Pam Bennett, Barb Bloetscher, Joe Boggs, Jim Chatfield, Erik Draper, Dave Dyke, Dave Goerig, Tim Malinich, Jane Martin, Hannah Mathers, Pam Sherratt, Amy Stone, and Curtis Young
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August 25, 2005
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This is the twenty-first 2005 edition of the Buckeye Yard and Garden Line (BYGL).
BYGL is developed from a Tuesday morning conference call of Extension
agents, specialists and other contributors in Ohio.
BYGL is also made available on the Internet from the Ohio State University
Horticulture and Crop Science (HCS) in Virtual Perspective website
(http://bygl.osu.edu). Additional fact sheet information on any of
these articles may be found through the OSU fact sheet database (http://plantfacts.osu.edu).
BYGL is a service of OSU Extension and is aided by major support
from the Ohio Nursery and Landscape Association (ONLA), with additional
funding from the Ohio Chapter of the International Society of Arboriculture
(ISA) to the OSU Extension Nursery Landscape, and Turf Team (ENLTT).
Participants in the August 23, 2005 conference included: Barb Bloetscher (CWEPPDC); Joe Boggs (Hamilton/Piketon); Jim Chatfield (Center at Wooster/HCS); Dave Dyke (Hamilton); Dave Goerig (Mahoning); Joe Rimelspach (Plant Pathology); Dave Shetlar (Entomology); Amy Stone (Lucas); Curtis Young (Allen); and Randy Zondag (Lake)..
Additional factsheet information on any of these articles may be found
through the OSU Factsheet Database (http://plantfacts.ohio-state.edu/)
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WEATHER WATCH
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Joe Boggs reported that storms blew through the Cincinnati area over the past weekend. Along with some much needed rain, wind gusts were clocked at 60 mph. Storms also moved across northwest Ohio. Heavy rains fell in the early am, and again in the afternoon on Saturday, with some areas receiving over an inch of rain.
This is the weather summary from August 1 - 24, 2005.
| Weather Station |
Region of Ohio |
Ave. High Temp F | Ave. Low Temp F | Ave. Temp F | Normal Ave. Temp F | Total Precip " | Normal Precip " | | Avon |
NE |
82.7 |
64.2 |
N/A
|
N/A |
2.04 |
N/A | | Hoytville |
NW |
85.8 |
61.6 |
73.2 |
70.7 |
0.93 |
2.30 |
| Delaware |
Central |
88.4 |
65.1 |
76.3 |
72.9 |
1.82 |
2.95 |
| Miami |
SW |
87.6 |
67.1 |
76.7 |
72.2 |
2.56 |
1.96 |
| Jackson |
South |
89.9 |
63.5 |
75.7 |
72.4 |
1.37 |
2.91 |
For a link to the OARDC Weather Stations, check out: http://www.oardc.ohio-state.edu/centernet/weather.htm
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HORT SHORTS
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PLANTS OF THE WEEK
Read all about perennials, and landscape trees and shrubs in the new publications "Perennial Plants for Ohio" and "Landscape Plants for Ohio" published by the Ohio Nursery & Landscape Association (ONLA). The descriptions and photographs of plants were provided for this new publication by the OSU ENLT Team along with other industry plant lovers. These full-color publications are available at Buckeyegardening.com for $5.00. Click on "garden store" and then "onla plant guides." ONLA members can purchase these in quantities at a reduced price at onla.org .
* PERENNIAL OF THE WEEK Coreopsis spp. - Tickseed. This large genus includes plants of varying forms, sizes, and leaf and flower textures. Plants range in height from 6" low-spreaders to 24" upright plants with flowers suitable for cutting. Flower colors are typically yellow and gold, although white and pink exist in some species. Plants tend to flower all season long if deadheaded; while some, such as 'Moonbeam', will brighten the garden all season long without deadheading. 'Sunray' also blooms all season, grows to 18" in height, has golden-orange semi-double blooms, and is good for cut flowers. 'Creme Brulee' is a recent introduction that forms a 36" wide, spreading mound of bright green foliage. Small, butter-yellow flowers are produced in profusion from early summer to late fall.
*WOODY PLANT OF THE WEEK Acer griseum - Paperbark Maple. This maple is an outstanding small specimen tree with its bark and fall color features. Rounded to oval in form, the bark is cinnamon-brown to red, and with age flakes to provide a beautiful, graceful effect, especially on a blue sky, sunny, snow covered winter day. The three-part leaves are soft in texture and provide excellent orange-red fall color.
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BUG BYTES
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MIMOSA WEBWORMS TORCH HONEYLOCUSTS
Jim Chatfield reported that mimosa webworms (Homadaula anisocentra) are torching honeylocusts in northeast Ohio. Other BYGLers noted that there are pockets of high populations in the northwest and central parts of the state too. Larvae of this moth feed gregariously within webs spun over the foliage. They feed as skeletonizers and their damage causes leaves to turn orangish-brown and appear fire-scorched. It is these clusters of "torched" leaves, rather than the actual webbing, that usually draws attention to an infestation.
There are two to three generations per season in Ohio, and they typically overlap so that larvae may be present anytime from June into September. Also, female moths often deposit their eggs on nests from which they developed, so nests continue to expand and become more dense with silk and spent leaves from one generation to the next. Once nests become large and tightly woven, control applications usually fail to penetrate the thick webbing. The best time to control the caterpillars is earlier in the season, when nests are small and constructed of loosely woven silk.
Effective early season treatments include the naturally occurring bacterium, Bacillus thuringiensis (Bt), as well as other insecticides listed in OSU Extension Bulletin 504, "Insect and Mite Control on Woody Ornamentals and Herbaceous Perennials"
[ http://ohioline.osu.edu/b504/index.html ]. Although it may be getting too late to control mimosa webworm this season, it is not too late to get ready for next season. Landscape managers should note which trees are heavily infested so they can monitor those trees early next season.
 
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FALL WEBWORMS SACK TREES
Several BYGLers reported that fall webworm's (Hyphantria cunea) second act for this season is now becoming very evident in central and southern Ohio. While some nests are currently small and difficult to spot, other nests are large and very conscious.
Like the aforementioned mimosa webworms, fall webworms create nests by enveloping leaves at the tips of branches with silk webbing, and they only feed on leaves encompassed by the webbing. The caterpillars are cosmopolitan feeders and they may graze on more than 120 species of deciduous trees, including almost all species of shade, fruit, and ornamental trees found in Ohio. Joe Boggs reported finding nests on baldcypress. However, the caterpillars seem to be particularly fond of sweetgum, black walnut, elm, maple, and hickory, as well as ornamental fruit trees such as crabapple. Heavy infestations can cause complete defoliation of affected trees.
This moth has at least two generations in Ohio, and eggs hatch over an extended period of time in both generations. While each nest typically contains larvae of equal age, it is not unusual to find neighboring nests populated by a wide range of instars. Occasionally, a range of instars may be found within a single nest. Second generation nests are usually more numerous than first generation nests, unless first generation larvae were hammered by disease, parasitoids, or predators. Nests which produced second generation moths may also become much larger because first generation females often lay their eggs on or near the nests in which they developed.
If nests are few in number and easily accessible, the best control approach is to physically remove and destroy the nests and caterpillars. Otherwise, there are several effective materials listed in the OSU Extension Bulletin 504, "Control of Insects and Mites of Woody Ornamentals and Herbaceous Perennials" [ http://ohioline.osu.edu/b504/index.html ]. However, insecticides may also limit the impact of bio-allies. There are over 50 species of parasitoids, and 36 species of predators known to make a living off of fall webworm. In past seasons, parasitoids have proven to be very effective in reducing year-to-year populations of this defoliator.
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BUGS STINKING-UP TOMATOES
BYGLers reported that STINK BUGS are stinking-up gardens in parts of Ohio. Several kinds of stink bugs may be found feeding on vegetable plants. They normally cause little appreciable harm on most plants; however, their piercing-sucking feeding activity on tomatoes can seriously damage the fruit.
Feeding by these bugs produces yellowish-green, pinprick-sized spots on the surface of green tomatoes and pockets of hard, whitish, callous tissue beneath the skin at the puncture points. The spots on the skin and the corky tissue beneath the skin become more evident as the fruit ripens. The spots may vary in color on ripe fruit from green to yellowish-green to golden-yellow. Heavy feeding damage can cause tomatoes to have a golden appearance. Beyond causing direct feeding injury, the mouthparts of these insects can also carry yeast and other pathogens that may cause decay in the fruit. Once damage occurs, it is too late for control efforts.
Adult stink bugs are flattened, shield-shaped insects. They are either brown or green, and they have red, pink, or yellow markings. The immature bugs (nymphs) resemble adults but do not have developed wings. Eggs are drum-shaped with circular lids and are laid in clusters on foliage. When disturbed, sink bugs ... stink. The insect can emit a foul odor, presumably to deter predators and gardeners from getting too close.
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ROBBER BARONS AND PIRATES
This is the time of the year when insect predators typically become more evident with high populations supported by a season of blossoming prey populations. Two interesting predators with distinctly different hunting styles were noted by BYGLers this week. Joe Boggs reported observing ROBBER FLIES snatching yellowjackets out of the air in southwest Ohio. This smashing display of aerial acrobatics illustrates why some entomologists consider these flies the "fighter planes" of the insect world.
The species Joe observed has a narrow body that is about 1" in length, and long, strong legs. Its stout thorax appears slightly humped when viewed in profile. Each leg is tipped with two formidable tarsal claws that look and function like grappling hooks. The robber fly smashes into its airborne quarry which stuns the victim. This produces a snapping sound that may be heard several feet away. The fly then grasps its prey with its claws, and uses its piercing-sucking mouthparts to inject saliva containing neurotoxic and proteolytic enzymes. The enzymes paralyze the victim and digest the internal tissues. The fly then lands, and has an insect Slurpee.
Robber flies belong to the dipteran family Asilidae. With over a thousand species representing this family in North America, there is a wide range of forms and sizes. Adults of all species are predators and will attack a variety of insects including bees, wasps, grasshoppers, dragonflies, damselflies, and other insects. They often seize prey that is larger than themselves. Their larvae are also predaceous and live in the soil, or in decaying wood and other organic matter, where they feed on insect larvae.
Curtis Young reported observing PIRATE BUGS, a more diminutive and sneaky insect predator, prowling on flower heads in the western part of the state. These tiny hemipterans belong to the family Anthocoridae, and there are around 70 species found in North America. They also have piercing-sucking mouthparts, and most species are predators. The bugs are elongated and slightly flattened. Many species are black with white or greenish-white markings. Pirate bugs are tiny insects, measuring between 1/16" - 3/16" in length.
One of the most common pirate bugs found in Ohio is the INSIDIOUS FLOWER BUG (Orius insidiosus). This bug lurks within flowers to ambush unsuspecting pollinators. Its predacious nature is made evident by its thickened, mantid-like front legs which are used to seize prey. Pirate bugs will not seek human prey; however, they are known to deliver wicked bites on the probing fingers of flower-pickers. The level of pain produced by their bite is far out of proportion to the size of the insect. Flower enthusiasts are cautioned to look before they pick, and to avoid acting like insects.
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DRUGSTORE BEETLES POPPING UP
Drugstore beetles have been appearing in homes and causing some confusion. These small (1/16") brown beetles hide their head under a hood like covering, so that the head cannot be seen from above. Adults lay eggs in items which contain animal or plant products such as dog food, crackers, pasta, chocolate, spices, old mouse bait, leather, improperly prepared taxidermy specimens, potpourri, dried flower arrangements, hemp- based crafts, Oriental rugs, wasp nests, and carcasses. They were named from their habit of infesting teas and herbs sold in apothecaries.
Normally, this pest can be eliminated by finding the source of the infestation and discarding it. Valuable items can be frozen or heated which will kill the larval and pupal stage. Please refer to OSU HYG FactSheet #2083, "Drugstore and Cigarette Beetles" for more information. The female lays 300-500 sticky white eggs individually on items that the larvae will eat. Upon hatching, the small, white, C-shaped larvae begin feeding and grazing until they reach 3/16" and are ready to pupate. The adults also eat. Drugstore beetles are in the same family (Anobiidae) and similar in appearance to cigarette beetles which were so named for their fondness of tobacco products. Cigarette beetles are strong flyers and are often found in windowsills, as they are attracted to light.
Pheromone traps, sold as pantry pest traps can be used to catch these beetles, however they should be used to monitor populations, as the beetles are not all successfully intercepted. Drugstore beetles are less likely to fly than cigarette beetles and may not be caught as effectively in these traps.
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WINDSHIELD WIPE
BYGLers also ran into a few other insects and mites this week including:
*Several BYGLers in different areas of Ohio reported that hot, dry conditions this summer have conspired to produce bumper crops of the warm-season TWO-SPOTTED SPIDER MITE (Tetranychus urticae). Dave Shetlar indicated that it is too late for control measures to significantly improve the appearance of heavily damaged plants. He also noted that miticides may have a limited impact on reducing mite populations because adult females are ceasing their feeding and egg laying activity to climb down into the duff where they spend the winter. He recommended that heavily infested plants should be noted for close monitoring next season.
* Joe Boggs reported that the depredations of BALDCYPRESS RUST MITE (Epitrimerus taxodii) is commonly being mistaken for drought damage in his part of the state. High populations of this warm season eriophyid mite causes foliage to become rusty red. Inner foliage is usually affected first, with the green outer foliage serving to enhance the dramatic overall color effect. Unfortunately, it is too late for effective control measures since mites have already started to shift into their less vulnerable overwintering stage. As with the season-ending recommendation for two-spotted spider mites, infested baldcypress trees should be noted and closely inspected next season prior to the appearance of mite feeding symptoms.
*The PPDC has received several calls and samples regarding large white moths hanging out in Colorado spruce trees. Fortunately some of the samples included the moths, which were identified as female GYPSY MOTHS! Close inspection of the branches showed that something had chewed at least half the length of many of the needles along one section of the branch. One sample actually had the remnants of the gypsy moth caterpillar and pupal casing stuck in the needles.
Interestingly, although spruce trees are supposedly resistant to gypsy moth caterpillar feeding, the Colorado blue spruce is a favored host! All of the samples and emails were in the southeastern counties which are already infested with gypsy moth. Landowners in these areas should check their Colorado blue spruce trees and adjacent areas for the egg masses which have already been laid. Scraping and destroying the egg masses before egg hatch next spring will reduce the number of caterpillars next year. However, if you have applied to the Ohio Department of Agriculture for consideration to be included in the 2006 Gypsy Moth Suppression Program, be sure to leave all egg masses alone until the survey work is complete.
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DISEASE DIGEST
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BOTRYOSPHAERIA DIEBACK OF VIBURNUM
It is that time of year when it is common to see what looks like early fall coloration on plants, from red maples to burning bushes. This early coloration often indicates that the plant is stressed and that it is a good idea to investigate what might be wrong and at least to make a note that there is a history of developing problems on the plant. If the early coloration is on a doublefile or cranberrybush viburnum, especially if it is only on individual branches, make sure to check for Botryosphaeria canker on the stems back from the area of leaf discoloration. This coloring is the first sign of trouble. To check for Botryosphaeria canker or bot rot, look for roughened, cracked, darkly discolored areas on the stem. Also, when you cut into the stem, there is internal discoloration in the cankered area. Best control: prune out the cankered branches at a good node a foot or so back of the canker.
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TURF TIPS
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MORE TURF DISEASES!
Joe Rimelspach reported that GRAY LEAF SPOT has been diagnosed on sports fields and commercial sites in Pennsylvania. This disease occurs on the leaf blades of susceptible cultivars of perennial ryegrass, causing browning and collapse of the turfgrass. Severe outbreaks look as if the turf was burned with a blow torch!
Although it has only been found a few times in Ohio over the last few years, turfgrass managers in the buckeye state should be careful to follow prudent management practices to avoid adding stress to the turfgrass, and predisposing it to this serious disease. Use a balanced fertilizer with a slow release form of nitrogen, and mow often enough to remove less than 1/3 of the total length of the blade. Keep the mower blades sharp and reduce traffic as much as possible. Water early in the day, to knock mycelium off the leaf blades and allow the leaf blades to dry before dusk. Irrigate deeply and thoroughly keep the turfgrass turgid. Products labeled to manage gray leaf spot include: Azoxystrobin; Thiophanate-methyl; Chlorothalonil; Propiconazole; Trifloxystrobin; Triadimefon; and Polyoxin D zine salt.
RUST disease has also recently appeared on susceptible cultivars of perennial ryegrass and fescues. Irrigate and fertilize as prescribed above to keep these perennial pustules to a minimum.
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COMING ATTRACTIONS
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BYGLive! IN CINCINNATI
The sixth 2005 BYGLive! Diagnostic Walk-About will be held Monday, September 12, at Spring Grove Cemetery & Arboretum. This monthly hands-on training program focuses on diagnosing plant pest, disease, and physiological problems. Directions to the meeting location are as follows: enter Spring Grove Cemetery & Arboretum through the main entrance off Spring Grove Avenue; straight ahead will be an underpass - drive through the underpass; turn right at the first intersection; and travel approximately 100 yards to the meeting site on your left. For more information, call Joe Boggs at 513-946-8993.
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41st OHIO PLANT DIAGNOSTIC WORKSHOP
OSU Extension, Hancock County and the OSU ENLTT, with teachers Nancy Kronberg, Joe Boggs, and Jim Chatfield announce the next Ohio Plant Diagnostic Workshop, on Wednesday, September 14 in Findlay. The location is The Lodge at Riverbend in Findlay. For a registration form on this program of the latest in diagnostic issues and problems, contact Nancy at (419) 422-3851 or (kronberg.3@osu.edu).or send $30 per person to OSU Extension, 7868 C.R. 140, Suite B, Findlay, Ohio 45840. The program starts at 9:45 a.m. and runs until approximately 4:00 p.m. Rumors are that in addition to a "marvelous lunch" there will be a good deal of screaming by all. The 2nd Annual Hancock County Master Gardener Ice Cream Feast will be included!
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OSU/ONLA NURSERY & LANDSCAPE FIELD DAY
Grab your calendar and save the date! Dont miss this outstanding event at the Waterman Farm/Wittmeyer Conference Room, OSU, Columbus on Thursday, September 22. More information to come.
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BYGLOSOPHY
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"He who plants trees loves others besides himself."Thomas Fuller
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