New & Free! Southeastern Pest Control Guide for Nursery and Landscape Plants

2017 Southeastern US Pest Control Guide for Nursery Crops and Landscape Plantings.

Tired of going from state to state sifting through extension publications for the latest pest management recommendations? If this sounds like the start of an info-mercial and I guess it is.

A team of University and Extension personnel from around the Southeast has created the 2017 Southeastern US Pest Control Guide for Nursery Crops and Landscape Plantings. Yes its a long title but its a long book available in electronic and pdf versions.

The Guide includes sections on Arthropod, Disease, Weed, and Wildlife control in and around nursery and landscape plants. Comprehensive lists of pesticides are listed in tables to help you find information quickly.

This pest control guide was a project of the Southern Nursery IPM Working Group (SNIPM) and collaborators. Other comprehensive integrated pest management (IPM) manuals for trees and shrubs available for download from the SNIPM web site (also don’t miss the new greenhouse pest iBook). The Southeastern US Pest Control Guide for Nursery Crops and Landscape Plantings was funded by a grant from the Southern IPM Center.

Of course the best part is that its free, available on your device in the field, and will be undated each year. Enjoy.

March 30th, 2017|Categories: Extension, Landscape IPM, Nursery IPM||

Spring and eastern tent caterpillars are a month early

Eastern tent caterpillars in the second week of March 2017. Photo: SDF

Last week I went looking for small new nests in hopes I could find eastern tent caterpillars just as they hatched. What I found were large nests with large caterpillars. March is pretty early for eastern tent caterpillars in Raleigh. This is a result of the warmer than ‘normal’ spring we have had. Based on State Climate Office Growing degree day calculator Raleigh (RDU airport) has accumulated 346 GDD (base 50F) so far in 2017. This is not so different than the 316 GDD accumulated by March 27 in 2016. However, it is almost threes times as many as in 2015 (150 GDD), 2014 (92 GDD), and 2013 (108 GDD).

In 2013 and 2014 we did not reach similar GDD until the third week in April putting us almost a month ahead this year. Interestingly, this matches when Google indicates that most people are looking for information about eastern tent caterpillars. According to Google Trends, ‘eastern tent caterpillar’ as a topic in the Raleigh area has peaked in mid-April (e.g. April 6-12, 2014; April 19-May 9, 2015) each year since 2012. This year we already see a peak March 19-25.

Eastern tent caterpillar

Such large changes in insect phenology is important for many reasons. In some cases phenology of mutualists like pollinators may become unsynchronized. In other cases, predators and prey or parasitoid and host phenology may become unsynchronized leading to loss of biological control. Not many people probably care about eastern tent worm prosperity or that of other pests like cankerworms. However, if these critters hatch before their host plants develop leaves they starve. This means migrating birds and other animals people do care about, and that rely on spring caterpillars for food, also suffer.

Of course monitoring and predicting pest activity is an important part of IPM for caterpillars and other pests. The more pest development varies from year to year, or even from warm to cool spots in a city, the harder IPM becomes. Your state probably has a State Climate Office with a growing degree day calculator. As phenology gets more variable, using these tools rather than relying on previous years to implement IPM tactics will be essential.

March 29th, 2017|Categories: Feature, Landscape IPM|Tags: |

Watch white peach scale – crawlers coming soon

White peach scale (Pseudaulacaspis pentagona) is an armored scale common on many landscape plants and fruit trees. It has a wide host range including over a hundred plant genera such as Buddleia, Camellia, Clematis, Cornus, Euonymus, Hydrangea, Ilex, Ligustrum, Prunus, and many others. The most common host of samples submitted to the PDIC here at NCSU is cherry laurel (Prunus laurocerasus). Cherry laurel is an exotic species which of course is installed in nearly every new landscape I see.

White peach scale females and males on cherry laurel. Photo: SDF

Like most armored scales white peach scales are sexually dimorphic. The females are waxy bumps on twigs but the males grow wings and look like an actual insect. The males emerge from ‘pupal cases’ (not technically pupae). Twigs become covered with the fluffy white pupal cases. This is the easiest time to see and diagnose white peach scale infestations.

Female white peach scale with cover removed surrounded by fluffy white male pupal cases. Photo: SDF

Of course the males come out to mate. Two weeks after the males emerge females will begin producing eggs and crawlers will start hatching. Scouting for the males, even though they do not feed, gives you a head start to plan your management approach.

White peach scales have 3 to 4 generations per year. Infestations are often concentrated on particular branches since scales do not move very far. Dense infestations can kill the individual twigs they are on. Minor infestations in landscapes should be monitored. You can probably inspect most cherry laurels and find some of these. That doesn’t mean you need to treat them; they can just hang out in low densities for years controlled by natural enemies. Plant stress and insecticide applications, like mosquito sprays, could increase the likelihood many armored scale species become problems.

March 7th, 2017|Categories: Landscape IPM|Tags: , |

Early spring flowers=Insecticide risk for bees

Barberry is very attractive to bees and is blooming early in Raleigh. Photo: SDF

Spring in Raleigh is almost a month ahead of usual (is usual a thing anymore?). This means we’ve had red maples flowering since mid-January. More importantly they have been visited by bees the whole time. Not just honeybees either. We have been trapping bees in red maples for the past month or so and found honeybees, bumblebees, and smaller Andrena spp.

Today I noticed hollies flowering along with redbuds, barberry, and azaleas. Surely boxwoods, nandinas, cherry laurels, and other species attractive to bees are not far behind (or is it ahead?). This time of year folks making preventive insecticide applications may not usually think about bees and whether plants are flowering. Many insecticide labels restrict applications when bees or flowers are present.

Hollies have small flowers that many people don’t notice but bees love them. Photo: SDF

Neonicotinoids, like imidacloprid, have been in the news but label restrictions to protect bees are common on most insecticides including other landscape and nursery favorites like bifenthrin and orthene. To be safe: read the labels, don’t make applications when bees or flowers are present, and delay systemic insecticide applications until after flowering. A recent HRI publication and new bulletin and article from Michigan State University could help.

March 1st, 2017|Categories: Landscape IPM, Pollinators|Tags: |

New Bee BMP Summary from HRI

Photo: SD Frank

The Horticultural Research Institute just released a pdf summarizing some BMPs for protecting pollinators from insecticides in greenhouse and nursery production and in landscapes. The crux of it is read the label and follow some basic IPM practices like using alternative management tactics. However, there is also good advice like do not drench ‘bee attractive’ plants with clothianidin, dinotefuran, imidacloprid, or thiamethoxam. And, avoid spraying plants with these products within 3 weeks of shipping. Find other information in a previous post highlighting resources from Michigan State and on the ecoipm Native Pollinator Site.

January 27th, 2017|Categories: Landscape IPM, Pollinators||

Highlights of the 20th Ornamental Workshop

Frank Hale and Andrew Loyd in costume (not mandatory btw) during the Wednesday night social. Photo: Suzanne Wainwright-Evans.

Frank Hale and Andrew Loyd in costume (not mandatory btw) during the Wednesday night social. Photo: Suzanne Wainwright-Evans.

Now over 40 years old, the Ornamental Workshop convened for three beautiful days in late October. One hundred and twenty-three university researchers, extension personnel and representatives from agrochemical companies, biological control companies, tree care companies, public gardens, and others all converged in Hendersonville, NC to geek-out on the pests and diseases of ornamental plants.

Engaged participants soaking up knowledge.

Engaged participants soaking up knowledge. Photo: Suzanne Wainwright-Evans.

Our keynote speakers, Adam Dale (University of Florida) and Steve Oak (USDA FS), started big with presentations about how climate change and urbanization affect insect and disease biology and management. For the next 3 days we had talks and workshops on everything from the latest research on exotic pests like emerald ash borer, crape myrtle bark scale, sudden oak death, and rose rosette, to new innovations in extension delivery. We covered nurseries, greenhouses, chemical control, biological control, new pests, old pests, you name it. We even had a workshop on macrophotography by Matt Bertone (NCSU). You can view the whole program to see what you missed.

Participants Cliff Sadof, Brian Kunkel, Gerald Adams, and Carlos Quesada 'networking' on a hike.

Participants Cliff Sadof, Brian Kunkel, Gerald Adams, and Carlos Quesada ‘networking’ on a hike. Photo: Suzanne Wainwright-Evans.

Of course we never work too hard at the Ornamental Workshop even though ‘work’ is in the name. Each night we gather for drinks and snacks for networking (there is that ‘work’ again) and catching up with friends. The highlight for some folks is Wednesday when we take the afternoon off for a mushroom foray and hiking. This naturally inspires some to attend the social Wednesday evening dressed as their favorite insect or disease. This without a costume can decorate a moonpie to honor their favorite pests.

Moonpie insects and diseases ready to be judged. Photo: Suzanne Wainwright-Evans

Moonpie insects and diseases ready to be judged. Photo: Suzanne Wainwright-Evans

I personally thank all the participants and sponsors for another great workshop. If you want to attend in 2018 watch the website, Facebook page, or join the listserv. If you know someone who should attend this meeting please pass along this post.

Morning at the Ornamental Workshop. Photo: SD Frank.

Morning at the Ornamental Workshop. Photo: SD Frank.

November 9th, 2016|Categories: Landscape IPM, Nursery IPM|Tags: |

Crape myrtle bark scale: New tree pest has arrived in NC

A couple years ago I began warning about a new pest that was spreading throughout crape myrtle country. Now, the crape myrtle bark scale has arrived. From the severity of the infestation it looks like it actually arrived many years ago but now it is “official.” This is bad news because crape myrtles are one of our most commonly planted trees in yards and along streets. Crape myrtles are typically almost maintenance free (unless you top them) but now they will require pest management to stay healthy and beautiful.

Crape myrtle bark scale. SD Frank

Crape myrtle bark scale. SD Frank

Female scales produce fluffy white filaments that cover their body. In spring they produce eggs beneath their body then die. Tiny crawlers hatch from the eggs, settle in their new spot, and begin producing white filaments. They have at least 2 overlapping generations. At low density, crape myrtle bark scale feeds in rough areas around branch collars but as the population increases all the bark may be covered. These scales are most often noticed because trees become covered in black sooty mold. At first many people assume this is from crape myrtle aphids so the scales may go undetected. If you notice unusually heavy honeydew and sooty mold on crape myrtles take a closer look at the bark.

Crape myrtle bark scale is a felt scale related to azalea bark scale and oak eriococcin scale. They feed on phloem like other “soft scales”, thus the honeydew. Even though there is not a lot of efficacy data available drench applications of neonicotinoids are typically effective against phloem feeders. However, since crape myrtles flower continually and attract a slew of pollinators be sure to read the labels for restrictions on using them. Insect growth regulators such as pyriproxyfen and buprofezin are effective for many other scales and may be a good option. Horticultural oil, especially the heavier dormant rate, can reduce scale abundance also.

Crape myrtle bark scale on a rough branch collar. SD Frank

Crape myrtle bark scale on a rough branch collar. SD Frank

There are many subdivisions and streets in North Carolina lined with crape myrtles. Inspect these trees to determine when they become infested. Also consider diversifying the tree planting of your neighborhood. Luckily this pest does not kill trees outright like some other exotic pests increasing tree diversity helps ensure all the trees are not infested or killed at once by a single pest.

August 8th, 2016|Categories: Landscape IPM|Tags: , |

Impervious surface cover is bad for trees. How much is too much?


Gloomy scales on red maple. Photo: AG Dale

We have studied the effects of urban warming and other factors on tree pests and tree health for several years. The gist of it is impervious surfaces increase plant stress by warming the atmosphere and reducing water availability. Adam Dale and Elsa Youngsteadt studied the effects of impervious surface cover on red maples to determine how much is too much? In a new paper they answer this question to create an impervious surface threshold that planners and planters can use to determine if sites are suitable for red maples. Their analyses of impervious surface cover and red maple condition in Raleigh, NC indicate that red maple condition is most likely to be excellent or good if impervious surface cover is less that 32% within a 25m radius. At 33% to 66% impervious surface cover, trees were most likely to be in fair condition. Above 66% impervious surface cover, trees were mostly in poor condition.


Good to know but how do you measure impervious surface cover? Not many landscapers are going to pull up satelite images on their phones and bust out ArcGIS to measure the amount of impervious surface around a tree. Instead we came up with the Pace to Plant technique. With this technique anyone can acurrately measure impervious surface cover at 25 m radius just by pacing transects and counting the steps that fall on impervious surfaces.


With an impervious surface threshold in hand hopefully landscape architects and other planners will not specify red maples on plans when impervious surface cover is high. Tree care professionals on the ground will also be able to assess if a planting site is suitable for red maples. Two small (even medium) steps for urban tree IPM.

May 17th, 2016|Categories: Landscape IPM, Urban Ecology|Tags: , , , |

Dates set for 2016 Ornamental Workshop on Diseases and Insects at Kanuga

Everyone’s favorite biennial workshop on insects and diseases of ornamentals is scheduled for October 24-27, 2016 at Kanuga Conference Center in Hendersonville, NC.

Workshop title and discipline-specific schedules are still TBD, but go ahead and bookmark the new workshop website,, and stay tuned for updates as the time draws nearer.


Spoils of a 2014 fungal foray. Photo: Annemarie Nagle

November 23rd, 2015|Categories: Landscape IPM|Tags: , |

Ambrosia beetle attacks on landscape trees

Frass toothpicks and sawdust collected in the crotch of a crape myrtle tree. Photo: SD Frank

Frass toothpicks and sawdust collected in the crotch of a crape myrtle tree. Photo: SD Frank

Granulate ambrosia beetles are primary pests of nurseries in spring. However, it seems like every year folks report ambrosia beetle attacks on landscape trees in late summer. It is usually not clear if these are granulate ambrosia beetles but there are dozens of related species that do similar looking damage. In this case I found a row of crape myrtles that all had dozens of holes and the tell-tale frass toothpicks. These four crape myrtles were planted between the sidewalk and street but so are many of the 17,000 crape myrtles in Raleigh. So why these four? Why not the dogwoods planted a few feet away? Dogwoods are very suseptible to ambrosia beetles. Who knows? In any case it is not clear what will happen to these trees. Generally trees attacked by ambrosia beetles die because 1) they are full of holes and 2) the ambrosia fungus interferes with vascular transport. I will watch these trees for the next year or two to find out. In general though this is not a reason to spray all the trees in a landscape. Ambrosia beetles target stressed trees and home in on them very specifically.

September 3rd, 2015|Categories: Landscape IPM|Tags: |