New ambrosia beetle marching across the US

Nursery growers have been struggling with ambrosia beetles for decades. In the southeast it is

Scopes-eye view of camphore shot borer fresh from a trap mixed in with granulate and other ambrosia beetle species. Photo: Andrew Ernst, NCSU.

Scopes-eye view of camphore shot borer fresh from a trap mixed in with granulate and other ambrosia beetle species. Photo: Andrew Ernst, NCSU.

primarily the granulate ambrosia beetle, Xylosandrus crassiusculus. In the Northeast and Midwest the predominate species is Xylosandrus germanus. These are tiny beetles that make tiny albeit lethal holes in trees. 

In the past several years a new species has been detected in several states including Florida, Tennessee, North Carolina, and just last month Virginia. This is the camphor shot borer, Cnestus (used to be Xylosandrus) mutilatus, and it is BIG. At least by ambrosia beetle standards this one makes holes as big as a pencil instead of then tiny 2mm holes made by other species. You can find out all about it in a thorough publication from University of Tennessee.  

We trap at 5 -10 nurseries every year around Johnston County, North Carolina. In 2011-2013 we captured 1 or 2 camphor shot borers each year. This year we captured about a dozen from at least 3 different nurseries. So it is here to stay and will probably become more of a problem over time. 

Camphor shot borer in a twig photographed by Matt Bertone, NCSU.

Camphor shot borer in a twig photographed by Matt Bertone, NCSU.

SAVE THE DATE: LARVAE EXPECTED

This guest blog post is from four of our amazing undergraduate (or just-graduated!) Frank Lab Summer Employees: Nicole Bissonette (Zoology ‘15), Laura Daly (Horticulture ‘14), Karly Dugan (Animal Science ‘15) and Danielle Schmidt (Zoology ‘15). This blog is proof that even non-entomology majors can fall madly in love with bugs.

The expectant MOTHers in the Frank Lab.

The expectant MOTHers in the Frank Lab.

Once upon a lunch break, the four of us discovered a moth frantically flapping its wings beneath a

Rescued imperial moth

Rescued imperial moth

Southern Magnolia, unable to fly. We were concerned as she struggled to crawl up the tree and decided to bring her back to the Frank lab. Since our fellow coworkers were out in the field conducting research, we had to put on our entomology caps. After some intense googling, we discovered our lovely, large friend was an Imperial Moth.

 Going off our immensely extravagant base of insect knowledge (#sarcasm, #non-entomology majors), our observations lead us to believe that she was pregnant, not relieving herself as we had originally thought. Once brought into the lab, we noticed she stopped laying eggs, since she was probably getting cold due to the air conditioning. So, we relocated her to the balcony outside in the sun. Once warm, her ovipositor picked up speed, and was dropping eggs like ‘dey were hawt.’ We

Imperial moth eggs.

Imperial moth eggs.

decided to let her lay eggs all night in this plastic container as per suggestions on several other blogs. When we came into the lab the next morning, she had laid over 50 eggs! We have decided we are going to raise them as our own and document our experience. Save the date, cross your fingers, and check back for updates on our “MOTHerhood” duties!

 

 

 

 

 

Science Cafe Tonight: Urban ants clean up the food we drop

Our Research Associate Elsa Youngsteadt will host a Science Cafe tonight titled “Urban Ants and What They Do For You” at the North Carolina Museum of Natural Science, Nature Research Center. Elsa and many members of the Frank and Dunn labs spent a ton of time and effort collecting data in NY on the effects of Hurricane Sandy on urban arthropods. In this presentation she will discuss this work in relation to how urban ants help clean up all the crumbs that fall from our mouths as we walk, eat, and talk on the phone at the same time. Turns out ants provide a great service by cleaning up food waste in cities. The Science Cafe starts at 7pm so come early for dinner and beers.

Heres a synopsis of Elsa’s talk. Cities are designed for people, not animals. But some creatures, from pavement ants to house sparrows, enjoy the urban lifestyle, too. As cities grow and invest in parks and gardens, we need to know how these features affect our animal neighbors. Does the design of green spaces shape how animals use them—and whether they use them in ways that we find helpful? In this Science Café, NC State entomologist Elsa Youngsteadt will share her research on ants and other insects in New York City. Find out what happens when you drop a bite of hot dog from your food-truck lunch in a park or a traffic island, and see how urban insects fared during the catastrophic flooding of Hurricane Sandy.

This research was funded by an NSF grant #1318655 “Consequences of extreme weather events for urban arthropod communities: Effects of Hurricane Sandy on ecosystem processes and the spread of exotic species in New York City

Sawdust from banded ash clearwing larvae

I just got some great pictures from one of great Extension Agents, Mark Danieley, this week

Sawdust accumulated around the base of an infested ash tree. Photo: Mark Danieley

Sawdust accumulated around the base of an infested ash tree. Photo: Mark Danieley

of some pretty messed up ash trees in a parking lot. They have sawdust (frass) accumulated on the ground around their trunks and in clumps on the bark. Of course the first thought was whether the tree was infested with emerald ash borer. Mark noted however that the holes were round not D-shaped. Turns out the trees are infested with banded ash clearwing larvae. As the larvae feed they periodically shove frass  out of their galleries to keep them clear. This time of year the larvae are getting very big and thus feeding heavily. Adults will emerge soon. Thus, the holes in the pictures are from last year when adults emerged front he same trees. That is why they did not have characteristic pupal casings sticking out of the holes.

Sawdust in clumps and round exit holes on tree bark. Photo: Mark Danieley

Sawdust in clumps and round exit holes on tree bark. Photo: Mark Danieley

Sycamore lace bugs cause yellow leaves

This week I have gotten three samples from the clinic with sycamore lace bug, Corythucha

Adult sycamore lace bug. Photo: SD Frank

Adult sycamore lace bug. Photo: SD Frank

ciliata. I had just taken some pictures of these beautiful critters last week when I was in Asheville. They really do a number on sycamore leaves and this time of year heavily infested sycamores look pretty bad. The other lace bugs that are important landscape pests are the azalea lace bug and hawthorn lace bug. Like these, the sycamore lace bug causes stippling damage by piercing the underside of leaves with its stylet and sucking out the fluids. Large yellow and gray areas develop on the top of the leaves. In some cases, most leaves on a tree can be entirely covered in stippling damage.

 

Yellow blotch of stippling damage caused by sycamore lace bugs. Photo: SD Frank

Yellow blotch of stippling damage caused by sycamore lace bugs. Photo: SD Frank

Sycamore lace bugs are a native insect. They overwinter as adults under bark or in other sheltered spots and become active soon after bud break. They lay eggs in leaves and complete their lifecycle in around 30 days. However, research from China, where this is an invasive pest, shows that at high temperatures this happens much faster, even twice as fast. This suggests that it could be more abundant in hot urban areas where sycamores are often planted in parking lots and along roads. Our research shows that lecanium scales and gloomy scales become much more abundant on hot urban trees than cooler trees nearby. My anecdotal observation is that this hold true for sycamore lace bugs too. Sycamores are wetland trees and probably are not very happy in hot, sunny, dry spots but lace bugs clearly are.

Sycamore lace bug nymphs. Photo: SD Frank

Sycamore lace bug nymphs. Photo: SD Frank

Management of sycamore lace bugs will be similar as for other lace bugs but you are typically dealing with large trees instead of small azalea bushes or cotoneaster. Thus systemic insecticides applied as a drench can be a good option. Applications of horticultural oil should also help keep abundance low just by killing adults and nymphs that are present.

Thrips vs. Mites: an Epic Fight

This is a guest blog by Post-Doctoral Researcher Sarah Jandricic, who specializes in Greenhouse Entomology. You can read more about our greenhouse research program here.

The fight is about to begin! In one corner of the ring we have the number one pest of greenhouse crops in the world: the western flower thrips.

Western flower thrips and damage on petunia leaf. Photo: SD Frank

Western flower thrips and damage on petunia leaf. Photo: SD Frank

This nasty little insect might look like a lightweight, but it’s in the heavy-weight class when it comes to damage. By sucking out the contents of individual plant cells, thrips cause a scratched, or “silvered” appearance to leaves and flower petals. Adding insult to injury, thrips can also transmit lethal plant viruses like Impatiens Necrotic Spot Virus.

In the other corner, we have the fan favorite – the predatory mite! Cucumeris are notorious for killing and eating 1st instar thrips (the life stage that hatches directly out the egg), and are sold commercially for control of thrips in greenhouses. Adult mites can eat 4 to 10 of these 1st instar thrips each day. But Cucumeris has yet to face its current opponent: the older and larger 2nd instar Western flower thrips.

Ding Ding Ding! The fight has begun!

The video of our fight (Sarah Jandricic and Matt Bertone, NCSU), shows Cucumeris making repeated attacks to the flank of Western flower thrips! But what’s this? The thrips is using its abdomen to land repeated blows to the head and body of Cucumeris! Despite a valiant effort from our plucky predator, it just can’t seem to find an opening. After several rounds, it’s clear that our 2nd instar Western flower thrips has won the fight.

But hold on, folks. Breaking news is coming from the post-fight interview…

It turns out that defending itself from the mite has cost our 2nd instar thrips dearly. Thrips engaging in this sort of battle spend less time feeding, cause less damage to plants, and ultimately are less successful in completing development into adults.

So, the story is clearly not over. The Frank Lab at NCSU is currently investigating ways to capitalize on effects of mite “intimidation” on 2nd instar thrips for better control of this pest in greenhouse crops.

Stay tuned for more updates on this big battle occurring in the tiny world of insects!

 

 

Impatiens Necrotic Spot Virus

In the last month we have had several samples come into the Plant Disease and Insect Clinic with impatiens necrotic spot virus (INSV). These have primarily been greenhouse crops like impatiens and mums but the virus can infect over 200 plant species. It is a lethal virus spread by thrips feeding.  Managing INSV is critical because it can easily over run your crop and cause you long-term problems.  Thrips become infected with the virus while feeding as larvae. After they pupate thrips spread the virus to new plants when they feed as adults.

Robert Wick, University of Massachusetts, Bugwood.org

Robert Wick, University of Massachusetts, Bugwood.org

Thus, INSV management starts with thrips management. You can read more about thrips management in a Insect Note and recent article in GrowerTalks. The essence though is to start with sanitation. Thrips can feed on hundreds of plants so any weeds growing in or near your greenhouse can support thrips feeding and egg laying. Get rid of pet plants and mother plants. Maybe you or you grandmother want to overwinter last years peppers or begonias but don’t. Its not worth it. These can serve as reservoirs for thrips and virus and keep your house constantly infected.

If you have INSV in the greenhouse get rid of all plants that show symptoms and consider get rid of all plants that thrips have fed on. Plants do not immediately show symptoms but they can still infect thrips. So even if you get rid of plants with visible spots thrips may continue to get infected and spread the virus. Get rid of thrips with insecticide applications or ramp up an existing biological control program to get thrips under control. Now is not the time to start a biological control program.

Keep an eye out for tell tale rings and spots on leaves so you can keep ahead of this virus and of course monitor for thrips with sticky cards to keep ahead of them.