remained dry across much of the state.
On the night of April 4, temperatures dropped to 15 degrees F in Akron, 23 degrees F in Cleveland, 18 degrees F in Columbus, 17 degrees F in Dayton, and 21 degrees F in Cincinnati. Significant plant damage was reported across the state. Tip burn was noted on wintercreeper euonymus (Euonymus fortunei) and more intense foliar discoloration was noted on Japanese euonymus (Euonymus japonicus) and 'Wintergreen' boxwood (Buxus microphylla 'Wintergreen') in southern Ohio. Fully-open flowers of star and saucer magnolia were killed in southern and central Ohio; tipburn of petals on flowers in the bud stage was reported in northern Ohio. Forsythia flower quality was lessened in many locations where full flowering had taken place before the freeze. Flower damage to weeping cherry and other Prunus also in bloom in southern Ohio was noted. Nurseries and garden centers reported bud and tip damage to newly-shipped west coast materials such as boxwood and spruce.
Reports of suspected damage to plants from the winter of 1993-1994 continued. Interior stem discoloration due to stem cracks, presumably from the deep freeze of January 1994, was observed. Cultivar differences were noted. In BYGL 95-20, 9-7-95, it was reported that in a nursery visit, Acer rubrum 'Red Sunset' red maple looked fine; Acer rubrum 'Schlesingeri' had stem splits, many unhealed, that extended as much as 10 feet and longer on the trunks. Many of the trees had cracked and had fallen over at weak points during the preceding year and a half.
Extension agents and state specialists continue to receive calls regarding plant problems resulting from improper transplanting and post-transplant care. There were reports of plants being planted too deeply, mulched too heavily, watered improperly, and improperly sited, leading to eventual decline and death of the plant.
Lawn weed problems were prevalent during 1995. Although exact causes are subject to speculation, some theories were postulated. In areas of excessive rainfall, preemergent materials may have been leached. In dry areas, preemergent materials that were insufficiently irrigated may not have activated. Furthermore, weather conditions were excellent for germination of crabgrass and other weeds.
Problems continued to be reported on burning bush (Euonymus alatus). These included nearly complete defoliation and discoloration of leaves associated with severe spider mite infestations as well as environmental problems. In BYGL 95-20, 8-17-95, the following report was made -- quoting the Illinois Home, Yard and Garden Newsletter No. 16 -- and well described what we were also seeing in Ohio:
"The Plant Clinic has received a number of samples and calls concerning the rapid decline of burning bush plants. The samples have been examined for possible fungal canker problems, crown gall at the base of the plants, root injury and the like; but infectious problems do not appear to be at fault.
"The problem, then, may be root stress or root injury caused by moisture and temperature stress. These are not factors we can prove. We cannot find an infectious cause, and the problem is dispersed over a great geographic area, so the most logical cause is environmental stress."
Inquiries about artillery or shotgun fungus (Sphaerobolus stellatus) were common throughout the state. This fungus develops in decaying organic matter (such as mulch) and is typically noted in the spring and fall, when conditions are cool and moist. Tiny black specks, resembling insect feces at first glance, are actually mature spore masses expelled from fruiting bodies of the fungus. Spores have been found as high as the second floor of buildings. The specks, 1-2 mm in size, are difficult to remove from surfaces.