Several BYGLers reported that symptoms consistent with iron deficiency on pin oaks and manganese deficiency on red maples are a common sight in their parts of the state this season.  Iron deficiency on oak is characterized by yellowing between the veins, or "chlorosis," with the veins appearing as thin green lines.  Manganese deficiency symptoms on red maple also include chlorosis between the veins; however, the veins appear as broad, green lines.  Readers should note the phrase "symptoms consistent with."  A plant tissue analysis is the only way to learn with certainty that the symptoms are being caused by the deficiency of a particular nutrient.  The analysis is offered through most soil testing labs.

Arborists should also be cautious with making a quick diagnosis regarding the cause for the nutrient deficiency.  If a tissue analysis shows that an element is deficient in the leaves, the only thing that can said with certainty is the tree is unable to provide a sufficient quantity of the element to the leaves.  The exact cause may be related to a number of conditions, sometimes working in tandem.  Possible causes include:  the soil pH is preventing elements from being available to the tree; dry soils are preventing movement of elements into roots; root function is being disrupted by wet soils (drowning roots), soil compaction, or soil excavation; vascular flow in roots and stems is being disrupted by disease or injury; and of course, that element may in fact be deficient in the soil.

*ANNUAL - DAHLIA 'MYSTIC ILLUSION' (Dahlia hybrid).  The bright yellow flowers seem to jump off of the very attractive dark foliage of this eye catching plant.  How eye catching is it?  Steve Foltz, Horticultural Director, Cincinnati Zoo and Botanical Garden, states that it has been the most photographed plant at the zoo since it was first planted there in 2007.  Needless to say, it has been selected as one of the "Zoo's Best" in the zoo's annual plant trials.  This Proven Winners ^TM plant blooms from planting to frost, grows to a height of 18-36", and prefers full sun.  It has a mounding growth habit that works well in mixed plantings in the landscape.  This plant has exhibited very few insect or disease problems in 3 years of trials at the zoo.  For more information on this plant, including photographs, go to:  

*PERENNIAL - SHOWY STONECROP SEDUM (Sedum spectabile).  What grows 18-24" high, tolerates full sun, dry sites, and blooms in late summer when most other perennials are long past their prime?  It is our perennial of the week, Sedum spectabile or showy stonecrop.  As a member of the Crassulaceae family of plants, the showy stonecrop grows upright stems that have thick, fleshy, obovate shaped leaves.  Several cultivars are available with red, blue-green or variegated foliage.  The flowers of showy stonecrop sedum are either pink, red, or white cymes that can grow up to 6" across.  This plant is hardy to Zone 3 and is best used in rock gardens, borders or in groups of three or more.  Sedum is easy to grow and doesn't seem to have any serious pests. 

*WOODY - BLACK TUPELO (Nyssa sylvatica).  This is one of Ohio's most beautiful native trees.  Black tupelo is a medium to large tree that some say has a similar growth habit as the pin oak (Quercus palustris).  It is somewhat pyramidal when young, and as it matures, develops an irregular, rounded canopy which is covered with lustrous dark green simple, obovate shaped leaves that consistently turn vividly bright yellow to orange to scarlet to purple colors in the fall.  The black tupelo flower is not ornamentally effective but somewhat fragrant.  It develops into a small drupe which is favored by many species of birds and mammals.  The tree is also commonly called the BLACKGUM, or SOURGUM, and prefers moist, well drained acidic soils.  It is an acceptable street tree and/or excellent specimen tree. 

*THE WEEKLY WEED - COMMON TEASEL (Dipsacus fullonum (Synonym:  Dipsacus sylvestris).  This weed is also known as WILD TEASEL, FULLER'S TEASEL, and VENUSCUP TEASEL.  The spiny flower head that persists throughout the year is one of this week's weed's most noteworthy characteristic.  This biennial reproduces by seed that germinates in late summer and early fall and overwinters as a basal rosette.  The leaves are puckered in appearance.  Flowers are present July through September of the following year.  The flower head is egg-shaped, covered with small spines, and has large bracts that curve upward from the bottom.  The white petals are tubular, with purple lobes, giving the head a purple thistle-like look.  Teasel is often found along roadsides, low maintenance stands of turfgrass, and in meadows.  It is usually not a problem in cultivated and cared for landscapes. 

For more information, see:

• USDA Information Center

We are tentatively identifying the growths as galls produced by an eriophyid mite.  There are small chamber-like voids inside the base of the individual knob-like growths which indicate they may be produced under the direction of some form of mite or insect gall-maker.  Eriophyids are known to stimulate a profusion of plant growths (e.g. rosettes, witches'-brooms) on certain hosts.  However, no eriophyids were found in the chambers.  It was speculated that the mites may have completed their development and vacated the chambers, but without finding mites, the connection is tenuous.

We are asking BYGL readers for help in learning how common and widespread this problem is on Caryopteris in Ohio.  If you have observed such growths (see the web version of the BYGL for images: http://bygl.osu.edu/, please contact Joe Boggs with your geographical location, the cultivar (if known), and your observations such as whether it's a landscape planting or nursery stock, the amount of damage, etc.  Joe's e-mail address is:  This e-mail address is being protected from spambots. You need JavaScript enabled to view it .

For more information, see:

• University of Arkansas, Department of Plant Pathology Plant Health Clinic News

Several BYGLers reported that Extension offices are buzzing with calls concerning CICADA KILLER WASPS (Sphecius speciosus) making low-level flights over sand volleyball courts, lawns, and bare areas in landscapes.   These are the largest wasps found in Ohio, measuring 1 1/8-1 5/8" in length.  The males are notoriously territorial and will chase after other males as well as picnickers, golfers, volleyball enthusiasts, and gardeners.  Fortunately, it's all a rouse since the males lack stingers.

The wasps have black bodies that are marked with yellow to white patches on the first three abdominal (rear part) segments.  The head, thorax and legs are rusty red and the wings russet-yellow.  As with all hymenoptera (wasps, bees, etc.), only the females possess stingers (ovipositors); however, they are not aggressive.  The females spend their time digging and provisioning burrows with paralyzed cicada (prey).  The males spend their time establishing and defending territories that encompass females.  They will aggressively buzz any transgressor who dares to enter their territory; including people.

The females prefer to dig their brood burrows in sandy, bare, well-drained soil that is exposed to full sunlight.  Although the wasps are considered solitary, they all practice the same nesting behavior.  Thus, it is not unusual for there to be numerous burrows, and wasps, in relatively small areas.  Cultural practices that promote a thick growth of turfgrass usually eliminate a cicada killer infestation in a lawn in one or two seasons.  Landscape infestations may be reduced by mulching or by adding plants to shade the soil.

These giant wasps are considered beneficial since they are the nemesis of ANNUAL DOG-DAY CICADAS (Tibicen spp.).  Indeed, an abrupt halt in the staccato "singing" of a cicada, often punctuated by a high-pitched screech, usually means a cicada killer has committed an insecticidal act.  It is no accident that the arrival of the wasps coincides with the arrival of the dog-day cicadas.  Since these are beneficial insects, chemical control should be reserved for severe infestations located in close proximity to human activity.  Following label directions, a dusting with carbaryl (e.g. Sevin), or a powdered formulation of a pyrethroid, around the burrows is normally effective in killing the wasps.

Reports of YELLOWJACKET and BALDFACED HORNET nests have swarmed into county and state offices this week.  At this time of year, the colony is teaming with workers and food is more difficult to access.  Yellowjackets especially seek more sweets and carbohydrates in the fall instead of the protein snacks they receive from fellow colony mates.  Hot weather adds to their tenacious attitude thus if the colony is disturbed or threatened, yellowjackets do not hesitate to convey their distemper with nasty stings.

Ohio has several species of hornets including the smaller ground dwelling yellowjackets (Paravespula vulgaris and P. maculifrons) and several aerial species of yellowjackets including the German yellowjacket, (Paravespula germanica) which make paper nests in wall voids or tree hollows.  Yellowjackets are easily identified by their vivid black and yellow-striped bodies, although each species has its own distinct banding pattern.  Baldfaced and European hornets build large paper nests, the baldfaced hornet's nest typically seen hanging from tree branches.  The European hornet's nest is usually enclosed in a void or hole in the ground and made of wood fiber.

Cicada killers are the largest hornet and the least likely to sting.  Instead they are busy scooping up cicadas to drag into their tunnels in loose soil.  All can be identified by their relatively thick, heavy body and rather colorful stripes.

All species of hornets are beneficial as they are great predators of common garden pests such as cutworms and other soft bodied insects (except for the cicada killer), however at times they build their nests in buildings or where people play, eat or walk.  In these situations, treatment may be required.

To date, the best control for nests in the ground or other accessible entrances, is carbaryl dust (Sevin) or the newer product, Eight.  Make sure that the dust will not blow or land anywhere except into the colony's entrance hole.  Wear gloves, a dust mask, and an instrument which will funnel the dust into a small hole, then in early morning, blow 5-8 puffs of the insecticidal dust into the entrance hole.  Bees and wasps are rather lethargic and slow moving after a cool night.  Leave the area immediately after blowing the dust and avoid it until the following day.  The yellowjackets should have declined dramatically.  Never dump gasoline into a nest near a structure as concentrated fumes could cause an explosion!  Keep in mind that all bee and wasp nests except for the honey bee colony will die after the first few hard frosts. For the baldfaced hornets' head-sized paper nests, direct an insecticidal wasp spray that will shoot 50 feet away using the same precautions as above.  Because of the tenacious habit of these black and white hornets, contacting a reputable pest control professional is a sage alternative.

Both Dave Goerig and Gary Gao received phone calls about grape black rot.  Black rot is caused by a fungus and is one of the most damaging grape diseases in the Midwest.  Symptoms of black rot first appear as small yellowish spots on leaves.  As the spots (lesions) enlarge, a dark border forms around the margins.  The centers of the lesions become reddish brown.  By the time the lesions reach 1/8-1/4" in diameter (approximately two weeks after infection), minute black dots appear.  These are fungal fruiting bodies (pycnidia) and contain thousands of summer spores (conidia).  Pycnidia are often arranged in a ring pattern, just inside the margin of the lesions.  Lesions may also appear on young shoots, cluster stems, and tendrils.  The lesions are purple to black, oval in outline, and sunken.  Fruit symptoms often do not appear until the berries are about half grown.  Small, round, light brownish spots form on the fruit.  The rotted tissue in the spot softens, and becomes sunken.  The spot enlarges quickly, rotting the entire berry in a few days.  The diseased fruit shrivels, becoming small, hard, black, and wrinkled (mummies).  Tiny black pycnidia are also formed on the fruit mummies.  The mummies usually remain attached to the cluster.  Black rot survives the winter in cane and tendril lesions and fruit mummies.

It is too late to control black rot of grapes for this year.  For next year, however, gardeners can destroy mummies, remove diseased tendrils from the wires, and select fruiting canes without lesions.  It is very important not to leave mummies attached to the vine.  Research has shown that mummies on the ground release most or all of their ascospores before the end of bloom.  Mummies left up in the trellis can produce ascospores and conidia throughout the growing season, thus making control of this disease much more difficult.  If only a few leaf lesions appear in the spring, remove these infected leaves. 

Grapes should be planted in sunny open areas that allow good air movement through the vines.  Proper row orientation to prevailing winds and good weed control beneath the vines also enable plants to dry more quickly during wet weather.  If black rot has been a problem in the past few years, it is likely that a good fungicide spray program will be needed as well.  Early season control must be emphasized.  The most critical period for controlling black rot fruit infections with fungicide is from pre-bloom (as flowers begin to open) through 3-4 weeks after bloom.  If controlled during this, the need for late season applications of fungicide for black rot control is eliminated.

OSU Extension Bulletin #940, "Midwest Home Fruit Production Guide," is a very handy reference for diagnosing fruit diseases, insects.  Gardeners can also find disease-resistant fruit cultivars.  Growing those fruit cultivars will definitely lessen the need for fungicide sprays.  Gary Gao is proud to tell BYGL readers that more than 1,700 copies of this bulletin have been sold!

Gardeners are also encouraged to check out the OSU Extension Bulletin #780, "Controlling Insects and Diseases in Home Fruit Plantings" for a list spray schedules, labeled pesticides and cultural practices of fruit pest management online at: http://ohioline.osu.edu/b780/index.html .  This bulletin can also be ordered from OSU Extension offices throughout Ohio.  Call first to confirm availability.

For more information, see:

• OSU Extension FactSheet on Late Blight of Potato and Tomato
• Cornell University FactSheet on Late blight on tomato

Initially the fungal blotches are a pale green color, eventually turning orange-brown with a yellow (chlorotic) border.  If the leaves are infected early, this disease can deform and wrinkle leaves as the leaf infections increase in size and number.  Unfortunately, the infected leaves soon turn entirely brown and fall off of the tree.  In view of the fact that this disease usually occurs after most of the annual growth has occurred for the season, Guignardia leaf blotch causes little harm to the health of vigorous trees.

For more information, see:

• Guignardia leaf blotch
• OSU Extension FactSheet on Leaf Diseases on Ornamental Trees and Shrubs

BYGLers in northern, western, and central Ohio reported that the fungal disease known as RUST is appearing on lawns, sports fields, and golf course roughs.  The fungus (Puccinia spp.) can infect all common turfgrasses used in the United States.  In Ohio, it is most commonly found on Kentucky bluegrass and perennial ryegrass.  The fungus seldom causes severe damage to turfgrass plants; however, it causes the epidermis of the leaf to rupture and release enormous amounts of orangish-yellow or rusty-colored spores.  The spores can become a real nuisance as they are easily rubbed off onto shoes, lawn mowers, pet fur, fingers, clothes, etc.

Rust usually affects turfgrass in the late summer and fall.  Infections are most commonly found on slow-growing turfgrass.  Juvenile turfgrass that is less than one year old is often more severely affected than mature established turfgrass.  The disease is especially severe on poorly fertilized turfgrass, drought stressed turfgrass, and on sites with compacted soils.  Under poor turfgrass growing conditions, the fungus infects the leaf tissue faster than new leaf blades are being produced so the diseased tissue is not mowed off.  Healthy turfgrass is capable of "outgrowing" the disease.

If the disease has been a problem in the past, it will most likely recur year after year unless growing conditions are improved.  Provide adequate water and fertilizer to keep the grass growing.  The turfgrass should be core aerated annually to improve water and fertilizer infiltration and uptake, reduce soil compaction, improve root growth, and to improve the overall growth and health of the turfgrass plants.  Management strategies should also include prevention through plant selection by using blends of resistant turfgrass cultivars.  The National Turf Evaluation Program (NTEP) provides free information on their website http://www.ntep.org/ regarding overall turfgrass cultivar quality and disease tolerance.

Fungicide applications will suppress the disease if the applications are made preventatively or during the very early stages of disease development.  Research at OSU has suggested that the sterol inhibitors and strobilurins show good to excellent efficacy.  However, since this disease is strongly linked to poor cultural practices as well as certain environmental conditions, relying on fungicides alone to suppress the disease sometimes yields disappointing results.  A fungicide program should be combined with improvements in turfgrass cultural practices.

The collective feeding activities of high populations of adult soft scales, such as calico scale (Eulecanium cerasorum) can cause significant harm to tree hosts.  However, landscape and nursery managers should be aware that the immature stage (crawlers) of soft scales also sucks plant juices.  While much smaller than the globular adults, the combined feeding activity of huge numbers of crawlers can likewise produce significant damage.

Randy Zondag and Joe Boggs reported that high populations of calico scale crawlers currently attached to dogwood leaves and honeylocust leaflets are causing leaves to turn yellow-to-brown in northeast and southwest Ohio, respectively.  Both noted that the leaf discoloration may be mistaken for moisture stress.  Calico scale is a globular, blackish-brown soft scale that is about 1/4" in diameter.  It is easy to recognize because of the distinct rows of squared, white patches on the back of the scale.  The tiny crawlers are tannish-brown, flattened, and oval-shaped.  They are attached to the midvein on the underside of leaves.  Like adults, the crawlers also exude sticky honeydew, although in lower quantities compared to adults.  As fall approaches, the crawlers will move to stems where they overwinter. 

Calico scale can infest a wide variety of deciduous trees.  The stems of off-colored trees should be closely examined for globular, reddish-brown, or dark-brown dead female scales.  Trials in Ohio have indicated calico scale can be managed using soil drenches of neonicotinoid systemic insecticides such as imidacloprid (e.g. Merit, Marathon), clothianidin (e.g. Arena), and dinotefuran (e.g. Safari) made from September into November.

For more information, see:

• Penn State Woody Ornamental IPM Fact Sheet

Many had hoped that the severe cold temperatures (-10 F and below for a couple of days and nights in a row) this past winter were going to lead to the demise of the bagworm (Thyridopteryx ephemeraeformis), and initially this spring, it looked like it was true.  However, a few reports of bagworm did trickle in earlier this growing season (BYGL 2009-15, July 16, 2009).  Now the bagworm has come out of hiding and is being discovered on a multitude of plants throughout the state, even the BugDoc, Dave Shetlar, got caught off-guard by a population on his own arborvitae in his landscape.  Dave reported that he discovered the "snake-sized" bagworms devouring his arborvitae just the other day, and they had already denuded a basketball-sized hole in the side of the plant.

Part of the reason that bagworms have avoided detection is that they seem to be developing relatively slowly this season compared to many previous seasons.  Bagworm development is spread very widely in their development from the southern to northern areas of the state.  A couple of weeks ago, Joe Boggs in the southern part of the state and Curtis Young in the northern part of the state, compared bagworm sizes and discovered that they were immensely different in size (Joe's were 1" and larger in size and Curtis' were 1/2" and smaller in size).  Although Joe's were bigger, they were still smaller than what would typically be observed at that time of the year.

The main point of this article is, if you have not recently checked your bagworm susceptible plants for developing bagworms, you should do that SOON!  Remember that the bagworms can blend into the plants they are feeding on because they incorporate pieces of the host plant into their bags and the fresher the material is, the more it will camouflage them making it difficult to see them.

Traditional insecticides must be used at this time to get satisfactory results.  Refer to OSU Extension Bulletin 504, "Insect and Mite Control on Woody Ornamentals and Herbaceous Perennials" for details on effective insecticides.

For more information, see:

• OSU Extension FactSheet on Bagworm
• Universtiy of Kentucky FactSheet on Bagworm