Pam Bennett, Barb Bloetscher, Joe Boggs, Jim Chatfield, Erik Draper, Dave Dyke, Gary Gao, David Goerig, Tim Malinich, Amy Stone, and Curtis Young.
|
|
July 13, 2007
|
|
This is the Fifthteenth 2007 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 July 11, 2007 conference included: Barb Bloetscher (Entomology/C. Wayne Ellett Plant and Pest Diagnostic Clinic (PPDC)); Joe Boggs (OSU Extension Center at Piketon/Hamilton-Clermont); Jim Chatfield (OSU Extension Center at Wooster/Hort and Crop Science); Gary Gao (Delaware); Tim Malinich (Lorain); Becky McCann (ABE Center); Dave Shetlar (Entomology); 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/)
|
WEATHER WATCH
|
The following weather information has been summarized from data collected from July 1-10, 2007. BYGLers have selected six locations to highlight different regions of the state to be included each week as seen in the table below. Additionally, there are weather station sites in Avon (Lorain County), Madison (Lake County), Perry (Lake County), at the Muck Crops Research Station (Huron County), at the North Central Research Station (Sandusky County), and at the Western Research Station (Clark County). The weather data collected from all the sites can be seen at http://www.oardc.ohio-state.edu/newweather/ .
| Weather Station |
Region of Ohio |
Ave. High Temp F |
Ave. Low Temp F |
Total Precip " |
Normal Precip " |
| Ashtabula |
NE |
79.9 |
55.4 |
0.0" |
1.0" |
| Wooster |
NE |
83.9 |
57.9 |
0.97" |
1.7" |
| Hoytville |
NW |
86.5 |
60.1 |
0.15" |
1.4" |
| Delaware |
Central |
96.2 |
49.0 |
0.62" |
1.5" |
| Piketon |
South |
86.0 |
59.5 |
0.32" |
1.4" |
| Jackson |
South |
86.2 |
57.8 |
0.67" |
1.9" |
|
|
|
|
|
|
|
|
HORT SHORTS
|
PLANTS OF THE WEEK
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 .
*PERENNIAL PLANT OF THE WEEK. LILY (Lilium spp.) is the perennial plant of the week. This large group of plants includes many types, but the Asiatic and Oriental hybrids are the most popular, each with an extensive selection of cultivars. These vertical plants grow to a height of 2-6' and should be surrounded by shorter plants that can assist in supporting the lily stems. The foliage stem is lined with strap-like leaves and topped by a few to several blossoms that nod downward. Colors range from white, yellow, orange, scarlet, rose, pink to bi-colored blooming in early to mid-summer. Excellent drainage is required to avoid bulbs rotting in wet soil. Some of the common cultivars include 'Mona Lisa,' Sorbet,' and Stargazer.'
*WOODY ORNAMENTAL OF THE WEEK. SUMMERSWEET CLETHRA (Clethra alnifornia) is the woody plant of the week. This increasingly popular shrub (6-8') has very fragrant, and narrow upright flower panicles which refreshes entire areas of the garden. It has attractive lustrous green leaves and delicate persistent woody fruits effective in winter. The native habitat of this shrub is shaded wet woodland. Hence, it should be planted in moist to wet sites. Fall color is yellow. Many cultivars include 'Hummingbird,' a 3-4 foot dwarf plant with 6" white flower panicles, 'Ruby Spice' with very ornamental rose pink flowers, and 'Sixteen Candles.'
|
|
BUG BYTES
|
DIGGING CHIGGERS
Several reports have emerged regarding chigger bites. The biting stage is actually the tiny, reddish 6-legged larvae (0.6 - 0.25mm), which crawl into hair follicles, causing considerable redness, itching, and swelling 2 - 6 hours later. The incessant itching may continue for 2 weeks, and although the mite may be dislodged by the scratching, secondary infections often occur.
Contrary to common belief, chiggers do not tunnel under the skin. Instead, they stay on the surface of the skin, or crawl to the base of a hair follicle to feed. They are usually found around the ankles, knees, waist, or armpits, where clothes fit more tightly. Once settled, the larva injects the skin with digestive fluids using its piercing, sucking mouthparts (capitulum), and then ingests this "slurry soup". After a few days, the larva drops off to enter its next life stage. Once it has emerged as a nymph, it will no longer be parasitic. Both the nymphs and adults feed on insects, and no longer feed on mammals.
To avoid being the victim of chiggers, avoid walking through brushy areas or wear long white pants with the socks pulled over the pant legs. Insect repellents such as DEET can help to ward off chiggers. Keep the area around homes and offices mowed to reduce the number of chiggers that are dropped near the building by animals, and check yourself immediately after walking in "wild" areas. It takes several hours for the chiggers to settle, so the tiny red mites may be seen running on your skin. Washing the 'bites' with warm soapy water and covering them will help to reduce infection. Calamine lotion and similar products will help to reduce itching. In certain cases, lawns can be sprayed by a professional, although it is usually not necessary.
 
|
|
MOSQUITOES BITE!
Although most of Ohio is still extremely dry, those areas that received some rainfall are now being plagued with mosquitoes! Several of the mosquito species (e.g. Aedes) cleverly lay eggs singly in objects such as a flower pot, gutter, or rotting tree stump, etc. The eggs hatch once they are flooded and a new generation of blood-sucking adults emerges in only 1-2 weeks.
Since many of the mosquito species only fly a few miles from their origin, it is important for homeowners and business people to remove or turn over items that hold water, correct or clean faulty gutters, and follow suggestions to preclude egg hatch.
Apply the following recommendations to protect yourself from being bitten:
- List item1
When mosquitoes are active, wear light-colored clothing which is less attractive to mosquitoes. Dark clothing as well as certain floral scents in lotions and soaps serve as "eat here" signs to mosquitoes. Wear long sleeved shirts, long pants, socks and shoes. Loose clothing is better than tight fitting clothing.
- List item 2
When possible, stay indoors during the early morning and late evening hours. These are the times when mosquitoes are most actively seeking a blood meal. Mosquitoes will also be active on cloudy, overcast days.
- List item 3
Avoid areas where mosquitoes are abundant, such as wood lots, weedy areas, and places with heavy vegetative growth. These are good resting areas for mosquitoes.
- List item 4
Cut high weeds around your home to reduce mosquito resting areas. Clean the gutters so that water does not stand in them.
- List item 5
Keep windows and door screens in good repair to keep mosquitoes out of your home.
- List item 6
When you cannot avoid being in places where and when mosquitoes are active, protect yourself with a repellent. The search continues for the most fool-proof, ever-lasting method to fend off mosquitoes, but don't hold your breath. Mosquitoes are attracted to carbon dioxide exhaled by large animals (e.g. people).
DEET (N,N-diethyl-meta-toluamide) is highly effective in repulsing mosquitoes; however, adults should use products with less than 30% DEET and children should use products containing 10% or less. Exposure to DEET should be limited and avoid spraying large areas of exposed skin. Always use DEET according to the manufacturer's instructions. Two new compounds have been recently added to the repellent arsenal. They are picardin (also known as KBR 3023), and the active ingredient in oil of lemon eucalyptus (a.k.a. p-methane 3,8-diol, or PMD). Products containing these repellents are not fool-proof or ever-lasting; however, they can provide some protection and relief from buzzing blood-suckers.
|
|
HOLELY SWEET POTATOES
Joe Boggs reported observing the typical damage on ornamental sweet potato vine (Ipomoea batatas) of the GOLDEN TORTOISE BEETLE (Metriona bicolor). The golden tortoise beetle and the CLAVATE TORTOISE BEETLE (Plagiometriona clavata) can both feed heavily on ornamental sweet potato vines. The typical damage caused by these beetles is multiple oval-shaped holes chewed through the leaves. Their feeding can produce enough holes through the leaves to detract from the ornamental value of the vines in a potted arrangement or garden. Thus, control may be necessary in some cases. The beetles are not difficult to kill and most insecticides registered as general garden sprays will do the job.
Look for tortoise beetles on the undersides of damaged leaves. Tortoise beetles are small (1/4"), oval, turtle-shaped beetles, thus the common name. The beetle is flat below, with the sides of the prothorax and wings flared out, giving the beetle an overall shape like that of a World War I army helmet. Coloration can vary by species. The clavate tortoise beetle is yellow to clear around the flare, with a dark brown, bull frog-like silhouette on its back where the legs of the frog extend out onto the flare. The golden tortoise beetle starts out as a dull orange color and changes to a brilliant metallic gold color when mating. When the beetle dies, its color reverts back to the original dull orange to tan color.
|
|
MITES ARISING
Several BYGLers reported continued escalation of mite populations on multiple trees, shrubs, perennials, and annuals in the landscape. Among the spider mites that tend to flare-up during periods of hot and dry weather conditions, the most notorious is the TWO-SPOTTED SPIDER MITE (Tetranychus urticae). However, other warm-season mites that can join the ranks as temperatures increase include: OAK SPIDER MITE (Oligonychus bicolor); MAPLE SPIDER MITE (O. aceris); and the HONEYLOCUST SPIDER MITE (Platytetranchus multidigituli).
Proper identification of warm-season mites is essential for developing pest management strategies, because mites such as the two-spotted spider mite and the EUROPEAN RED MITE (Panonychus ulmi) are very difficult to control due to issues with miticide resistance. Effective control of two-spotted spider mites can be accomplished with a mixture of abamectin (Avid) plus a 2% horticultural oil, or spiromesifen (e.g. Judo).
The other mites are much easier to control with an array of the other miticides available for mite management, rotating active ingredients to avoid resistance development. Homeowners are limited to insecticidal/miticidal soaps or horticultural oil (at 1.5%) which also conserves mite predators. Keep in mind that applications must target the lower leaf surface, where most mite species reside with the exception of the oak spider mite, and multiple applications are generally required for all the products.
|
|
YELLOWNECKED CATS
Joe Boggs reported that first generation YELLOWNECKED CATERPILLARS (Datana ministra) have reached the last instar stage in southwest Ohio. There are two generations in southern Ohio. The central and northern parts of the state usually experience an extended stay of only one generation. The caterpillars feed gregariously in colonies. First instars feed as leaf skeletonizers, and later instars consume entire leaves. The colonies typically focus their attention on defoliating one branch before moving to another. Small trees with multiple colonies can be rapidly defoliated.
When disturbed, yellownecked caterpillars will lift their anterior and posterior ends to make their bodies "U"-shaped. All instars have black heads, and a bright orange "neck" (prothorax) that gives them their common name. However, the caterpillars pass through different "color phases" during their development. First instar caterpillars are copper-colored with no distinct lines. Second instars have distinct alternating longitudinal yellow and orangish-red lines. Caterpillars in the final instar stage have alternating longitudinal black and yellow lines. Although all instars are hairy, the hairs are most evident during the last instar stage.
The caterpillars feed on a wide variety of trees and shrubs including: crabapples and other ornamental fruit trees, oak, maple, elm, beech, linden, honey locust, azalea, and boxwood. Early instar caterpillars are susceptible to the biological insecticide, Bacillus thuringiensis (Bt) (e.g., Dipel, Thuricide, or Caterpillar Attack). More traditional insecticides are needed to control later instars. A more direct (satisfying?) control method is to knock the caterpillar colonies to the ground and perform the "caterpillar dance." Thus far, no populations have developed resistance to this control method.
|
|
SCARLET OAK SAWFLY
Participants in this week's BYGLive! Diagnostic Walk-About in Cincinnati observed scarlet oak sawfly (Caliroa quercuscoccineae) larvae munching on leaves of a Shumard oak. Despite its common name, the sawfly may be found on pin, black, red, and white oaks as well as its namesake. The larvae skeletonize leaves by feeding gregariously side-by-side on the lower leaf surface leaving behind the veins and upper leaf epidermis.
Scarlet oak sawfly larvae are 1/4" - 1/2" long. Their semi-transparent bodies are flattened towards the front and tapered towards the back. The flattened area is trimmed in yellow with the gut contents visible through the cuticle making it appear as if a green line is running down the middle of its back. The tapered area is grayish-black to black. The larvae glisten in the sun and appear slug-like. This is due to their interesting habit of covering themselves with their own excrement which helps them stick to leaves and presumably dissuades predators. Their slimy appearance gives rise to another common name: oak slug sawfly.
The population found by the BYGLive! group was very small with only a few leaves damaged. However, any population of this sawfly should be monitored. In 1997 and 1998, areas of southeast Ohio saw substantial defoliation from this sawfly. There are 2-3 generations per season. The sawfly spends the winter as late instar larvae inside cocoons in the leaf litter. Development is completed in the spring. Once the black, fly-like females are mated, they use their saw-like ovipositors to insert eggs in rows along major leaf veins.
|
|
MILKWEED MENAGERIE
A number of plants in the milkweed family (Asclepiadaceae) have transcended "weed status" in recent years to join the ranks of plant-respectability. They are used in butterfly gardens, landscapes and naturalized areas. Their beautiful forms and flowers are enhanced by their special relationship with the MONARCH BUTTERFLY (Danaus plexippus).
However, monarch butterfly caterpillars may be joined by other insect herbivores that also enjoy a "special relationship" with their milky hosts. For example, participants in this week's BYGLive! in Cincinnati spotted the brightly RED MILKWEED BEETLE (Tetraopes tetrophthalmus) feasting on milkweed. The tubular-shaped 3/8" - 1/2" long beetles are orangish-red with black dots and streaks on their upper thorax and wing covers. These longhorned beetles, so named because of their long antennae, have a very descriptive scientific name. "Tetraopes" means "four eyes," and a close examination will reveal that the antennae divide the compound eyes causing the beetle to have four eyes. The adults feed on milkweed leaves and the larvae bore into the roots and stems.
Like the monarch, red milkweed beetles also seek protection from predators by accumulating in their flesh the alkaloid toxins, called cardiac glycosides (cardenolides), which are concentrated in the milkweed's sap. The same is true for MILKWEED TUSSOCK MOTH (Euchaetes egle) caterpillars; LARGE MILKWEED BUGS (Oncopeltus fasciatus); and SMALL MILKWEED BUGS (Lygaeus kalmii). Indeed, over 50 different taxonomic groups of milkweed-herbivorous insects accumulate milkweed toxins, and all advertise their toxic character through splashy coloration, usually involving an orange on black motif. A fascinating twist on the old axiom that "you are what you eat."
|
|
POTTER WASPS
Participants in this week's BYGLive! Diagnostic Walk-About in Cincinnati were also treated to viewing the handiwork of potter wasps (Eumenes sp.). As their common name describes, potter wasps fashion small rounded jug-like nests out of clay, and they attach the nests to leaves, twigs, or to structures such as window seals. The nests found on the Walk-About were attached to main veins on the underside of a sycamore leaf.
Potter wasps belong to the family Vespidae which includes paper wasps, yellowjackets, and hornets. The 3/8" - 3/4" long potter wasp females don't gather mud for their nests. They first collect water and then they mix it with dry soil using their mandibles. The mud mixture is then transported to the nest-making site where it is fashioned into individual pots ranging in size from 1/4" - 6/16" in diameter. The entire construction process may require a couple of hundred trips over several hours.
As the pot nears completion, the female lays a single egg attached by a thread to the inside surface of the pot. They then provision the pot with a caterpillar or beetle larva that has been paralyzed by a sting. Once provisioned, the pot is sealed with a clay plug leaving the hapless paralyzed prey to await an appointment with the wasp's hatchling larva. Thus, potter wasps are considered beneficial...to all but their prey!
|
|
FALSE SPIDER MITE
Damage from the false spider mite (Pentamerismus taxi) was seen this week on a Taxus yew sample sent to the PPDC. Typical stippling and yellowing of the newer needles was evident, and on closer inspection, the tiny mites were found at the base of the needles.
False spider mites are short legged with a flattened, squat body and "muscular" looking legs. This species is brick red with a black pattern on its back and is slightly smaller than the European red mite. A more commonly encountered relative is the privet mite, Brevipalpus inornatus. More information can be found at: http://www.ces.ncsu.edu/depts/ent/notes/O&T/flowers/note47/note47.html
|
|
DISEASE DIGEST
|
FIRE BLIGHT ON CALLERY PEARS
Joe Boggs noted that southwest Ohio has experienced heavy localized infections of BACTERIAL FIRE BLIGHT on Callery pears this season. While the bacterium responsible for this disease (Erwinia amylovora) is capable of infecting all members of the Rosaceae family, Callery pears were once considered to be somewhat tolerant of the disease, with spotty infections involving only 4"- 8" of the shoot tips. However, in 2001, and again in 2002, southern Ohio as well as Kentucky and Indiana saw widespread fire blight infections on Callery pears that produced noticeable branch blackening.
This year's heavy infections were predicted by John Hartman (Plant Pathology, University of Kentucky) in a report this spring in the Kentucky Pest News (Number 1120, March 26, 2007). At that time, he noted that environmental conditions could be favorable for bacterial infection. However, new growth on Callery pear in southwest Ohio was heavily damaged by the deep freeze in early April. Indeed, the blackening from freeze damage mimicked fireblight symptoms. Of course, the pears rapidly recovered causing some to believe the trees had dodged the fire blight bullet. Unfortunately, some trees recovered from the freeze just in time to receive a double-hit from fire blight! Whether or not the freeze contributed to the infection can only be speculated.
Fire blight symptoms include numerous infections (in some cases dozens or hundreds) along the stems where blossom clusters developed. Affected plant tissue is browned and blackened with discolored leaves remaining on the tree and shoots often wilted in a "Shepherd's crook"- like fashion. At this stage, control is problematic. However, the inherent tolerance of Callery pear to fire blight may prove to be a helpful ally. Based on past experiences with such infections, it is expected that the trees will recover without significant loss to stem growth.
|
|
TURF TIPS
|
JAPANESE BEETLES PARTY ON
BYGLers reported that calls continue regarding population of Japanese beetles are exploding and ravaging their favorite plants. In counties that received adequate amounts of rainfall last summer, the grubs were able to survive and emerge this year to continue the generation. In some counties, people have reported that they have "never seen so many beetles!" Indeed, some plants are being reduced to lacey silhouettes, as the Japanese beetles skeletonize the leaves.
Fortunately, a wide selection of insecticides is available and effective, as long as the directions are followed closely and the beetles are contacted with the product. Insecticides include: pyrethrins (deltamethrin, bifenthrin); carbaryl (e.g. Sevin); malathion; acephate; as well as insecticidal soaps and horticultural oils. Remember to avoid treating the flowers that are pollinated by butterflies or bees. Also remember that although people have reported collecting quarts of beetles in the Japanese beetle traps, the traps actually attract many more beetles than the bag catches!
The good news is that turfgrass entomologists predict that Japanese beetle numbers may be low next year if the drought continues, as the grubs cannot survive in dry soil under dormant turfgrass. Of course, it is a different story for irrigated turfgrass. Japanese beetles are day-time fliers that can look for green grass. Thus, owners of turfgrass that is regularly irrigated need to be vigilant for immigrating beetles seeking lush turf in which to lay eggs. Grub populations could become very dense in these areas.
|
|
CHAFERS TAKING IT ON THE CHIN
Dave Shetlar reported that he thinks NORTHERN MASKED CHAFERS (Cyclocephala borealis) have probably takin' it on the chin as far as their reproductive potential goes for this year. Their reproductive success has most likely been highly reduced by the extra-dry soils that have developed in many areas around Ohio due to the lack of significant rainfall for much of the late spring and early summer. Without adequate moisture in the soils, the eggs of the chafers will not survive.
Another chafer that may have also been hampered by this year's weather is the EUROPEAN CHAFER (Rhizotrogus majalis) that can be found in areas of northern Ohio. These areas experienced heavy rains for a period of time during the spring that coincided with the pupal stage of the European chafer which appears to have drowned the pupae in the soil (pupa would be unable to escape rising water in the soil). As evidence, Randy Zondag reported that he did not observe any major emergences of this chafer at all during the time that they should have been flying and mating.
|
|
GRUB NEMESIS ON THE WING
Joe Boggs reported that the BLUEWINGED WASP (Scolia dubia) is starting to appear over lawns in southwest Ohio. The wasps may be seen cruising a few inches above the turfgrass, often in loops or figure-8 patterns, searching for white grub indicators. They are excellent flyers and their flight plans sometimes cause them to be mistaken for the much larger, and different colored CICADA KILLER WASP (see below). The wasp will parasitize all white grubs, but is particularly fond of GREEN JUNE BEETLE (Continus nitida) grubs.
Once grub activity is located, the wasp will dig into the soil, or simply enter the green June beetle grub's burrow. It first stings and paralyzes the grub, then it lays an egg in the grub's body. When the egg hatches, the wasp larva first consumes the non-essential parts of the paralyzed grub, keeping the hapless grub alive and "unspoiled." Later, the ravenous larva applies the coup de grace, killing the grub. The immature wasp pupates inside the carcass from which a new wasp emerges.
The bluewinged wasp is around 1 1/4" in length. As the common name implies the wings as well as the head, thorax, legs, and first two abdominal segments are dark blue. The third abdominal segment is orangish-red with two side-by-side yellow spots on a black background. The remaining abdominal segments are orangish-red, and all segments are somewhat hairy. These solitary wasps may be found cruising turfgrass from June through early-October. They are not aggressive, and they are one of the "good bugs," so they should be conserved, not destroyed.
|
|
CICADA KILLERS ON THE LOOSE!
Several BYGLers reported that lawns, golf course sand traps, and sand volleyball courts in their areas are beginning to buzz with cicada killer wasps (Sphecius speciosus). As their common name implies, these giant wasps are the nemesis of 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 cicadas.
The wasps range in size from 1 1/8" - 1 5/8" long. Their black bodies 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 the females. They will aggressively buzz any transgressor who dares to enter their territory...including people. Of course, it's all a ruse since the males lack stingers.
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 sandy patches. Cultural practices that promote a thick growth of turf usually eliminate a cicada killer infestation in one or two seasons. 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.
|
|
INDUSTRY INSIGHT
|
HELP FIGHT EAB!
The need continues for dollars to support EAB research. Make a contribution to the American Nursery and Landscape Association, Horticultural Research Institute's special EAB Project fund. Contributions are tax deductible. Send your contribution to:
The EAB Project c/o
Horticultural Research Institute
1000 Vermont Ave, NW, Suite 300
Washington, D.C. 20005
|
|
INCOMPATIBILITY OF PESTICIDES A LIKELY CAUSE OF PHOTOTOXICITY
Gary Gao received a sample of apple with brown scabs and patches on the lower half of the fruit. The variety of apple, "Wealthy," was a fruit tree that is about 17 years old. The "strange" phenomenon started occurring last year according to the grower. After Gary Gao ruled out common diseases of fruit, he determined that the likely cause of this problem was the incompatibility of pesticides.
The grower may have mixed oil and captan together in one single spray, or both oil and captan were applied within 10 days of each other on the same plants. Sometimes, recommended pesticides applied at higher than recommended rates could also cause phytotoxicity. It is very important to follow label directions and also make sure the pesticides are compatible before they are mixed and applied. There is a pesticide compatibility chart in the "2007 Midwest Commercial Tree Fruit Spray Guide" and the "2007 Midwest Commercial Small Fruit and Grape Spray Guide." Both bulletins can be purchased from your local Extension office.
|
|
DROUGHT OF 2007
Droughts occur when there is more water leaving the soil than is being replaced. There are several factors that influence drought conditions including soil types, air temperatures, humidity, winds, and vegetation. The longer this condition lasts the more impact it has on our plants.
Drought impacts the landscape and nursery industry in several ways. First, plants become stressed and this can make them more susceptible to insect and disease problems. Newly planted materials tend to have the most problems since their root systems have been compromised during the planting process. Good scouting practices are important to discovering drought-related problems.
Second, irrigation water quality also tends to change during droughts. Water "hardness" and EC levels tend to climb as water evaporates from ponds, and water levels drop in wells. Also, pH can change. Be sure to monitor your water quality on a weekly basis and chart it so you can determine if action is needed.
Finally, the fear of losing plants during droughts may actually induce over-watering of plants. Remember that high temperatures and drying winds can cause some plants to wilt even if they have enough water. Always check soil moisture levels prior to watering to determine how much water is needed. Water should also be applied slowly over a long period of time to promote movement throughout the soil profile.
|
|
COMING ATTRACTIONS
|
10th ANNUAL GREEN INDUSTRY SUMMER SESSION SET FOR AUGUST 1
This August 1, 2007, all Northwestern Ohio industry professionals are invited to attend the 10th annual educational event, held at Owens Community College in Toledo, OH. Credits for ONCT, ASLA, ISA, Pesticide Applicators, and/or Master Gardeners will be available. Registration information can be found at http://abe.osu.edu/upcoming-events . If there are questions contact OSU Extension, Green Industry Center (419-354-6916).
|
|
40TH ANNUAL NURSERY GROWERS OF LAKE COUNTY OHIO (NGLCO) FIELD DAY
40TH ANNUAL NURSERY GROWERS OF LAKE COUNTY OHIO (NGLCO) FIELD DAY is August 14, 2007. The NGLCO Field Day will be held at Holden Arboretum in Kirtland Ohio. The program this year will feature garden tours of the 3500 acre Holden Arboretum, which is has a new feature- a garden railroad. Time and location information will be on the following website http://www.nglco.com/fieldday.htm . Master Gardeners and students will receive a special price. For further information call 440-241-7969.
|
|
BYGLOSOPHY
|
"The best friend on earth of man is the tree: when we use the tree
respectfully and economically we have one of the greatest resources of the earth." Frank Lloyd Wright
|
|
