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Pam Bennett, Barb Bloetscher, Joe Boggs, Cindy Burskey, Jim Chatfield, Erik Draper, Dave Dyke Gary Gao, David Goerig, Tim Malinich, Becky McCann, Amy Stone, and Curtis Young Buckeye Yard and Garden onLine provides timely information about Ohio growing conditions, pest, disease, and cultural problems. Updated weekly between April and October, this information is useful for those who are managing a commercial nursery, garden center, or landscape business or someone who just wants to keep their yard looking good all summer.

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Welcome to the BYGL Newsletter

May 22, 2008

From: Pam Bennett, Barb Bloetscher, Joe Boggs, Cindy Burskey, Jim Chatfield, Erik Draper, Dave Dyke, Gary Gao, David Goerig, Tim Malinich, Becky McCann, Amy Stone, and Curtis Young.

This is the 8th 2008 edition of the Buckeye Yard and Garden Line (BYGL). BYGL is developed from a Tuesday morning conference call of Extension Educators, Specialists, and other contributors in Ohio.

BYGL is available via email, contact Cheryl Fischnich [ [email protected] ] to subscribe. Additional Factsheet 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 ONLA (Ohio Nursery and Landscape Association) [ http://onla.org/ ] and [ http://buckeyegardening.com/ ] to the OSU Extension Nursery, Landscape and Turf Team (ENLTT). Any materials in this newsletter may be reproduced for educational purposes providing the source is credited.

BYGL is available online at: [ http://bygl.osu.edu ], a web site sponsored by the Ohio State University Department of Horticulture and Crop Sciences (HCS) as part of the "Horticulture in Virtual Perspective." The online version of BYGL has images associated with the articles and links to additional information.

Following are the participants in the May 20th conference call: Pam Bennett (Clark); Barb Bloetscher (Entomology/C. Wayne Ellett Plant and Pest Diagnostic Clinic (CWEPPDC)); Joe Boggs (Hamilton/Piketon); Jim Chatfield (OSU Extension Center at Wooster/ Hort and Crop Science); Dave Dyke (Hamilton); Gary Gao (Delaware); Michael Loos (Cuyahoga); Tim Malinich (Lorain); Dave Shetlar (Entomology); Dave Sprootman (Rainbow Tree Care, Minneapolis MN); Nancy Taylor (CWEPPDC); Shawn Wright (OSU Piketon Centers); and Curtis Young (Allen).

WEATHERWATCH - May 22, 2008

Wet and cool seems to sum up the weather reports from across the state this week. Counties in all regions were reporting higher than normal precipitation and cooler temperatures seem to be prolonging an early spring climate. Though, in checking the historical data, Shawn Wright reported that out of the last 15 years, 5 were actually colder.

The following weather information summarizes data collected at various OARDC Weather Stations spanning the dates: May 1-20, 2008, with the exception of the soil temperatures which are readings from Wednesday, May 21 at 6:00 a.m.

Weather Station Region of Ohio Ave. High Temp F Ave. Low Temp F Total Precip." Normal Precip. " Soil Temp F 2"/3" http://bygl.osu.edu/ Page 1 of 10 Welcome to the BYGL Newsletter 5/23/08 8:33 AM

Weather Station Region of Ohio Ave. High Temp F Ave. Low Temp F Total Precip." Normal Precip. " Soil Temp F 2"/3" Ashtabula NE 62.5 43.7 2.36" 2.2" 46.22 / 48.66 Wooster NE 65.9 45.7 2.33" 2.5" 53.56 / 54.62 Hoytville NW 66.5 47.6 2.87" 2.0" 45.88 / 49.05 Columbus Central 68.1 48.4 2.58" 2.7" 53.77 / 56.03 Piketon South 70.6 47.6 5.13" 3.0" 48.62 / 52.14

For more information, see: OARDC Weather Station

GROWING DEGREE DAYS - May 22, 2008

GDD is a measure of the daily maximum and minimum temperature and directly relates to growth and development of plants and insects. The GDD of any zip code location in Ohio is estimated using the GDD of ten OARDC weather stations and available on the web at the site below. The range of GDD accumulations in Ohio from north to south is 327 to 554. Following is a report of GDD for several locations around Ohio as of May 20, 2008: Painesville, 327; Cleveland, 344; Toledo, 361; Canfield, 352; Lima, 370; Wooster, 370; Coshocton, 404; Columbus, 455; Springfield, 421; Dayton, 430; Cincinnati, 504; Ironton, 525; Portsmouth, 527; and Piketon, 554.

To put these GDD accumulations into perspective, the following is an abbreviated listing of plant and insect species with their respective phenological event and average GDD accumulations at which these events occur. Due to variations in weather, temperature, humidity, etc., these events may occur a few days earlier or later than predicted by the average GDD. By looking at a city, town, or village near you from the above list, or visiting the above web site, you can see what could be taking place in the landscape around you.

Blackhaw viburnum, full bloom, 322; redosier dogwood, first bloom, 323; dwarf fothergilla, full bloom, 325; winter king hawthorn, first bloom, 328; lilac borer, adult emergence, 330; slender Deutsia, first bloom, 338; Japanese kerria, full bloom, 342; common horsechestnut, full bloom, 344; red chokeberry, full bloom, 351; doublefile viburnum, first bloom, 353; Pagoda dogwood, first bloom, 363; red Java weigela, first bloom, 365; black cherry, first bloom, 368; common sweetshrub, first bloom, 371; lesser peach tree borer, adult emergence, 372; Ohio buckeye, full bloom, 374; holly leafminer, adult emergence, 375; Vanhoutte spirea, full bloom, 406; euonymus scale (first generation), egg hatch, 406; black cherry, full bloom, 419; Miss Kim Manchurian lilac, first bloom, 422; locust leafminer, adult emergence, 437; doublefile viburnum, full bloom, 444; black locust, first bloom, 467; common ninebark, first bloom, 478; oystershell scale, egg hatch, 497; smokebush, first bloom, 501; arrowwood viburnum, first bloom, 534; American yellowwood, first bloom, 546; bronze birch borer, adult emergence, 547; black locust, full bloom, 548; American Holly, first bloom, 556; and mountain laurel, first bloom, 565.

For more information, see:

Growing Degree Days and Phenology for Ohio Understanding and Using Degree-Days

PLANTS OF THE WEEK - May 22, 2008

Read all about perennials and landscape trees and shrubs in the ONLA publications "Perennial Plants for Ohio" and "Landscape Plants for Ohio." The descriptions and photographs of plants were provided for these publications by the OSU ENLT Team along with other industry plant lovers. These full-color publications are available at [ http://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 [ http://onla.org ].

*ANNUAL PLANT OF THE WEEK. PANSIES AND VIOLAS - (Viola spp.) While many have bemoaned the cooler spring temperatures, these plants have been having a blast, blooming their pretty little heads off. Pansies and violas prefer cooler temperatures and begin to shut down when it gets warmer during the summer. However, in the fall, they make a big comeback and show off once more. There are numerous cultivars of these plants on the market today and some varieties are great for overwintering and presenting a great color show early in the spring. Ohio State University Extension Floriculture specialist Claudio Pasian conducted pansy and viola trials in the past; check out the results at: [ http://floriculture.osu.edu/trials/PansyPage.html ].

For more information, see:

Fall Pansy/Viola Trial

*PERENNIAL PLANT OF THE WEEK. IRIS OR FLAGS - (Iris spp.) "Wow!" can be used to describe the iris bloom in central Ohio at this time; these plants are absolutely beautiful. There are many species and cultivars of iris. Crested iris (I. crestata) usually blooms early in April and is a dwarf plant, growing to around 10" tall. It makes an excellent border or groundcover. Japanese iris (I. ensata ) has somewhat "flat-topped" blooms http://bygl.osu.edu/ Page 2 of 10 Welcome to the BYGL Newsletter 5/23/08 8:33 AM

dwarf plant, growing to around 10" tall. It makes an excellent border or groundcover. Japanese iris (I. ensata ) has somewhat "flat-topped" blooms that are usually ruffled. These bloom later, usually around late May in central Ohio. The German or bearded iris is the one most commonly known and is considered the old-fashioned iris. The flowers come in numerous colors and are quite noticeable in the garden. Another low-growing dwarf iris, I. pumila grows to around 12" tall with bicolored flowers. The Siberian iris has clean, narrow, dark green foliage and white, purple or blue flowers. These plants get around 2-4' tall and the foliage is a nice backdrop for other perennials all summer. After iris finish blooming, cut off flower stems; the foliage remains attractive for the season, barring any problems with pests. *WOODY PLANT OF THE WEEK. WHITE FRINGETREE (Chionanthus virgincus). Fringetrees were blooming in Lexington, Kentucky two weeks ago, and Gary Gao reported the start of bloom of this lovely small tree this past week in Delaware, Ohio. Jim Chatfield remembers when vegetable grower par excellence John Graf of Graf Growers in Copley called up to talk of this "wonderful tree next to his farm that he could smell a half-mile away." It was fringetree and Jim will always remember John when he inhales its fragrance. John Graf, himself a true force of nature, passed away earlier this May and we will all remember him each Spring as the crops develop and fringetrees prepare to bloom.

White fringetree is a small native tree 12-18' with outstanding fleecy white flowers. It has an open tree form, lustrous green leaves, and attractive egg-shaped blue fruits on female plants. Lacy white flowers are eye-openers in overall effect and very fragrant. One needs to plant males with females to get fruit. Air pollution and soil pH adaptable. Chinese fringetree (C. retusus) also has very attractive flowers.

For more information, see:

Deciduous Trees and Shrubs with All‑Season Interests

*THE WEEKLY WEED. GROUND IVY (Glechoma hederacea) takes center stage this week as callers reported this problem weed crawling across lawns and landscapes. Also known as CREEPING CHARLIE, this perennial weed's primary means of spreading is by creeping into new areas. The prostrate square stems of this plant root at the nodes making it difficult to pull or rake. Leaves are rounded and arranged oppositely on the stem. Both leaves and stems emit a strong odor when damaged. Purple flowers are produced in the leaf axils on more upright stems. Ground ivy prefers damp shady areas but will also grow in full sun. It tends to invade thin, unthrifty turf and neglected areas of the landscape. Though it can reproduce by seed, it usually crawls in from an already infested area nearby.

Small infestations of creeping Charlie can be controlled by pulling. Larger areas of infested turf can be treated with broadleaf herbicides. This approach will usually require two applications. Best results can be obtained by using herbicides containing a mixture of active ingredients, 2,4-D, dicamba and MCPP being the most common. Application can be made when the plant is beginning to flower in the spring, but better control is achieved in the fall when the plant is also actively growing.

In the garden, spot treatment with non-selective systemic herbicides will provide good control. Burn-down types of herbicides may not be as effective as new plants may reemerge from rhizomes. Once under control, maintain turf health to keep ground ivy from reinvading. For landscapes, keep a plant free zone at the edge of gardens to help prevent this weed from reentering unnoticed.

WHAT'S WRONG WITH THE ANNUALS?????

"Nothing in most cases" would be the answer to this question. Many annuals prefer warm soils and this simply isn't to be found in many places in Ohio at this time. People who got an early start and planted before Mother's Day weekend are finding that the annuals are just sitting there. Be patient and wait until the soil warms up - they will eventually take off. There are two potential problems that might occur if the soils don't warm up. If the soils are cold and wet (from recent rains), there is a possibility that the roots will rot or become diseased. If this occurs, pull them out and start over. The other problem that can occur in cold soils is a phosphorus deficiency in the plants. The leaves begin to turn a reddish color. It's usually not due to a lack of phosphorus in the soil so don't fertilize; when soil temperatures are cooler, the plants can't absorb the phosphorus and deficiency symptoms show. Again, patience is the answer; wait until the soils warm up.

RAINING MAPLE SEED

Raining maple seed was a concern of some people across the state this week. Flowers on maple trees usually go unnoticed early in the year. However, large numbers of maple samaras--a.k.a. helicopters, whirligigs--can make the tree look tan instead of green. As the samaras spin to the ground, they clog gutters, cover sidewalks and find their way into every crack and crevice on the modern automobile. This rapid exodus of seeds leaves the tree looking rather sparse; the maple had put so much energy into seed production that new leaves got the short end of the development stick. As a result, leaves are slower to develop and are smaller than normal. This thin canopy will continue to develop and probably not be noticed later in the season. Many factors contribute to the millions of seed that the maples produce. Good weather late in 2007 helped the tree produce a large quantity of flower buds. A lack of frost or freeze to kill the spring flowers or developing seed just added to the numbers. Had the weather conditions been different, the problem may have been no seed production. Unusually high seed set will undoubtedly be a problem in the future but for this year brush off the car, unclog the drains and be sure to keep the maple weeds pulled from the landscape.

http://bygl.osu.edu/ Page 3 of 10 Welcome to the BYGL Newsletter 5/23/08 8:33 AM

TO PHLOX OR NOT TO PHLOX

Those cheerful roadside flowers you are seeing now in white, pink, purple and shades in between, are phlox, right? Well, there are a number of phlox in gardens and woodlands right now, including smooth phlox (Phlox glaberrima). Some of these are probably showing up along roadsides, but what you are almost always seeing instead is DAME'S ROCKET (Hesperis matronalis). How can you tell the difference? It is easy. Dame's rocket is an alien species in the mustard family and has four petals and alternate leaf arrangement. Phlox in the Polemoniaceae has five petals and opposite leaf arrangement.

FOUR-LINED PLANT BUG

Joe Boggs reported that four-lined plant bug (Poecilocapsus lineatus) nymphs and their accompanying damage are appearing on a range of perennials and recently planted annuals in southwest Ohio. This sucking insect feeds on over 250 herbaceous plant species. The quick-moving nymphs are reddish-orange with black wing-pads. The appropriately named adults vary from yellow to green in color and have four black stripes down the wings. Like many plant-feeding Hemipterans, the four-lined plant bug injects enzymes into the plant causing cells to collapse. The bugs then feed on the resulting "slurry." The damage appears as small, round, black sunken spots which may coalesce into extensive blackened areas on infested leaves. The symptoms are commonly mistaken for a plant leaf disease.

There is only one generation per year; however, both the adults and nymphs are heavy feeders. High populations can produce significant plant injury. Targeting the early instar nymphs for control now will reduce the overall damage caused this season. Most pyrethroid insecticides labeled for the targeted host plant will provide control.

For more information, see:

University of Connecticut IPM Fact Sheet University of Minnesota Fact Sheet

ROSES BRISTLING WITH SAWFLIES

The distinctive "windowpane effect" caused by the feeding activity of BRISTLY ROSESLUG SAWFLY (Cladius difformis) larvae is now appearing on rose leaves in southwest Ohio. Similar damage can also be caused by two other sawflies: ROSESLUG (Endelomyia aethiops); and CURLED ROSE SAWFLY (Allantus cinctus). Joe Boggs noted that the bristly sawfly dominates; however, he is also seeing minor damage from the roselug. It is important to make a positive identification because the bristly roseslug is a "season-long" pest with as many as six generations occurring in Ohio. The curled rose sawfly has two generations per season, and the roseslug only one generation. Bristly roseslug sawfly larvae are pale green in color and covered with short bristles; however, the bristles are difficult to detect without magnification. Early instar larvae feed as leaf skeletonizers on the lower leaf surface. The upper epidermis remains intact and eventually turns white producing the "windowpane" symptom. Later instars feed between the main veins producing "see-through" leaves. High populations spawned by multiple generations of this sawfly can produce significant injury to roses. A soil drench application of imidacloprid (e.g. Merit) made now will help stem the tide of the damage caused this season by the bristly roseslug sawfly.

Curled rose sawfly larvae are dark green in color. They have rows of small white spots, arranged in bands around their bodies. True to their common name, the larvae curl when disturbed. Early instar larvae feed as skeletonizers on the lower leaf surface and they often leave behind the upper leaf surface, producing the "windowpane" effect. Later instar larvae consume entire leaves, leaving only the midvein. Mature larvae bore into the pith of pruned canes to pupate. There are at least two generations per season in Ohio, so this sawfly can cause recurring damage. However, roses will typically recover by mid-to-late season with little long-term harm.

Larvae of the roseslug sawfly are pale yellow-green in color. They feed as skeletonizers on the upper leaf surface, leaving the lower lead epidermis intact. The lower epidermis eventually turns white producing the "windowpane" symptom. There is only one generation per season, so plants quickly outgrow the damage making this sawfly the least significant of the three species. Indeed, damage caused by this sawfly seldom warrants control of this pest.

For more information, see:

University of Illinois Newsletter University of Minnesota Fact Sheet

HOLY OAK LEAVES!

Dave Shetlar noticed small holes made by the OAK SHOTHOLE LEAFMINER (Agromyza viridula) in several white oak leaves this week. The damage is most evident on newly expanding leaves, as the holes are aligned http://bygl.osu.edu/ Page 4 of 10 Welcome to the BYGL Newsletter 5/23/08 8:33 AM

white oak leaves this week. The damage is most evident on newly expanding leaves, as the holes are aligned when folding the leaf as it would have been before it opened.

Because they have sponging mouthparts, the adult female midge feeds by sticking her ovipositor (egg laying device) in the leaves then lapping up the juices that ooze from the wounds. After feeding awhile, the female will lay an egg in various leaves, usually along a vein. As the larva feeds within the leaf, the tissue surrounding it dies in an elongate shape, until it reaches the edge of the leaf where a blotch forms. When the larva has finished developing, it chews a hole and drops to the ground. Although two generations occur each season, only the early one is noticeable, as the adult only bothers newly opening leaves.

Although the damage to the tree is minimal, a large population can be alarming to a casual observer, as the holes continue to enlarge as the leaves expand. In some cases, the leaves can look like Swiss cheese, due to the number of holes. Once the leaves are full sized, it may be difficult to determine the cause of the holes, unless one looks closely at the rim around the holes. A small knob may be noticed, which usually has a pin prick sized oviposition hole.

Along with the holes made by the oak shothole leafminer, strong winds or late spring frosts while the leaves are still opening can cause a phenomenon called "tatters" in which the leaves are malformed and full of irregular holes. To date, this has not been reported in Ohio this spring.

Control is unnecessary, and usually too late by the time symptoms appear.

For more information, see:

Oak Shothole Leafminer Factsheet

WOOLLY BOOLLY BEECH

Joe Boggs reported that the leaves on some European beech (Fagus sylvatica) trees in southwest Ohio are becoming festooned with the white, waxy, flocculent material exuded from the bodies of the nymphs of the woolly aphid (Phyllaphis fagi). The aphid has no approved common name, but entomologists generally refer to it as the WOOLLY BEECH LEAF APHID. The aphid is a European native that retains its preference for European beech in the U.S. The woolly aphid appears to avoid American beech (F. grandifolia); however, it is sometimes mistaken for the similar looking BEECH BLIGHT APHID (Grylloprociphilus imbricator) that prefers American beech. Nymphs of the blight aphid also exude white, waxy filaments, and the aphid forms large colonies that first appear on twigs and branches, then on leaves. The blight aphids wiggle their abdomens in unison when disturbed giving rise to the unapproved common name "boogie-woogie aphid." Woolly beech leaf aphid colonies appear on leaves and occasionally creep onto surrounding twigs. The nymphs also wiggle when disturbed, but their "dance" is very subdued and unorganized.

Reports from Europe indicate the woolly aphid can cause significant injury to its beech host; however, such reports are rare in the U.S. The primary impact on European beech in the U.S. is the reduced aesthetics caused by the high contrast between the brilliant white aphid colonies and the lustrous dark green or dark purple beech leaves. The aphids also exude copious quantities of honeydew and droplets of this sugary, sticky substance creates a gummy mess on underlying beech leaves, sidewalks, building decking, slow-moving gardeners, etc. The deposited honeydew may become colonized with black sooty molds adding to the unsightly appearance of the goo. Honeydew deposits can be washed away with a coarse stream of water, and most insecticides labeled for use on European beech will reduce aphid populations if control is considered necessary.

CREEPING JENNY SAW FLIES!

Small, chalky white and green striped "caterpillars" were noted devouring the Creeping Jenny (Lysimachia nummularia) in Columbus the last two weeks. Although normally a pretty brilliant gold groundcover, the plants were disappearing quickly under the heavy pressure of these insects. Closer inspection revealed that the "caterpillars" were the larvae of a wasp, the LYSIMACHIA SAWFLY (Monostegia abdominalis).

Although little information was found on this creature, the sawfly larvae eats the leaves of several Lysimachia species including the wild and cultivated yellow loosestrifes (Lysimachia nummularia and Lysimachia vulgaris) and Creeping Jenny. The sawfly feeds by chewing sequentially larger notches along the edge of a leaf, until only a crescent shaped piece remains. Apparently only one significant generation occurs each year.

An interesting note is that the sawflies curl and readily drop from the leaves to escape predation, making detection difficult. Fortunately, although heavy populations of this larva can decimate a small planting, their populations only peak occasionally, and the plants usually recover. In the planting inspected, the wasps and ants were rapidly carrying the "savory treats" (sawfly larvae) away.

FIERY PREDATOR

Localized populations of a number of caterpillars have been unusually high this season in southern and central Ohio. Inevitably, this free ranging meat will attract meat eaters. One of the most common predators feasting on the caterpillar herds is the FIERY SEARCHER CATERPILLAR http://bygl.osu.edu/ Page 5 of 10 Welcome to the BYGL Newsletter 5/23/08 8:33 AM

meat will attract meat eaters. One of the most common predators feasting on the caterpillar herds is the FIERY SEARCHER CATERPILLAR HUNTER (Calosoma scrutator). The searcher is in the beetle family Carabidae, or "Ground Beetles."

The fiery searcher is one of the largest carabid beetles, measuring over 1 1/4" in length. The front end of the beetle, the business end, sports sickle-shaped mandibles used to reduce hapless caterpillars into beetle fodder. The beetle has long, purplish-black legs and antennae. The abdomen is almost rectangular, with the posterior end slightly pointed. The hardened front wings (elytra) covering the abdomen are metallic green with fine longitudinal grooves. The outer edges of the elytra are reddish-orange; a striking feature that is responsible for the fiery common name.

The fiery searcher lays eggs in the soil and the resulting elongated larvae also sport impressive mandibles that are likewise used to grind-down the bodies of other insects. The life cycle of the searcher is usually completed within one year; however, adults may live for 2 to 3 years, spending the winter beneath bark or in the soil.

The searchers hunt at night, and hide during the day. They are strongly attracted to lights which makes them an occasional accidental home invader. Joe Boggs reported receiving two phone calls in a row from homeowners who had experienced breaking and entering by these beetles. Given the extremely beneficial nature of the fiery searcher, such wayward intruders should be gently coaxed outdoors ... very gently, since they can bite and emit a foul odor when mishandled!

For more information, see:

University of Arkansas Arthropod Museum Note Clemson University Entomology Museum Note

WINDSHIELD WIPES - May 22, 2008

BYGLers also ran into a few other insects and mites this week, including:

*Dave Shetlar reported that BOXWOOD LEAFMINER (Monarthropalpus flavus) adults have emerged and are buzzing their namesake in central Ohio. The tiny midge flies look like reddish-orange mosquitoes. Adults can be targeted with a foliar application of acephate (e.g. Orthene). However, an application of imidacloprid (e.g. Merit) made as a soil drench is a more effective control. While fall is the ideal timing for this application, since it will also prevent damage from BOXWOOD PSYLLIDS (Psylla buxi), an application made now will kill the leafminer larvae as they begin to develop in their leaf mines.

*EASTERN TENT CATERPILLARS (Malacosoma americanum) and FOREST TENT CATERPILLARS (M. disstria) have reached late instar stages and they are now abandoning their hosts to go on crawl-abouts. Thus, both may appear unexpectedly on the walls or doors of buildings as well as on unusual host plants. Eastern tent caterpillars are covered in short, grayish-white hairs, and they have a distinct, unbroken white stripe down their backs. Forest tent caterpillars have short grayish-white hairs and a row of distinct white "foot print" or "keyhole" markings running down their backs. The markings are flanked by cobalt-blue lines running the length of the caterpillars' bodies.

*Jim Chatfield reported that ERINEUM PATCH "GALLS" created by the eriophyid mite Acalitus fagerinea on American beech leaves are now appearing in northeast Ohio. There is a debate as to whether the felt-like erineum patches are true galls. They appear to arise like scar tissue from leaf cell damage caused by mite feeding activity rather than by a gall-maker exuding chemicals to direct plant growth. Regardless, as the patches turn from their current green color, to gold, then to brown, they become very noticeable and are often mistaken for leaf spot or rust diseases.

*BAGWORMS (Thyridopteryx ephemeraeformis) spend most of their existence as an egg. These eggs are laid in the fall inside of their mother's bag. They pass the winter and much of the spring in this position, and now it is approaching their time to hatch and emerge into the world to begin their independent lives as caterpillars. Dave Sheltar reported that the start of bagworm egg hatch appears to coincide with the full bloom or the fading of full bloom of BLACK LOCUST (Robinia pseudoacacia). The black locusts have reached this point in southern Ohio and are approaching this state in central Ohio. Thus, now is the time to start monitoring bagworm infestations very closely for newly hatched caterpillars. These caterpillars are going to be extremely small, so it will take very, very close scrutiny to see these cats.

For more information, see:

Bagworms on Landscape Plants Bagworm And Its Control HYG-2149-90

MOIST CHAMBER - May 22, 2008

Recent moist weather certainly provided infection periods for the fungus (Venturia inaequalis) that causes APPLE SCAB OF CRABAPPLE and, sure enough, results of those infections have led to symptoms of scab on crabapples noted last week at the BYGLive! at Cox Arboretum in Dayton and on samples sent to Tim Malinich in the OSU Extension office in Lorain County.

A non-pathogenic fungus that nevertheless becomes a landscaper issue was noted outside the OSU Extension office in Knox County. The ARTILLERY or SHOTGUN FUNGUS (Sphaerobolus sp.) was shooting little black, tarry glebal masses of fungal tissue onto the siding of the building. Joe Boggs parked his car nearby during evening and morning ENLTT meetings at the office and noted his windshield was speckled. He http://bygl.osu.edu/ Page 6 of 10 Welcome to the BYGL Newsletter 5/23/08 8:33 AM

building. Joe Boggs parked his car nearby during evening and morning ENLTT meetings at the office and noted his windshield was speckled. He had a flashback to his West Virginia childhood heritage - this shotgun attack however left his windshield intact.

MAYAPPLE RUST

BYGLers continue to see this rust disease in woodlands as a spectacular annual reminder that plant pathogens interacting with plants is part of the fabric of nature, not just a landscape or garden aberration. The bright orange pustules of the mayapple rust fungus become evident on the parasol-like leaves of may-apple each May in woodlands throughout the state. The disease is seen as yellow spots on the upper leaf surfaces and incredibly bright orange pustules of the rust fungus itself on the undersurface of the leaves. In some cases these pustules result in major distortion and early senescence of the leaves. This is an autoecious rust disease, occurring only on may-apples, not going back and forth between two different plants such as with cedar apple rust (junipers and rosaceous hosts) or white pine blister rust (white pines and gooseberries). Populations of mayapples in the woods seem to handle the annual occurrence of this disease each year and no controls are recommended for these habitats.

Note: Two optional conventions were deliberately used in the item above for mayapples. You could call them mayapples or you could call them may-apples. Either the compound word or the hyphenated word is acceptable, though may apples as two separate words is not. Why? Because may-apples (Podophyllum peltatum) a plant in the Berberidaceae or barberry family, is obviously not a "true" apple (it is not in the genus Malus in the Rosaceae or rose family), and to indicate this, the word is properly denoted by either hyphenating or compounding. Similar examples are pineapple and osage-orange.

ANTHRACNOSE DISEASES

Anthracnose diseases continue to be noticed by many. Anthracnose diseases of a wide range of trees (e.g. sycamore, oak, ash and maple) are common (though not particularly severe in most locations) this spring, especially with the cool, wet conditions during leaf emergence of many tree species. These include many reports of anthracnose on sycamore (and much more mildly on London plane), on ash, on oak (especially white oak) and on maple. There is blotchy leaf discoloration associated with the major veins with all these anthracnose diseases.

However, sometimes this symptom is obscured on sycamore because of the more extensive blotching and wilting of the entire leaf.

BLUEGRASS BILLBUG CONTROL IN LAWNS

If you have not done so already, now is the time to treat for bluegrass billbugs in lawns. Billbug is one of the turf grass pests that can slip under the radar going undetected until after severe damage has already been done to the turf. The overwintered adult billbugs renew their activity in late-April to mid-May whenever soil surface temperatures reach 65F. Females begin laying eggs in grass stems after a short feeding period. After the eggs hatch, the grubs (larvae) begin tunneling in the grass stems, but because the grass is growing rapidly, their damage can go unnoticed for a period of time. Billbug damage usually begins to appear in late‑June and worsens through August when the affected turf simply turns straw colored, but this damage may also be overlooked because this is the time when summer drought stress is common and grass may appear to be going dormant. One may not realize the turf has been damaged until after the rains return at the end of summer, but the turf does not rebound as would be expected.

Additionally, light infestations in lawns often produce small dead spots that look like the turf disease, dollar spot. Sometimes the damage looks like irregular mottling or browning in the turf. Heavy infestations can result in complete destruction of the turf, usually by August. The major problem with billbug damage is that it looks like a variety of other problems. Most turf managers confuse billbug damage with drought, disease, chinch bugs, greenbugs or white grubs. Billbug damaged turf turns a whitish‑straw color rather than the yellow caused by greenbugs. Soil under damaged turf is solid, not spongy as in white grub attacks. To confirm billbug attacks, do the "tug test," grasp the affected turf and pull upward. If the stalks break easily at ground level and the stems are hollowed out or are full of packed sawdust‑like material, billbugs are the culprit.

Products containing carbaryl (e.g. Sevin, High Yield Lawn and Insect Killer Granules) can do a pretty good job on billbug larvae that have exited grass stems, but these larvae have already done considerable damage before exiting to the soil. Those larvae that remain in the crowns and thicker stemmed rhizomes may not be impacted. Better products for current treatments would be those containing imidacloprid (e.g. Merit, Bayer Advanced Season Long Grub Control, GrubEx, etc.). These products need to be applied between late May and the third week of June. If conditions become drier into June, the application should be followed immediately by 3/8-1/2" of irrigation. Halofenozide products (e.g. MACH2, Scotts Season Long Grub Control or Spectracide Grub Stop Once and Done) can also be used, but they need to be applied before the third week of May to be effective. As you get further into June, these rescue treatments will become less and less effective. Professionals should also consider using imidacloprid plus bifenthrin (e.g. Allectus) or clothianidin (e.g. Arena) for rescue treatments. For more information on billbug and other turf grass pest management, refer to OSU Extension bulletin L-187, "Management of Turf Pests."

For more information, see:

Management of Turfgrass Pests Weeds, Diseases, and Insects Billbugs In Turfgrass HYG-2502-91

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CORE AERATION IN LAWN

Core aeration, also referred to as aerification, is the process where hollow tines are used to remove plugs of thatch and soil from the lawn and deposit them on the surface. Once the plugs of soil are deposited on the surface, rainfall or irrigation will incorporate the soil into the thatch layer. This soil addition to the thatch layer will improve the environment in this area resulting in increased microbial activity and thatch breakdown.

The process of core aerification pulls plugs which are usually 2-3" in length with a diameter of 1/2-3/4". Ideally, at least 8-9 plugs should be pulled per square foot of turf. With some aerifiers, this may mean making more than one pass over the lawn to achieve the desired number of holes. The plugs should remain on the lawn and be allowed to disperse into the canopy. Aerification can be performed in the spring (April or May) or in the fall (September or October) or just about any time when soil is not too dry or too wet.

For more information, see:

Thatch: The Accumulation in Lawns HYG-4008

SAMPLING 101

Over the next weeks and months, BYGL will feature tips on sending plant samples into the OSU CWEPPDC.

1. Obviously, many times you can only sample a small portion of a plant, but when large numbers of small plants are affected, collect entire plants, including roots. If five hundred rhododendrons are going down, do not just send a leaf or two. Dig plants to keep roots intact, rather than pulling the plants out of the ground. Remove excess soil by gently shaking or washing with water. Do not wet leaves or stems. Wrap roots so that soil clinging to roots will not be loose in the package. Do not ship wet plants (let air dry first).

2. If only a portion of a plant is sampled, include the part showing symptoms. Also, when possible, collect about a pint of roots, soil and fine rootlets.

3. When only localized parts of plants are affected (leaf spots, stem cankers), ship several examples of the affected parts. Stem and branch sections should include a short section of healthy tissue so that the transition area between healthy and diseased tissue is included. For example, if collecting a sample to check for Verticillium wilt disease, select 1" diameter stem sections about 6" long, ideally from the area where the stem transitions between healthy and diseased tissue, rather than collecting completely dead stems.

4. If shipping, press non-woody plants or leaves on small twigs between paper and place between pieces of stiff cardboard. Place in a padded envelope. For succulent plants, samples packed in airtight plastic often decay before arriving in a lab. Place leaves between paper towels before packing. Use strong containers, filling spaces with shredded paper or other materials to cushion the sample in transit. Use rapid mail delivery for best results.

BORER ALERT!

Don't forget about the CLEARWING BORERS (Order: Lepidoptera, Family: Sesiidae) that impact our landscape trees and shrubs. The clearwing borer season most likely has begun in southern and central Ohio with the emergence of LILAC/ASH BORERS (Podosesia syringae) from infested ash trees and lilac shrubs. The lilac/ash borers are just the first of a series of clearwing borers to emerge in the late spring and summer. The emergence of adult clearwing moths can extend over long periods of time after the initial onset. As each of the different clearwing borers emerge, the trunks of their susceptible host plants should be treated with preventative insecticides at the appropriate times to prevent significant infestation or re-infestation.

Let this report serve as a notice to plant health managers that if they have not already done so, now is the time to get their clearwing borer monitoring traps out in the field to detect the emergences of each of the significant borers. These traps provide a relatively easy, but very effective method to keep track of these very important ornamental plant and fruit tree pests. Pheromones to bait these traps are readily available through a number of catalogs and websites.

LANDSCAPE DIAGNOSTIC WORKSHOP IN CENTRAL OHIO

OSU Extension in Delaware County is proud to present the 2008 Landscape Diagnostic Workshop in Delaware, Ohio on June 9, 2008. This will be an all-day program which features Jim Chatfield, Dr. Dave Shetlar, Dr. Gary Gao, and Amy Stone. Topics include: Diagnosing Nutrient Disorders in the Landscape; The Most Damaging Insects of Herbaceous Perennials; 20 Infectious Diseases in the Landscape; Diagnosing Insects and Mites of Woody Plants in the Landscape; Emerald Ash Borer (EAB) Update; and EAB Hands‑on Training. The registration fee is $40.00 per person. The fee includes the program, handouts, breaks and lunch, and a certificate of completion. http://bygl.osu.edu/ Page 8 of 10 Welcome to the BYGL Newsletter 5/23/08 8:33 AM

person. The fee includes the program, handouts, breaks and lunch, and a certificate of completion.

The registration deadline is June 5, 2008. Space is limited to 80 attendees. Registration will be accepted on a first come, first served basis. Late or on‑site registration is subject to a $5.00 late fee. Please call OSU Extension at 740‑833‑2030 to confirm space availability before registering onsite. Follow this link [ http://delaware.osu.edu/horticulture/upcoming‑programs ] to download a program flyer or email Cindy Kaelber at: [ [email protected] ] for a program flyer.

TOTAL PLANT HEALTHCARE WORKSHOP

Greene County Master Gardener volunteers present this workshop on Thursday, June 5 from 8:30 a.m. to 4:00 p.m. at the OSUE Greene County office in Xenia. Special guest speaker is Roger Funk, PhD, Vice President and Chief Technical Officer of the Davey Tree Expert Company in Kent, Ohio. He will discuss the plant health care concept, how plants grow and respond to the environment, preventing growth factors from becoming limiting factors, plant nutrition, and the science of organics. The cost for the day is $40.00 and includes a great lasagna lunch. MG volunteer advanced training hours are available for this program; the general public is also invited. For more information, refer to the following website: http://greene.osu.edu or email Barb Mills at:[ [email protected]] or call 937-372-9971.

For more information, see:

Greene County OSUE Web Page

PLANT DIAGNOSTIC ACADEMY: July 9-11, 2008 Check out this 3 day class consisting of a hands-on approach to learning or refining plant diagnostic skills. These skills include discovering the process to properly diagnose plant problems, identification of woody plant diseases and detecting insect and mite problems. Determine how plants respond to cultural and environmental problems as hundreds of samples will be used to help participants identify symptoms. Diagnostic walks, to learn to really see the entire plant site environment, will also be a feature of this class. This experiential program will be held July 9-11, 2008 at Secrest Arboretum in Wooster, Ohio. Registration deadline is July 1, 2008, and classroom space is limited. Registration fee is $250 which includes all meals, snacks and class materials. Instructors include OSU Extension faculty Dave Apsley, Joe Boggs, Jim Chatfield, Bruce Cubberley (ATI), Erik Draper and Kathy Smith. For more information contact Kathy Smith at 614-688-3421 or visit: [ http://woodlandstewards.osu.edu/calendar ].

SCHNORMEIER GARDEN TOUR

This past week, thanks to Ted Schnormeier and his contact with Dan Herms, BYGLers and ENLTTers had a rare chance to tour the wonderful Schnormeier Gardens near Mt. Vernon and Gambier in Knox County, Ohio. Put on your calendar the dates of June 14-15, 2008, because these weekend dates will be the once-a-year opportunity for public tours of the gardens.

Schnormeier Gardens, started in 1996, provide world-class vistas on the 50 acres that include the Waterfall Garden, Stream Garden, Chinese Garden, Meadow Garden, Serenity Garden and Woodland Garden. There is a beautiful and peaceful Japanese tea house, a Chinese pavilion, numerous sculptures, many rare plants and a beautiful Frank Lloyd Wright-inspired home built in 1994. Ten lakes, wide swaths of emerald turfgrass swards, boulders, stone walls, and what Ted Schnormeier termed the "stairway to heaven" - rows of ornamental crabapples and pagoda dogwoods. A remarkable opportunity: June 14-15, 2008. Check out their website for further information and directions: [ http://www.schnormeiergardens.org ].

BYGLOSOPHY - May 22, 2008 "Don't knock the weather: nine-tenths of the people couldn't start a conversation if it didn't change once in a while." - Kin Hubbard

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Where trade names are used, no discrimination is intended and no endorsement by Ohio State University Extension is implied. Although every attempt is made to produce information that is complete, timely, and accurate, the pesticide user bears responsibility of consulting the pesticide label and adhering to those directions. http://bygl.osu.edu/ Page 9 of 10 Welcome to the BYGL Newsletter 5/23/08 8:33 AM

OSU Extension embraces human diversity and is committed to ensuring that all educational programs conducted by Ohio State University Extension are available to clientele on a nondiscriminatory basis without regard to race, color, age, gender identity, or expression, disability, religion, sexual orientation, national origin, or veterans status. Keith L. Smith, Associate Vice President for Ag. Adm. and Director, OSU Extension, TDD No. 800- 589-8292 (Ohio only) or 614-292-1868.

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