Marketing Abroad

Considering Marketing abroad to folk in other countries?  Then you might find this program useful:

http://www.susta.org/services/outreach_events_Asheville13.html

The event is on July 16th here in Asheville NC.

For more information contact your local Cooperative Extension Center and ask for the Commercial Horticulture Agent.

Pest News for Week of June 3rd

ORNAMENTALS AND TURF

From: Steve Frank, Extension Entomologist

Hawthorn and Azalea Lacebugs

Azalea and hawthorn lacebugs started hatching last week. Now we see a mix of adults and nymphs. Hawthorn lacebugs feed on pyracantha, serviceberry, and cotoneaster. Azalea lacebugs feed primarily on azaleas. Both cause stippling damage visible on the top of leaves and leave fecal spots on the bottom of leaves. For more information on lacebug management, see Ornamental and Turf Insect Information ENT/ort-39 at http://www.ces.ncsu.edu/depts/ent/notes/O&T/shrubs/ort039e/ort039e.htm. Imidacloprid will kill both pests, but should not be used on plants that are flowering or that will flower soon due to negative effects on pollinators.   

(http://www.xerces.org/wp-content/uploads/2012/03/Are-Neonicotinoids-Killing-Bees_Xerces-Society1.pdf).

Woolly Apple Aphids

This week we noticed woolly apple aphid infestations on pyracantha bushes around campus. These aphids produce cottony fluff along the branches. When you brush away the fluff (really it is wax the aphids produce) you will see hundreds of pink or grey aphids crawling around. Woolly apple aphids have been out for a month or so, but are becoming very noticeable now. Infestations for multiple years produce large leafless patches on bushes. The aphids cause galls to form on branches and branches become black from sooty mold. Soap or oil should provide some control. Additional aphid management information: http://www.ces.ncsu.edu/depts/ent/notes/O&T/flowers/note38/note38.html

Flea Beetles

Redheaded flea beetles, Systena frontalis, have become a serious pest of nursery stock over the past several years. They are an especially damaging pest because they feed on roots and leaves. They overwinter as eggs in the soil. Larvae hatch in spring and begin feeding on roots. The larvae are elongate and creamy-white. Heavy infestations may reduce root mass or girdle plants. Adult redheaded flea beetles are small, shiny black, beetles with reddish to dark colored head and long antennae. They are about 1/16 of an inch long and, as the name suggests, jump when they are approached. There are at least two generations in Delaware and may be more in North Carolina.

We found adults and adult feeding damage this week. The favored hosts are Itea, hydrangea, forsythia, and knockout roses. Adult management has been frustrating for growers who find that even frequent insecticide applications do not reduce adult abundance and damage to acceptable levels. Part of this has to do with not controlling larvae since even if you kill all the adults present in a crop (which you won’t) more adults are emerging from the soil every day. Research thus far in Delaware and grower reports indicate that Talstar, Sarfari, and Flagship provide good efficacy as foliar applications, but do not have long residual activity.

Recommendations for the use of chemicals are included in this publication as a convenience to the reader. The use of brand names and any mention or listing of commercial products or services in this publication does not imply endorsement by North Carolina State University, North Carolina A&T State University or North Carolina Cooperative Extension nor discrimination against similar products or services not mentioned. Individuals who use chemicals are responsible for ensuring that the intended use complies with current regulations and conforms to the product label. Be sure to obtain current information about usage regulations and examine a current product label before applying any chemical. For assistance, contact an agent of North Carolina Cooperative Extension.

For more information contact the commercial horticulture agent at your local Cooperative Extension Center.  

Pest Alert for Week of May 27th

ORNAMENTALS AND TURF

From: Steve Frank, Extension Entomologist

Cottony Maple Leaf Scale Eggs

Cottony maple leaf scale is one of several cottony scales in the genus Pulvinaria. You can find these now on their most common hosts: maple and dogwood. Stand under a tree and look up and you will see cottony masses about the size of a cotton swap stuck to the bottom of leaves. These are the egg masses. They each contain many hundred eggs that are hatching as we speak. The crawlers will settle and feed on the leaves all summer then migrate back to branches in fall before leaf-drop.

Cottony Cushion Scale

Cottony cushion scale is an exotic pest that became a very important pest of citrus. However, it is quite generalist and does affect several ornamental plants such as nandina, euonymus, boxwood, rose and others. Cottony cushion scale is very noticeable when female egg sacs are present. They are present now and most of the time there are several overlapping generations per year. Cottony cushion scale is an example of a relatively successful biological control program in the U.S. The vedalia beetle was captured in its homeland of Australia and released to bring the pest under control. Although cottony cushion scale can still be found and remains a pest it is often kept in check by this wide-spread beetle. These are in a different family (Mararodidae) than other soft scales (Coccidae). However, control measures are similar to those outlined in the soft scale management note:

http://www.ces.ncsu.edu/depts/ent/notes/O&T/shrubs/note156/note156.html

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Recommendations for the use of chemicals are included in this publication as a convenience to the reader. The use of brand names and any mention or listing of commercial products or services in this publication does not imply endorsement by North Carolina State University, North Carolina A&T State University or North Carolina Cooperative Extension nor discrimination against similar products or services not mentioned. Individuals who use chemicals are responsible for ensuring that the intended use complies with current regulations and conforms to the product label. Be sure to obtain current information about usage regulations and examine a current product label before applying any chemical. For assistance, contact an agent of North Carolina Cooperative Extension.

For more information contact your local Cooperative Extension Center and ask for the Commercial Horticulture Agent.

Pest News for Week of May 20th.

ORNAMENTALS AND TURF

From: Adam Dale, Graduate Student, and Steve Frank, Extension Entomologist

Painted Maple Aphids

Painted maple aphids are common on maple trees and do not generally require treatment. However, you will probably see them if you are scouting for scales or other more important pests. They are quite colorful up close. We sent out an alert and blog post (http://ecoipm.com) this week with a full life history description and pictures from under a dissecting scope. As with all aphids and other phloem feeders you can see shiny honeydew on leaves below where aphids are feeding. The tree in the picture below also has a severe scale infestation so the honeydew you see was not all from these aphids. 

From: Steve Frank, Extension Entomologist

Ambrosia Beetle Trapping

This week did not find any ambrosia beetles in our traps and did not get any attacks on our experimental trees. So we may be out of the woods for this year. Since this week was cool I will keep trapping one more week to be sure we don’t get surprised by latecomers who were waiting for warm weather. Check the blog or twitter alerts for updates.

Cankerworms Gone!

Cankerworms have finished feeding for the year and are no nestled safely underground as pupae. At this point you should take stock of which trees were defoliated in your yard or on the properties you manage.  Heavily infested trees will also be heavily infested next year because the caterpillars pupate under the tree they were born in then climb back up as adults in fall. Consider banding these trees and adjacent trees to prevent consecutive years of defoliation.

Cankerworm information: http://ecoipm.com/research/cankerworm-project-home/

More banding information: http://www.cabarruscounty.us/government/departments/cooperative-extension/lawn-garden/Pages/Cankerworm-Prevention.aspx

Elm Pests Get Going

Right now a lot is happening on elm trees. For those of you who still have elm trees you can look for elm leaf miner, Fenusa ulmi, and woolly elm aphid, Eriosoma americanum. Elm leaf miner is a sawfly that lays eggs in elm leaves. The larvae mine tissue creating blotchy, brown translucent areas on the leaves. In late spring the larvae exit leaves, drop to the ground and borrow an inch down to pupate.  Affected leaves will remain on the trees and become brown as mined tissue dies. They may drop prematurely. This time of year you can find a few adults left but mostly you will find larvae in various stages of development. Mines are small so far but expand rapidly. Imidacloprid and Orthene can be used to kill larvae in mines, but they are protected from contact insecticides such as bifenthrin. If adults are present in your area, foliar applications of these products can reduce oviposition.

Woolly elm aphids are an interesting aphid that manipulates host foliage to create a shelter. The foliage is not altered into a true gall like those on witch hazel but as you can see in the picture that are pretty snug and protected from the elements. These aphids use serviceberry (Amelanchier spp.) roots as alternate hosts. They overwinter as eggs on elm bark. A female aphid emerges as elm leaves are expanding. She feeds on the underside of a leaf and at maturity produces 200 eggs. The infested leaves begin to curl and accumulate waxy debris that makes the aphids look woolly. Mid-summer a winged generation develops that migrates to Amelanchier trees. These colonies of twisted leaves can be easily pruned out. In the case they are over abundant or there are other pests present an insecticide application may be warranted. 

Lady Beetles

Lady beetles seem particularly abundant this week. On a single bush I found several dozen this morning. There are two stages pictured: larvae and pupae. I figure everyone knows what adults look like. Lady beetles and their larvae feed on many soft-bodied insects such as aphids, mites, scales, caterpillars, and many others. Avoid applying insecticide applications when lady beetles are present. Adult lady beetles typically lay eggs only where there is prey. So if you see lots of lady beetles you may need to take a look at what else is on your plant.

Slugs in the Landscape and Nursery

After a wet couple weeks I have seen a lot of slug damage to annuals and perennials in landscapes. Slugs thrive in moist area such as around dripping water spigots and irrigation heads. With all the rain we have had though they are everywhere that is shady and humid. Management of slugs begins with making the habitat less suitable for them by reducing moisture, decaying vegetation, and debris or pots they can hide under. Of course, reducing pots in not an option at nurseries. There are some baits that can be broadcast in slug prone areas. These include products containing metaldehyde or methiocarb (Mesurol) which are carbamates toxic on contact or ingestion. These products are also toxic to pests and children so baits should be inconspicuous and sprinkled over the area rather than arranged in piles that pests and children will notice. Iron phosphate (Sluggo) also has good efficacy against snails and slugs. It also has less mammalian toxicity. Review the below websites for articles on slugs and slug management:

http://www.oan.org/associations/4440/files/digger/Digger_APR_2011_p49-53.pdf

http://www.ipm.ucdavis.edu/PDF/PESTNOTES/pnsnailsslugs.pdf

New Articles About Nursery and Landscape Pests

We have a new article in Nursery Management on spider mite identification and management and a new article in American Nurseryman about ambrosia beetles and the most current management strategies. These articles and other industry publications are posted on our Industry Publications page:

http://ecoipm.com/extension/extension-resources/industry-publications/

Gloomy Scale Crawlers are Active

Gloomy scale, Melanaspis tenebricosa, is an armored scale that is found on maples and other tree species. It becomes very abundant on landscape maples and can cause branch dieback and tree death in some cases. It is not unusual to find trees with nearly 100% of their trunk covered in scale. Street trees are particularly prone to gloomy scale. I have never found one that didn’t have it! Crawlers of this scale are active now and can be seen on bark and under scale covers. Control of this scale is complicated because crawlers emerge over 6 to 8 weeks so it is impossible to treat all the crawlers at once with horticultural oil or other contact insecticide. This is as opposed to scale such as euonymus scale in which all crawlers are produced within a narrow window of 2 weeks or so. However, horticultural oil can still be applied to kill gloomy scale because it will kill some adults also. We have found even a single application dramatically reduces scale abundance. Several systemic products are available to provide longer control of even late stage scales. These include Safari, TriStar, and Distance though it is important to note that imidacloprid (Merit) is not effective on armored scale. More information on armored scale control can be foundhttp://www.ces.ncsu.edu/depts/ent/notes/O&T/shrubs/note157/note157.html.

To see an overview of gloomy scale on urban trees watch our short video:http://www.youtube.com/watch?v=1Fg-ZPkJwRA&feature=youtu.be

Lecanium Scale Crawlers!

Oak and European fruit lecanium scale are one of the largest soft scales in our area. Scale ovisacs are brown and rounded reaching 6 mm in diameter. This is the most noticeable stage and is present right now. As members of the soft scale family Coccidae, lecanium scales produce honeydew that can cause sooty mold on oaks or plants below. Oak lecanium scale primarily infests oaks trees. However, European fruit lecanium can infest many tree species including oaks. They are impossible to tell apart without a microscope (even then it is hard). Large populations can reduce growth and vitality especially in newly planted trees. 

Eggs are present now under adult scale covers and crawlers are beginning to hatch. The crawler stage should be targeted for best efficacy. On trees small enough to treat foliage horticultural oil can be used. On larger trees a systemic such as dinotefuran can be applied as a drench or trunk injection. This scale is not easily eradicated and optimal control measures are still unclear. It is attacked by many parasitoids and predators that can reduce scale abundance if protected from insecticides. A short video by graduate student Emily Meineke describes the scale biology (http://www.youtube.com/watch?v=tD6I7P6BdKU). You can see another video about her research (http://www.youtube.com/watch?v=UnhoEFnNHxo).

For more information contact your local Cooperative Extension Center and ask for the Commercial Horticulture Agent.

Plant Evaluation Symposium

Sustainable Beauty: Landscape Plants That Thrive in the Southeast

Enjoy a full day of ornamental plants selected for their unique flowers, foliage, fall color, bark,  drought tolerance, and adaptability to changing climate conditions. Researchers, plantsmen, and extension faculty from across the South will highlight native and non-native woody and herbaceous plants that will enrich and extend your garden’s seasonal interest.

Garden Centers should invite their customers!

For more information and to access a copy of the brochure click on the following link:  Symposium-Brochure

"The brochure is best viewed using Adobe Acrobat reader.  Some browser plug-ins make the text hard to read with the background, so try Adobe Acrobat if you have trouble viewing it."

To Register on-line simply visit our NCSU Go Links


For more information contact your local Cooperative Extension Center and ask for the Commercial Horticulture Agent.

Flooded Fields and Pest Pressure

After the recent rain fall and the flooding that has occurred many of the trees in your fields will have an increased level of pest pressure particularly from various water molds as well as Granulate Ambrosia Beetle GBA.  It would be a good idea to do extra monitoring for pathogens as well as plan on spraying for the GBA.


For more information contact your local Cooperative Extension Center and ask for the Commercial Horticulture Agent.

Pest Alert for Week of May 5th

ORNAMENTALS AND TURF

 

From: Steve Frank, Extension Entomologist

Midge With An Eye on Maples

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/.

Rose Sawflies

I found these sawflies on knockout roses this week in Georgia. I also found some on my roses in Raleigh that were slightly smaller. They are probably the curled rose sawfly, Allantus cinctus, but I am waiting on a positive identification. In any case you can look for damage to leaves by these and other sawflies. Small larvae typically skeletonize the leaves. Larger larvae consume entire leaves. Scout to this damage and also for feces which are a sure sign of something feeding on your plants. If infestations are large a contact insecticides such as a pyrethroid or acephate can be applied. Conserve is also labeled for sawflies. Small infestations in home landscapes could be managed with horticultural oil or insecticidal soap.

For more information contact your local Cooperative Extension Center and ask for the Commercial Horticulture Agent.

Pest Alert for Week of April 28th

ORNAMENTALS AND TURF PESTS

From: Steve Frank, Extension Entomologist

Ambrosia Beetles Still Active

Just a quick update in case you are not trapping ambrosia beetles. We are still finding a lot of beetles in traps. This week we had 132 attacks on one tree in our experimental nursery. Management of ambrosia beetle (http://www.ces.ncsu.edu/depts/ent/notes/O&T/trees/note111/note111.html) damage requires pyrethroid applications every 3 weeks to the trunks of trees. Ambrosia beetles usually attack below the first scaffold branches so you do not need to spray the canopy. Most folks apply permethrin with an airblast sprayer. We have tested a manual sprayer and fold more complete, even coverage. You can read about it in a recent paper (http://ecoipm.files.wordpress.com/2012/02/franksadof2011reprint.pdf). The manual sprayer has two opposing nozzles to quickly cover tree trunk with insecticide. It takes a little longer but uses less insecticide and reduces drift and secondary mite outbreaks.

It’s Still Aphid Season . . .

Last week I reported on rose aphids covering the buds of a rose vine in my neighborhood. This week I poked around campus and found several more aphid species. The first site was spirea aphids. These aphids were coving the new tips of spirea plants at a park in Cary, North Carolina. The result is distorted foliage if they feed on the growing tips too long.

Last week I found some crape myrtle aphid eggs on a tree that still had leaf buds but no leaves. They were shiny black and tucked beneath slivers of papery bark. This week when I went back to find them I only found shriveled black shells. Several days later I found the first crape myrtle aphids of the year. This coincided with the first full grown leaves. Crape myrtle aphids are specialists and only feed on crape myrtle. They occasionally become abundant but are usually subdued by natural enemies.

Finally I found tulip poplar aphids starting to build up on tulip poplar leaves. I watch these every year. For a couple weeks the aphid density increases then you start to see parasitoid mummies and lady bug eggs. For the rest of the summer they stay under control.

Aphids often become abundant this time of year because they are slightly ahead of their predators and parasitoids. However, soon the natural enemies catch up and keep the aphid populations in check. In many cases having some aphids on the plants around your house is good because it attracts predators and parasitoids that will feed on other more damaging pests.

Protecting Pollinators

This time of year many folks are applying systemic neonicotinoid insecticides to their plants and grass. Research has found that these insecticides move into plant nectar and pollen. Through this route they can negatively affect pollinators and especially bees. I reposted a blog post about protecting pollinators from last year (http://ecoipm.com). This provides more detail and links to a review by the Xerces Society about the effect of neonics on pollinators.

Boxwood Leaf Miners Emerging

Last week I saw a lone boxwood leaf miner adult hovering around a bush on campus. This week I went to look for more. I didn't find adults the day I went out but did find pupal casings sticking out of leaves. This indicates adults recently emerged. The maggots pupate in the leaf blister. As the adult emerges the pupal case get caught on the leaf. This holds the leaf in place so the adult can wriggle out. Boxwoods can be treated with a pyrethroid to prevent flies from landing on the bush to lay eggs but watch out for mite outbreaks. Imidacloprid will kill maggots within the leaves but (based on article above) it is best to apply after flowering.

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Recommendations for the use of chemicals are included in this publication as a convenience to the reader. The use of brand names and any mention or listing of commercial products or services in this publication does not imply endorsement by North Carolina State University, North Carolina A&T State University or North Carolina Cooperative Extension nor discrimination against similar products or services not mentioned. Individuals who use chemicals are responsible for ensuring that the intended use complies with current regulations and conforms to the product label. Be sure to obtain current information about usage regulations and examine a current product label before applying any chemical. For assistance, contact an agent of North Carolina Cooperative Extension.

For more information contact your local Cooperative Extension Center and ask for the Commercial Horticulture Agent.

Pest News Alert for Week of April 21

ORNAMENTALS AND TURF

From: Steve Frank, Extension Entomologist

Rose Aphids

This week I found a lot of aphids on some rose bushes near my house in Raleigh. I have not yet determined whether they are rose aphids, Macrosiphum rosae, but it doesn't matter a lot to folks managing them. This seems early to have such a large population of aphids but there they are. Aphids can be managed with horticultural soaps or oils or with a number of different insecticides in the aphid fact sheet. One of the most common is imidacloprid but research shows that systemic neonicotinoids like imidacloprid can be harmful to pollinators that ingest pollen and nectar. So consider other options before drenching plants with these insecticides.

More information can be found at http://www.ces.ncsu.edu/depts/ent/notes/O&T/flowers/note38/note38.html.

Oak Eriococcin Scale Active

Oak Eriococcin, Acanthococcus quercus, is not very well known. Not much research has gone into understanding its biology or control. It is in the family Eriococcidae which includes several felt scales including Azalea bark scale. This scale is quite common around Raleigh and is very apparent this time of year. As the name implies its primary hosts are oak trees. I find it primarily on willow oaks along streets. The oaks on Hillsborough Street (near North Carolina State University campus) are literally covered top to bottom. The scale produce cottony white egg masses that are often in the crotches of twigs. Very little efficacy data is available but there are reports that imidacloprid and other treatments for soft scale work for these as well. Even horticultural oil may be an effective treatment this time of year right after egg hatch. More information can be found at http://www.ces.ncsu.edu/depts/ent/notes/O&T/shrubs/note156/note156.html.

Cankerworm Update

I have written about cankerworms already, but this year has been bad and I am getting a lot of calls and e-mails about them. At this point, you can expect the cankerworms to hang around for another week or two then disappear. They have defoliated some trees on campus and covered others with dense webbing. Cankerworms do not create webbed nests the way tent caterpillars and webworms do. The webbing is just a tangle of thousands of threads from which the caterpillars dangle. Above are pictures to assist pest managers or Extension agents with calls or complaints so you can see what folks are experiencing.

More information can be found at http://ecoipm.com/research/cankerworm-project-home/.

       

From: Emma Lookabaugh, Plant Disease and Insect Clinic, and Barbara Shew, Extension Plant Pathologist

Be on the Lookout for Cedar Apple Rust

Most of us who live in the triangle are hoping for rains to wash away the yellow film of pollen coating our cars, houses, and sidewalks. Spring rains also jump start the most bizarre life-stage of cedar apple rust, a common disease that affects apple trees (and crab apples) and eastern red cedar trees.

The cedar apple rust pathogen (Gymnosporangium juniperi-virginianae) requires two hosts and four spore stages to complete its complex life cycle. On cedar trees, the most obvious signs of infection are firm brown galls, which are about the size of a golf ball and are usually found scattered on the tree’s branches and twigs. After a heavy rain, the galls produce striking bright orange gelatinous horns, which are composed of millions of spores called teliospores. In dry periods, the horns can be seen as short spikes covering the galls. If you find a gall with dried horns, cut it out of the tree, place it in a glass of water and watch over the next few hours as the horns expand.

The cycle of wetting and drying can continue several times during the spring, and in each cycle the teliospores germinate and give rise to another spore type, called basidiospores. These basidiospores are forcibly discharged into the air and are wind-blown to nearby apple trees.

Apple leaves and fruit are most likely to be infected when they are wet and temperatures range from 46 to 75° F. Yellow to orange spots are produced on the upper surface of the apple leaves one to two weeks after infection. The spots on leaves may be raised or swollen and infected fruit may be slightly distorted. Small black dots within the lesions signal the production of the next spore type, the pycniospores (also called spermatia). One to two months later, fringed cup-shaped structures (aecia) appear on the underside of the apple leaves and these contain aeciospores, yet another spore type.

The aeciospores are windblown to cedar trees in late summer to early fall, where they germinate and infect to produce galls. The galls produce teliospores in the second year after infection, completing the life cycle. G. juniperi-virginianae survives in the gall tissue for only two years. After its second year, the spore producing year, the pathogen dies in the gall tissue. On apples, the pathogen survives only a few months, just long enough to produce the aeciospores that infect cedar trees.

Cedar apple rust causes only minor damage to cedar trees from twig dieback. Damage to apple is more significant and can result severe defoliation and fruit blemishes. Since this pathogen requires both hosts to complete its life cycle, control can be achieved by eliminating one host from the surrounding area, although oftentimes eradication is not feasible or desirable. Additional control measures include the use of disease-resistant apple cultivars, properly timed fungicide applications on apple, and removal of cedar galls before spring rains.

Check out this cool video of telial horns expanding (Video: Arlene Mendoza-Moran):

http://www.youtube.com/watch?v=-lZ_twBLr3Q&feature=player_embedded#t=0s

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Recommendations for the use of chemicals are included in this publication as a convenience to the reader. The use of brand names and any mention or listing of commercial products or services in this publication does not imply endorsement by North Carolina State University, North Carolina A&T State University or North Carolina Cooperative Extension nor discrimination against similar products or services not mentioned. Individuals who use chemicals are responsible for ensuring that the intended use complies with current regulations and conforms to the product label. Be sure to obtain current information about usage regulations and examine a current product label before applying any chemical. For assistance, contact an agent of North Carolina Cooperative Extension.

For more information contact your local Cooperative Extension Center and ask for the Commercial Horticulture Agent.

Pest Alert for Week of April 14

ORNAMENTALS AND TURF

From: Steve Frank, Extension Entomologist

Ambrosia Beetles

Ambrosia beetle activity has been sporadic this year. Remember those two 70-degree days in January? I had reports of ambrosia beetle attacks on those two days. Since then I have had a few other reports of beetles in traps or occasional attacks. At our research nursery, Raleigh, however, we hadn’t captured any until this week. Then Tuesday the traps filled up and two trees were hit. It seems ambrosia beetles are finally out in Raleigh and we had similar reports from the mountains and foothills. 

Ambrosia beetle management starts with reducing plant stress. In particular we have found that trees with too much water are preferentially attacked. It is easy to overwater this time of year when transpiration and evaporation are low. The next step is preventive applications of permethrin. Apply permethrin to tree trunks and try to avoid spraying the canopy. Our research shows that spraying tree canopies results in spider mite outbreaks later in the year (see the paper here:http://ecoipm.files.wordpress.com/2012/02/franksadof2011reprint.pdf). 

Cankerworms Hatching

Cankerworms were very abundant last spring and we predict the same this year. Cankerworms eggs were laid over the winter and just started hatching in Raleigh last week. You can see the tiny caterpillars if you shake branches or just watch for them dangling below trees. They feed on many hardwood tree species but willow oaks seem to be damaged most heavily. We have written a lot on the biology and management of these critters. See a recent article in American Nurseryman (http://ecoipm.files.wordpress.com/2013/03/an_feb13_planthealth.pdf). You can find information and links to other articles on our dedicated Cankerworm Project webpage (http://ecoipm.com/research/cankerworm-project-home/cankerworm-project/). The important thing to remember is that they only feed for 4 to 6 weeks and only have one generation per year. By the time they get big and start defoliating trees they are about to quit and pupate in the soil until fall. The best management tactic is tree banding in the fall when adults are active. This time of year there is not much to do especially for large trees.

Eastern Tent Caterpillars

Eastern tent caterpillars hatched in the past couple weeks and have already established big nests. The easiest way to deal with tent caterpillars is to prune out the nests. Eastern tent caterpillars make nests in the crotch of trees. (Fall webworms make nests at the end of branches.) So it you can’t remove the nest you can poke it with a pole pruner. This destroys the nest so many caterpillars fall to the ground and others get eaten by birds. Opening the nest also lets parasitoids in to kill the caterpillars. For severe infestations there are some insecticide options. Products containing Bacillus thuringiensis (Bt) are effective against caterpillars. Other active ingredients labeled for caterpillar control include spinosad, Beauveria bassiana, acetamiprid, acephate, azadirachtin, and bifenthrin. Keep in mind that these caterpillars spend most of their time in a water-proof nest so contacting them is difficult. This limits the efficacy of many insecticide applications.

Extension Resources Online

We have many extension resources such as factsheets, articles, pest news, and presentations consolidated as links on my website (http://ecoipm.com). In addition, you can visit the site to read my blog or twitter feeds. You can also sign up to follow my pest alert Twitter feed @OrnaPests and my general ecology and IPM twitter feed @ecoIPM via Twitter or by clicking the ‘Follow’ buttons on my website. @Ornapests provides short timely alerts when new pests become active in the field accompanied by pictures and links to management information. I recently posted “pdf” files of about a dozen articles I have written for industry magazines and a new free book on the management of tree pests in nurseries and landscapes (http://ecoipm.com/extension/extension-resources/).

For more information contact your local Cooperative Extension Center and ask for the Commercial Horticulture Agent.