Pam Bennett, Barb Bloetscher, Joe Boggs, Jim Chatfield, Erik Draper, Dave Dyke, Dave Goerig, Tim Malinich, Jane Martin, Hannah Mathers, Pam Sherratt, Amy Stone, and Curtis Young
|
|
August 18, 2005
|
|
This is the twentieth 2005 edition of the Buckeye Yard and Garden Line (BYGL).
BYGL is developed from a Tuesday morning conference call of Extension
agents, specialists and other contributors in Ohio.
BYGL is also made available on the Internet from the Ohio State University
Horticulture and Crop Science (HCS) in Virtual Perspective website
(http://bygl.osu.edu). Additional fact sheet information on any of
these articles may be found through the OSU fact sheet database (http://plantfacts.osu.edu).
BYGL is a service of OSU Extension and is aided by major support
from the Ohio Nursery and Landscape Association (ONLA), with additional
funding from the Ohio Chapter of the International Society of Arboriculture
(ISA) to the OSU Extension Nursery Landscape, and Turf Team (ENLTT).
Participants in the August 16, 2005 conference included: Pam Bennett (Clark); Joe Boggs (Hamilton/Piketon); Erik Draper (Geauga); Dave Dyke (Hamilton); Dave Shetlar (Entomology); Amy Stone (Lucas); Nancy Taylor (C. Wayne Ellett Plant and Pest Diagnostic Clinic (CWEPPDC)); 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
|
Summer continues on! This is the weather summary from August 1 - 17, 2005.
| Weather Station |
Region of Ohio |
Ave. High Temp F | Ave. Low Temp F | Ave. Temp F | Normal Ave. Temp F | Total Precip " | Normal Precip " | | Avon |
NE |
83.6 |
64.7 |
N/A
|
N/A |
1.22 |
N/A | | Hoytville |
NW |
86.8 |
63.3 |
74.8 |
71.1 |
0.80 |
1.65 |
| Delaware |
Central |
89.3 |
66.3 |
77.5 |
73.4 |
1.20 |
2.10 |
| Miami |
SW |
88.2 |
68.4 |
77.7 |
72.4 |
2.44 |
1.25 |
| Jackson |
South |
90.4 |
64.7 |
76.5 |
72.8 |
1.24 |
2.08 |
For a link to the OARDC Weather Stations, check out: http://www.oardc.ohio-state.edu/centernet/weather.htm
|
|
HORT SHORTS
|
PLANTS OF THE WEEK
Read all about perennials and landscape trees and shrubs in the new publications "Perennial Plants for Ohio" and "Landscape Plants for Ohio" published by the Ohio Nursery & Landscape Association (ONLA). The descriptions and photographs of plants were provided for this new publication by the OSU ENLT Team along with other industry plant lovers. These full-color publications are available at Buckeyegardening.com for $5.00. Click on "garden store" and then "onla plant guides." ONLA members can purchase these in quantities at a reduced price at onla.org
* PERENNIAL OF THE WEEK - Hibiscus spp. Hardy hibiscus makes a bold statement in the perennial garden. As a group, they can get to around 3 - 5' tall and equally as broad. The large dinner-plate size blooms start around mid-July and many times go until a hard frost. Plants are very slow to emerge in the spring, leaving one to believe that they didnt make it through the winter - be patient! Newer cultivars add additional garden features with the bronze foliage of 'Kopper King' and the cut-leaf foliage of 'Lord Baltimore'. One word of caution when planting hardy hibiscus, Japanese beetles love them so sprays are almost a must to keep them pest-free.
*WOODY PLANT OF THE WEEK - Gingko biloba. The gingko or maidenhair tree is an excellent choice for tough urban conditions. The unusual fan-shaped leaves are a beautiful green color thorughout the summer. Watch for the outstanding yellow fall color in October. However, you may have to be fast. This is one of those trees that give the right wind and rain conditions, it appears that all of the leaves drop at the same time! Be sure to plant male cultivars as the female fruits are quite messy - and smelly. Male cultivars include 'Autumn Gold', 'Lakeview', and 'Princeton Sentry'.
|
|
DARLING DODDER
Joe Boggs reported receiving a phone call from a homeowner describing a large mass of odd, yellowish-green, spaghetti-like filaments growing through and over English ivy in her landscaping. She indicated that at first she blamed her husband, an avid fisherman who stood ready to land the big one by periodically replacing all of his fishing line! However, Joe advised that she look past her husband and focus upon another culprit dodder.
Dodder (Cuscuta spp.) is one of the most fascinating plants to be found in Ohio, as well as one of the difficult to control. Some taxonomists contend that dodder is a member of the morningglory family (Convolulaceae), while others place it in the family Cuscutaceae. Its taxonomic traits are revealed when the plant produces flowers and fruit. Flowering occurs from early June to the end of the season, with plants producing numerous, small, white, pink or yellowish (depending on species) flowers. The fruit is about 1/8" in diameter, with thin papery walls. Each fruit contains 1- 4 seeds.
Dodder is considered a "broadleaf weed," although this is something of a misnomer since the plant lacks leaves. This is a true plant parasite, and it derives all of its needs from a plant host. As described by the homeowner, dodder appears as a twining yellow or orange plant that is sometimes tinged with purple or red. Occasionally, stems are almost white. The stems can be very thin and thread-like or relatively stout. It parasitizes various kinds of wild and cultivated plants, and is especially destructive to alfalfa, lespedeza, flax, clover, and potatoes. Ornamentals attacked included chrysanthemum, dahlia, helenium, Virginia-creeper, trumpet-vine, English ivy and petunias.
This is a summer annual plant, with seeds germinating in the spring. Once seeds germinate, the seedlings must attach to a host within a few days or they die. Upon finding a suitable host plant, the dodder seedling quickly twines itself around the host's stem. The basal part of the parasite soon shrivels away so that no soil connection exists. Water, minerals, and carbohydrates are absorbed from the host through haustoria, which are modified adventitious roots, that penetrate the stem of the host plant.
Dodder rarely kills its host plant, although it will often stunt its growth. However, dodder can be a serious disease vector. It has been shown to spread various "yellows diseases," and phloem-inhabiting "rickettsia-like" bacteria have been found to be present in the vascular tissue of dodder.
The plants wide host range and the long life of its dormant seeds make dodder hard to control and nearly impossible to eradicate. It is a prolific seed producer, and seed may be spread through irrigation water, on cultivation equipment, and in the manure of animals that have eaten dodder-infested plants.
Hand-pulling to control dodder is seldom effective. The plant attaches itself so firmly to its host that hand-pulling just breaks stems off leaving the point of attachment intact. As long as a portion of the dodder plant remains attached to the host, new stems can re-grow to produce flowers and seed. Pulling and destroying dodder-infected plants is recommended, however this must be done before seeds are produced. Preemergent herbicides applied to the soil in the spring prior to seed germination have proven to be effective. Check the product label to determine if the herbicide will control dodder, and follow the label directions.
|
|
COMMUNITIES IN BLOOM UPDATE
Pam Bennett reported on some of her travels while judging the International Small category for this competition. Judges visit a community and evaluate them on the following categories: Tidiness, Environmental Conservation, Heritage and Natural Resource Conservation, Community Involvement, Landscapes, Floral Displays, Urban Forestry, and Turf. The winner of this category is announce at the awards ceremony in September in Saskatoon, Saskatchewan.
This trip took Pam to Scotland and England, where the weather was indeed gloomy. It made her glad to get back to the 95F temperatures and 95% humidity! On the other hand, with the overcast weather, the plants and turf are quite green. Surprisingly, there were not a lot of diseases present. Black spot on roses and a bit of powdery mildew on a few perennials was about the extent in most gardens. In northern Scotland, the overcast weather also presents a challenge for tree growth; trees grow quite slow compared to what you would see in Ohio.
In Rosemere, just outside of Montreal, Quebec, the message to not use pesticides is loud and clear. Upon entering the city, one sees a billboard with a family all wearing gas masks and the phrase, "pesticides kill". This community was the first one in Montreal to ban the use of pesticides altogether. However, if there were to be a severe infestation of an insect, one could apply to the city for a permit and would then be told what could be used. In most cases, softer materials are recommended. Other alternative pest management strategies are also utilized. For instance, to get rid of chinch bugs in lawns, people use shop vacs. Otherwise, the people are learning a great deal about tolerance as well as switching to plants that are not susceptible to problems.
If you would like to travel and see some of the great things that Pam has recently shared in BYGL issues, and you are interested in becoming an America in Bloom judge, contact Pam at pjbennett@ag.osu.edu
|
|
BUG BYTES
|
BROWNED FOLIAGE - TOO LATE?
Dave Shetlar reported that he is getting a number of tree and shrub samples with foliage heavily damaged by lace bugs, spider mites, eriophyid rust mites, and other plant pests. Other BYGLers chimed in with a litany of late-season scourges. The group discussed what could be done at this point in the season, and whether or not it is simply too late to do anything that is meaningful to the overall health of the afflicted plants.
The general consensus of the BYGLers was that in situations where an entire tree or shrub is swathed in pest-induced browned foliage, it is too late for pest management practices to have a significant impact on reversing the obvious damage yet this season. However, plant cultural practices, such as proper watering, could have an impact on plant health by reducing added stress. Plant pests that may be managed with systemic insecticides, such as imidacloprid (e.g. Merit), should be investigated to learn if fall applications are effective in reducing populations next season. Finally, locations of trees and shrubs heavily damaged this season should be recorded, and marked for close monitoring next season.
|
|
MOSSYROSE GALLS: A HAIRY PROBLEM
Erik Draper and Joe Boggs reported observing several outstanding examples of mossyrose gall sprouting from the stems of roses in northeast and southwest Ohio, respectively. At this point in the season, these bizarre looking galls appear as large, spherical, hairy masses that resembled little reddish-green toupees sprouting from rose twigs. Follicularly-challenged BYGLers expressed a peculiar interest in this gall, and Joe noted that off the top of his head, he had never seen such fascinating growth.
Mossyrose galls are the handiwork of a tiny wasp (Diplolepis rosae) belonging to the gall-wasp family Cynipidae. The galls form on year-old rose twigs in the spring. At first, they are light green and moss-like, then they become "hairy" and reddish-brown as they mature. They are almost circular and may eventually grow to over 2" in diameter, hair included.
The wasps have only one generation per year, and they overwinter as immatures in the galls. New adults emerge in the spring. Proper timing for insecticide applications is not well known, so the most effective control involves pruning and destroying the current galls to reduce formation of new galls next season.
|
|
LAND OF THE GIANTS
Several BYGLers reported observing or receiving samples of a number of "giant" caterpillars 'tis the season. The "silkworm" caterpillars that belong to the family Saturniidae are the most common crawling giants found this time of the year. These include the larvae of CECROPIA, LUNA, and POLYPHEMUS MOTHS, as well as the dreaded HICKORY HORNED DEVIL, which is the larva of the beautiful ROYAL WALNUT MOTH (Citheronia regalis). Some of these caterpillars are capable of growing to impressive lengths, as long as 4 - 5".
Most of these giants are solitary night time feeders, spending the day in hiding. They cause little damage to their hosts. However, given their large size and sometimes impressive armaments, they can generate a significant "startle response" (bulging eyes, rapid heartbeat, etc.) when home gardeners find them on the underside of a leaf. The most notorious is the hickory horned devil.
The horned devil is an aggressive, hairless, blue-green caterpillar that is truly one of the "monsters" of the caterpillar world and could be described as frightening to behold. It has long, curved, orange spines with black tips on the first two thoracic segments, and 3 - 4 shorter black spines on the top of each additional segment. The devil's common name comes from its preferred host and its behavior. When disturbed, the caterpillar whips its head and thorax around giving the convincing impression that it is trying to impale the offending irritant - this caterpillar has great entertainment value! Aside from feeding on its namesake, the horned devil will also consume sumac, sweet gum, and walnut. However, as with all of the "monster caterpillars," the devil causes little harm to its host trees, so no controls are recommended.
|
|
NO-SEE-UMS FELT BUT NOT SEEN!
Several BYGLers received calls from exasperated gardeners reporting that they keep feeling sharp pin-pricks of pain on their legs, arms, and other areas of exposed skin while outdoors. No insects were seen fleeing the scene, and quick swats with a hand failed to laminate noticeable culprits to the palm. Many were frustrated at being unable to escape their torture, let alone identify their torturer.
Members of the midge fly family Ceratopogonidae are collectively referred to as "biting midges." These midges are tiny, measuring less than 1mm long. Their extremely small size is responsible for the common name "no-see-ums." Their intensely painful bites are responsible for many other common names invented by their victims, usually involving strings of expletives!
The painful bites of these diminutive blood-suckers are far out of proportion to their size because the midges are equipped with mouthparts that are far out of proportion to their bodies. Indeed, the tiny flies look like nothing but winged mouthparts! Their heavy-duty piercing-sucking mouthparts are used to penetrate skin, puncture blood vessels, and inject anticoagulants. The bites alone are painful, but the anticoagulants sometimes produce a long-lasting severe reaction including burning pain, and welts.
No-see-ums commonly torment beach goers, fishermen, and others who visit aquatic areas because the larvae of some species are aquatic. However, the immatures of other species will develop in damp areas where they dine on decaying vegetation. Joe Boggs said that one bedeviled caller reported her neighbor had installed a new irrigation system this spring, and they seemed to be testing the system's water delivery capacity. The irrigated lawn, along with areas in surrounding lawns, were almost constantly waterlogged. Dave Shetlar noted that no-see-ums are often a problem on or near irrigated golf courses.
The midges do not fly far from their breeding ground. Intense attacks are often reduced simply by moving a short distance away from wet areas. Consequently, the occurrence of biting midges can be reduced through better water management. The flies will also be discouraged from landing and biting by most proven insect repellents. If all else fails ... RUN!
|
|
OHIO DEPARTMENT OF AGRICULTURE'S (ODA) GYPSY MOTH COOPERATIVE SUPPRESSION PROGRAM SURVEY APPLICATION ONLINE
Although the munching of the leaves has stopped and it is relatively quite in the world of gypsy moths, now is the time to apply to the ODA to be considered for the 2006 Gypsy Moth Cooperative Suppression Program. Applications are available on their website at http://www.ohioagriculture.gov/gypsymoth/, by emailing the program at gyspymoth@mail.agri.state.oh.us, or by calling Plant Industry Division - (614) 728-6400.
A Landowner Cost Share is associated with this program to offset the cost of administering this aerial spray project. The cost to the property owner(s) is 50% of the cost per acre incurred by ODA for the suppression project in total. If, after the treatment area has been assessed and it qualifies for the suppression treatment program, an invoice will be sent.
Following are treatment block qualifications for the state suppression program:
* Be located in a quarantined county.
* Be no less than 50 contiguous acres.
* Have a tree canopy that covers no less than 50 % of the block.
* Consist of at least 35% tree species either susceptible or resistant to gypsy moth.
* Have an egg mass count of at least 250 egg masses per acre for residential forested areas or 1000 egg masses per acre for uninhabited forested areas.
* Receive a favorable assessment from the Ohio Department of Natural Resources and the United States Fish and Wildlife Service.
* If the block qualifies for treatment, an invoice shall be sent to the landowners showing the total
Don't wait until the caterpillars are feeding next spring and summer. Take a walk around and look for their egg masses now. Scout now to avoid the potential for an unpleasant surprise next May.
|
|
DISEASE DIGEST
|
PLANTS GOING SOUTH
Nancy Taylor reported receiving a HOSTA sample that was diagnosed as having a case of SOUTHERN BLIGHT, caused by the fungus Sclerotium rolfsii. Dave Dyke reported that he had submitted landscape bed samples of LANTANA and CALIBRACHOA 'MILLION BELLS' to the CWEPPDC. The plants submitted to the clinic either had entire stems that had turned brown and then died or the entire plant was dead. Nancy diagnosed those plants as being infected with SOUTHERN STEM ROT (aka SOUTHERN STEM AND ROOT ROT), which is also caused by Sclerotium rolfsii.
Sclerotium rolfsii attacks over 200 varieties of plants, including many annuals, tomatoes, beans, peas, and peanuts. The disease is characterized by the development of a whitish fungal growth around the base of herbaceous plants (and a few woody plants ) at the ground line. Small seed-like structures (sclerotia) are found with the fungal growth. They are white at first and later turn dark brown to black. Plants wilt and die suddenly after the fungus girdles the stem.
The fungus develops rapidly during hot weather when temperatures are over 85F. It grows on living and non-living organic matter and becomes most severe when dead leaves or other types of organic matter are present around the base of the plant. This allows the fungus to build up momentum by utilizing energy from the decaying organic matter, rapidly killing the host plant. The fungus develops quickly when summer rains occur after a drought. This stimulates germination of the sclerotia (seed-like structures) and furnishes needed moisture for fungal growth. If the fungus finds ample organic matter and host plants, a large supply of sclerotia are produced for next year. These structures have a hard thick covering that resists weathering.
S. rolfsii grows readily on mulch materials. A grower may want to consider a "mulch free zone" in an area where the disease has been active. Among the fungicide materials labeled for S. rolfsii and outdoor bedding plants are azoxystrobin (e.g. Heritage), which is not specifically labeled for lantana or calibrachoa; flutolanil (e.g. Prostar 70WP), which is not specifically labeled for landscape planting beds but does have a nursery label; and pentachloronitrobenzene (e.g. Terraclor), which is labeled for use in landscape beds. If the diseased plants and their roots, plus any pathogen-contaminated mulch and/or soil are unable to be removed, suppression of Southern stem rot requires a multi-pronged approach involving both cultural and chemical treatments.
A good discussion on this disease and the pathogen, as well as suggestions for the cultural controls that are important in the overall suppression of this pathogen, is found at www.extension.iastate.edu/Publications/SUL8.pdf.
|
|
TURF TIPS
|
MORE TURF TROUBLES
Turfgrass has been challenged by several different insects, diseases and environmental conditions. Patches of dead brown grass having been reported throughout much of the 2005 growing season as a result. Now Dave Shetlar reports that two additional turf pests, JAPANESE BEETLE (Popillia japonica) and BLACK TURFGRASS ATEANIUS WHITE GRUBS (Ateanius spretulus), are well into their development and may cause additional patches of turf to be destroyed.
While checking on turf pest development in research plots, Dave discovered many Japanese beetle white grubs were already in the second instar of their 3 instar development. As these white grubs develop, they may tunnel laterally, feeding on organic matter and fresh roots as they grow. Left undetected and untreated they clip off enough roots of turf that it becomes so loose that it can be rolled up like a carpet. To add insult to injury, as these white grubs continue to grow into the third instar, they could be discovered by raccoons and skunks that dig up vast areas of turf in search of the tender little morsels to be eaten.
Black turfgrass ataenius (BTA) grubs have also been found in abundance in some areas. BTA grubs are known to feed on the roots of annual bluegrass, bentgrass and Kentucky bluegrass. BTA tends to be most common on golf courses, but can also be found in home lawns where damage is uncommon. BTA in Ohio has two generations and currently and currently they are in the middle of the second generation.
Damage from the first generation on BTA would have been seen in mid-June to mid-July as irregular patches of wilted turf that could have been attributed to dry spots as a result of drought. Under continued grub feeding and summer heat, the turfgrass will die; death occurs in mid- to late August and early September.
Effective chemical control of white grubs at this time of year depends on getting the insecticide down to the root zone where the grubs are feeding. This is best accomplished by applying 1/2 - 3/4" of water immediately after application. Repeat irrigation every four or five days to continue moving the insecticide into the soil. This also keeps the crown and root area moist to encourage recovery of the turf. If conditions have been very hot and dry and grubs are deeper in the soil, a pretreatment irrigation of 1/2" applied 48 hours before the insecticide application should encourage grubs to move closer to the soil surface and enhance the level of white grub control. For a list of effective materials and control timing consult OSU Extension Bulletin L-187, "Management of Turfgrass Pests" found at [ http://ohioline.osu.edu/l187/index.html ].
|
|
INDUSTRY INSIGHT
|
GIANT HOGWEED INCLUDED ON OHIO'S NOXIOUS WEED LIST
ODA officials have received reports of giant hogweed in northeast Ohio and warns citizens of its ability to cause bodily harm. The plant, listed on the departments noxious weed list, can be dangerous to humans and should be reported to officials if sighted.
Giant hogweed is one of 17 plants listed on the departments noxious weed list, which includes poison hemlock, wild carrot, apple of Peru, Canada thistle, and others. Researchers have noted these weeds have devastating effects, with the potential to cause major economic impact on crops when spread. Noxious weeds on the list tend to be perennial and generally cannot be selectively controlled.
If discovered, plants on the departments noxious weed list should be reported to local governing bodies township, city, or county officials. Giant hogweed, which is part of a national regulatory program, also should be reported to the U.S. Department of Agricultures Animal and Plant Health Inspection Service (APHIS). Citizens should review USDAs giant hogweed brochure, [ www.aphis.usda.gov/lpa/pubs/poster_phhogweed.pdf ]for verification before reporting sightings to John Burch, 614.834.4625, or the Ohio Department of Agriculture, 1.800.282.1955.
For a copy of Ohios noxious weed list or for USDAs giant hogweed factsheet, go to [ www.ohioagriculture.gov. ]
|
|
VIOLATION OF OHIO'S PLANTS AND NURSERY STOCK LAW SERVES AS A REMINDER
A northwest Ohio court recently found a local man guilty of violating Ohios plants and nursery stock law and was ordered to pay a $250 fine and $111 in court costs. An investigation by the ODA found a Toledo man who had landscaped and moved trees for hire in the area of Sylvania without a license.
Under Ohio law, nursery dealers must obtain a license, which allows the department to conduct regular inspections to assure consumers receive plants that have been labeled properly and are free of harmful insects and diseases. If you would like learn more check out the ODA's website at: http://www.ohioagriculture.gov/plant/plnt-regulations.stm.
|
|
COMING ATTRACTIONS
|
41st OHIO PLANT DIAGNOSTIC WORKSHOP
OSU Extension, Hancock County and the OSU ENLTT, with teachers Nancy Kronberg, Joe Boggs, and Jim Chatfield announce the next Ohio Plant Diagnostic Workshop, on Wednesday, September 14 in Findlay. The location is The Lodge at Riverbend in Findlay. For a registration form on this program of the latest in diagnostic issues and problems, contact Nancy at (419) 422-3851 or (kronberg.3@osu.edu).or just send $30 per person to OSU Extension, 7868 C.R. 140, Suite B, Findlay, Oh 45840. The program starts at 9:45a.m. and runs until approximately 4:00p.m. Rumors are that in addition to a "marvelous lunch" there will be a good deal of screaming by all. The 2nd Annual Hancock County Master Gardener Ice Cream Feast will be included!
|
|
OSU/ONLA NURSERY & LANDSCAPE FIELD DAY
Put this date on your calendar. Dont miss this outstanding event at the Waterman Farm/Wittmeyer Conference Room, OSU, Columbus on Thursday, September 22. More information will be forthcoming in future BYGLs
|
|
BYGLOSOPHY
|
"Gardening requires a lot of water - most of it in the form of perspiration." Lou Erickson
|
|
