If you receive the NCSU Pest News you already learned about ocellate gall midge. However, I found a new infestation this week that showed different developmental
stages so I though I would share the pictures. You can see light green circles on leaves in which the larvae is just developing, darker circles with red edges that have larvae inside. Then there are darker ones that have emergence holes int he bottom. The ocellate gall midge, Acericecis ocellaris causes an ocellate (single-spotted), pale green to yellow, often bright red-margined gall. Galls are 5 to 6 mm in diameter and occur primarily on foliage of red maples but also A. saccharinum,
A. spicatum, and A. pennsylvanicum. I found galls this week on trees in central Georgia so if you have not seen the here yet you will soon. Galls typically appear in May and contain a single, translucent midge larva. Larvae exit the gall and drop to the ground to overwinter as pupae. These are actually quite attractive critters that could even improve the appearance of trees. Just think, if someone bred a tree with yellow and red eye-shaped dots it would be all the rage. That said, these midges usually only occur a few at a time and will not harm tree health. Find out more about maple pests in a free e-book: http://ecoipm.com/extension/extension-resources/
Adult yellownecked caterpillars, Datana minstra, occur in June or July and lay eggs on deciduous shrubs and trees. They will feed on many fruit and ornamental trees including birch, elm, oak, maple, Prunus spp., and others. They feed gregariously in late summer. They consume entire leaves except large mid-veins and can rapidly defoliate trees or cause significant damage. I found the caterpillars pictured below in the forest on a bush I couldn’t identify because every leaf was gone. Scouting for small caterpillars can help reduce damage and improve control if it is needed. Caterpillar management information is available here: http://www.ces.ncsu.edu/depts/ent/notes/O&T/shrubs/note07/note07.html
See pictures of this and other caterpillars on my blog here: http://ecoipm.com/
Emerald ash borer has not yet been found in North Carolina. However, it is found in Tennessee and Virginia so it is just a matter of time before it arrives here or in your home state. The reason I bring it up now is that it is peak adult activity (based on degree day estimates) so they may be more noticeable now than other times of year. Adults will be emerging from D-shaped holes in ash trees. If you notice ash trees that seem to be in decline look for these exit holes and frass around the base of the tree. Early detection of emerald ash borer is critical in trying to reduce the economic impact and protect trees. The most comprehensive and up-to-date information on emerald ash borer can be found at http://www.emeraldashborer.info/
In Raleigh, NC we have reached 900 degree days. This is around the time when Japanese maple scale drawer abundance will be peaking. At least for the first generation. Unfortunately the crawlers have been emerging for a couple weeks and will continue for a couple more. Thus, trying to target all the crawlers with a single insecticide application is tough. However, some help can be provided with systemic neonicotinoids such as dinotefuran and translaminar insect growth regulators such as pyriproxifen. Good publications from University of Maryland and University of Tennessee have nice pictures and diagnostic characters. This has been an increasingly important pest so it is worth looking out for. For other landscape and nursery pest updates visit http://ecoipm.com/ or follow @OrnaPests on Twitter.
By: Amy Fulcher, University of Tennessee Dept. of Plant Sciences
Integrated Pest Management (IPM) can be defined as a sustainable approach to managing pests that combines biological, cultural and chemical tools in a way that minimizes economic, health and environmental risks (Adkins and Sidebottom 2000). The goal of IPM in the nursery is not to eradicate every pest, but rather to manage serious pests to a level that reduces damage and also reduces the cost of pest control. Every insect, disease and weed pest is not a threat to plant health, plant sale or achieving a premium price. Weighing the cost of the damage and the cost of control measures for each pest, as well as the effectiveness of the control option and the time of application, is a component of IPM (EPA).
The main components of a nursery IPM program include prevention, mapping, scouting, record keeping, pest identification, action/economic thresholds, selecting the appropriate control and evaluating the control measure. Once control is deemed necessary, cultural, biological and mechanical techniques as well conventional pesticides are options. The least toxic pesticides are considered before resorting to more toxic alternatives.
To view the entire publication, visit:
REYNOLDSBURG, Ohio (Mar. 26, 2012)—The Ohio Department of Agriculture (ODA) today
announced the discovery of boxwood blight at the Red Mill Farm of Losely Nursery in Lake
County in northeast Ohio. Boxwood blight is a disease caused by a fungus (Cylindrocladium
pseudonaviculatum) that threatens the health and sustainability of boxwood plants. This is the
first detection of boxwood blight in Ohio.
Boxwood blight was first detected in the United States in North Carolina in October 2011. Plant
pathologists in the United Kingdom first identified the disease in the mid‐1990’s. It is unclear
how the disease was introduced into the United States. To date, Ohio is the 10th state to
identify boxwood blight.
The suspect infection was reported to inspectors with the ODA and the Ohio Plant Diagnostic
Network (OPDN) who then sent samples to the United States Department of Agriculture –
Animal Plant Health Inspection Service (USDA APHIS) for confirmation. Officials at this time are
unsure how the disease was introduced into the Red Mill Farm. ODA inspectors have issued a
restriction on all boxwood plants located at the Red Mill Farm and will be conducting further
“Although it is unfortunate to have confirmation on the farm, all known infected plants have
been destroyed and we are working with the Ohio Department of Agriculture to prevent any
further spread of boxwood blight” said Andrew Harding, Vice President and General Manager
of Herman Losely and Son, Inc.
This disease is spread primarily by water (rain splash, irrigation, runoff, etc.), by the movement
of plant material in the trade, and through contaminated tools, vehicles, boots, etc. Initial
symptoms of the disease on boxwood plants include leaf spots and blights, rapid defoliation,
distinctive black cankers on stems, and severe dieback. Most boxwood plants are not killed by
the disease, but will become so defoliated as to be aesthetically unacceptable.
From: Dan Suiter and the UGA CAES Megacopta Working Group
Re: Kudzu Bug Update
Many of you are likely inundated with calls about the invasive kudzu bug. They have now been reported in 126 Georgia counties. Only the coastal, extreme southern, southeastern and northwestern counties in the state are kudzu bug free at this time. If you reside in an infested county, you are likely seeing very high activity of the adult bugs. In light of this activity and our ever-changing knowledge of this pest, we felt that an update was needed.
The kudzu bug is causing a number of problems in its new home in Georgia and the southeastern U.S. It is a nuisance pest to people, a concern for home gardeners, an economic pest of soybeans, and has caused interruption of international trade with our exports to Latin America.
As a nuisance pest, we see a bi-modal pattern of adult activity and nuisance for homeowners and outdoor activities. We are currently experiencing activity of adult bugs as they are emerging from their winter time inactivity that began last October/November. These adults are in search of host plants and, in Georgia and throughout the Southeast, that means kudzu. As the spring progresses and, more importantly, as the kudzu continues to grow, the bugs will become less troublesome for homeowners as they move onto kudzu to feed and reproduce. As this happens, we’ll see fewer and fewer numbers on our homes and vehicles and in our landscapes. They will not disappear from the environment, however, but the nuisance factor will subside as we enter late spring and summer.
We now know that these adults that are active in the springtime will feed and reproduce primarily in kudzu, starting a new generation or cycle of the insect. Unfortunately, many of the adults produced in this new generation move over onto soybeans in June and July where they become an economic problem. During the summer months, reports from frustrated homeowners will likely subside, as the insects feed on their preferred host plants, i.e., kudzu and soybean. However, you may receive complaints from soybean growers or from home gardeners who plant various types of beans in backyard gardens and beans being grown organically for sale.
In most of Georgia, we see these insects developing a second generation during the summer growing season, and in the fall we see the second peak in adult and nuisance activity for homeowners and outdoor activities. What we think happens (based on what we know about other insects) is that a combination of day length, change in plant (kudzu) physiology, dying host plants, and perhaps declining temperatures trigger kudzu bugs to leave their kudzu host in search of protected sites where they will spend the winter. Overwintering sites are any crack or crevice where a group of bugs can aggregate. For example, this can be, but is not limited to, the gaps under the bark of trees or under the siding of a home. They seem to like high places as well, such as the edges of homes (fascia boards, gutters). At any rate, during each of the past several years, this fall flight began in mid-October and did not subside until late November or early December.
Kudzu bugs are attracted to light-colored surfaces, especially white (e.g., siding of homes, white shirts, white cars, etc.). When large numbers of bugs are present, it is not uncommon to find them on most types of vegetation, including oak and pine trees, tomato plants, azaleas, etc. They are not reproducing on these plants. Kudzu bugs only reproduce on plants known as legumes, i.e, what you might think of as anything that grows a bean (yes, kudzu has beans). In the fall, kudzu bugs fly to homes and are a general nuisance due to their large numbers. On homes they aggregate in large numbers. During cool, fall mornings they are not very active, but when temperatures warm into the afternoon their flying and nuisance activity increases dramatically. Those planning outdoor activities should take this observation into account and, if needed, plan outdoor activities for the morning.
Some Bullet Points from the March 2012 Scientific Symposium on Megacopta cribraria held at the Entomological Society Meeting in Little Rock:
Control of Nuisance Kudzu Bugs in the Urban and Suburban Home Environment. Contact Dr. Dan Suiter (email@example.com) in Griffin. When calls are received, as a standard procedure print and send (or direct callers to) the circular “Megacopta cribraria as a Nuisance Pest”, circular #991 at http://www.caes.uga.edu/Publications/pubDetail.cfm?pk_id=7891. Or just give them the website and they can print the circular themselves. Bottom line: vacuum bugs on the inside if they enter; in late summer (in preparation for the fall flight) seal all cracks and crevices around homes and make sure window screens are repaired and that door sweeps are installed; if possible, remove kudzu in summer; outdoors, when bugs get on the building spray them directly with a pyrethroid insecticide (do not spray indoors, however, or anywhere close to a body of water). Prior to the use of any pesticide, first read and follow the pesticide label’s directions for use on the product’s label.
Control of Kudzu Bugs in Soybean. Contact Dr. Phillip Roberts (firstname.lastname@example.org) in Tifton.
Control in Kudzu Bugs in Backyard Vegetable Gardens (including organically-grown beans). Contact Dr. Stormy Sparks (email@example.com) in Tifton.
This brief update authored March 16, 2012 by Dan Suiter with the help and support of a number of scientists and specialists on the UGA CAES Megacopta working group.
The University of Georgia College of Agricultural and Environmental Sciences © 2012-2019. All Rights Reserved.
The University of Georgia is an Equal Opportunity, Affirmative Action, Veteran, Disability Institution.