Slide 4 - EAB, why do we care?: So let s start with why emerald ash borer is so important, why do we care about it?

Transcription

1 Module 1 Narration Slide1 - Title: This program will discuss emerald ash borer and its potential impacts on the logging industry. The first part of this program will be presented by Jeff Hahn, an extension entomologist with the Dept. of Entomology on the St. Paul campus of the University of Minnesota. Slide 2 - How to use Adobe Presenter: Before we continue, please take a look at how to use Adobe Presenter. The button on the bottom of the screen on the left starts and stops the narration for each slide you are on. The buttons to the right of this allow to advance forward or backward if there is a slide you wish to view other than the one you are looking at. The button all the way over on the right allows you to adjust the sound. Click on the icon to make a bar appear. Move the volume control button to adust how loud or soft you would like the narration, then click anywhere on the screen to make the bar disappear. Slide 3 - Learning Objectives: We have several learning objectives today. We will learn to identify emerald ash borer and to recognize the common signs and symptoms of infested trees. We will examine its life cycle and discuss its implications for moving ash material. We will look at Minnesota s strategy for minimizing risk and impact of emerald ash borer as well as compare ash recommendations in other states. We will construct a case study of ash in Michigan for emerald ash borer. We will identify ash management recommendations and considerations in Minnesota and finally describe and discuss the current emerald ash borer quarantines. Slide 4 - EAB, why do we care?: So let s start with why emerald ash borer is so important, why do we care about it? Slide 5 - Impacts: Emerald ash borer is an insect that attacks all native North American ash species. In Minnesota, that is black, green, and white ash. It does not attack mountain ash because that is Sorbus and not a Fraxinus. Not only are all ash species susceptible but none have shown any resistance to EAB. Size doesn t matter as trees as small as ½ inch diameter are attack all the way up to the largest ash trees. Emerald ash borer is closely related to some native borers, like bronze birch borer and twolined chestnut borer. If you are familiar with these insects, you know they only successfully attack stressed, declining trees. Similarly emerald ash borer prefers stressed, unhealthy ash. Slide 6 - Impacts: However, it can also successfully attack healthy ash trees as well. This insect has already killed 10 s of millions of ash trees in the U.S., most of them occurring in Michigan. Minnesota has a lot too lose as it has one of the highest concentrations of ash in the U.S. with well over 900 million ash trees present. We have the highest concentration of black ash in the country in a north woods. So, we have a borer that

2 attacks all species of ash, all sizes of ash and in all states of health with very limited control options. No ash in Minnesota is safe from emerald ash borer. Slide 7 - Native range of EAB: Emerald ash borer originally comes from Asia. The natural range of EAB is northern China, Russia, Japan, and Korea. It is probably found in Mongolia although there are no official records of its presence there. Slide 8 - EAB in Asia: Interestingly, emerald ash borer is not a pest in Asia. In fact there was very little known about EAB when it was first in the U.S. In addition to ash, it also attacks elm and walnut in China. Its ability to attack other tree in North America has been very closely researched and it is only known to attack ash here. Slide 9 - In how many states have EAB been found? Here is a question to think about. You haven t had this answer yet, so it give it your best guess. In how many states has EAB been found? Click the circle of the answer you believe is right and then click the submit button. Slide 10 - EAB in North America: EAB was first found in North America in SE Michigan in It was estimated to have been already been present between 5 to 10 years before its discovery. It most likely was introduced into the U.S. in ash wood used for crates or in wood stabilizing cargo in ships. As of September 1, 2010, emerald ash borer has been found in 15 states with infestations being found for the first time in Iowa and Tennessee in Emerald ash borer is also found the Canadian provinces of Ontario and Quebec. Slide 11 - EAB first found in St. Paul, MN: Emerald ash borer was first found in Minnesota in May, 2009 in St. Paul, near the St. Paul campus of the University of Minnesota. It was first discovered by the technician of a local tree care company as he was doing some routine work. He had found some woodpecker activity and upon looking more closely discovered a larva that looked like an emerald ash borer. He contacted the MN Dept. of Agriculture to report this find. MDA came out and collected some samples. By the next day there was confirmation from the USDA. Interestingly, analysis of the wood later indicates the infestation to be about three years old which is relatively young infestation. This is significant because other states have typically found that infestation when first found have been there for at least 4 5 years Slide 12 - Where is EAB?: Emerald ash borer is only found in two sites in Minnesota as of the summer of The first is in the St. Paul Minneapolis area. Slide 13 - Where is EAB?: The known infestations are confined to a small area north of I-94 and around highway 280. So far it has not bee found outside this area within the Twin Cities.

3 Slide 14 - EAB in Houston Co.: It is also found in Houston county in the southeast corner of Minnesota. Emerald ash borer was found in 2009 in Victory, Wisconsin just across the Mississippi river but was not confirmed in Minnesota that year, although it was very likely already present. It was finally confirmed in spring, Slide 15 - EAB life cycle: The life cycle of emerald ash borer is very similar to closely related species that are native to Minnesota such as bronze birch borer and twolined chestnut borer. Adults first start to emerge sometime during spring and can be active for about a month. Slide 16 - Map of first emergence: This map shows when EAB would be expected to first start to emerge. When this would happen would depend on where you live and what kind of spring you are having. This map is based on degree day temperatures, i.e. an accumulation of temperature required by EAB before it is able to finish development and exit trees. In Minnesota, first emergence could begin any time from late May in southern Minnesota to mid to late June in NE Minnesota. If we have a warm, early spring, first emergence would be expected to occur sooner and conversely would be delayed if we have a late spring. Slide 17 - EAB life cycle: Once the adults emerge, they feed on ash leaves, mate, then lay eggs in cracks in the bark. They typically attack the top of the tree first. Larvae hatch and bore under the bark in to the phloem where they tunnel for the summer. By fall they create a shallow chamber where they remain for the winter. They pupate the following spring, completely the life cycle. It usually take one year for emerald ash borer to finish their life cycle, although sometimes it can take two years. Slide 18 - How does EAB kill trees?: Remember, the larvae attack the phloem layer which transports the carbohydrates, the tree s food, from the leaves to the roots. As this layer becomes girdled the tree eventually starves and dies. One or two emerald ash borers is not going to kill a tree but when 100 s or 1000 s infest an ash, they will seriously injure and kill it. Slide 19 - How does EAB kill trees?: Depending on the size and the health of a tree, it can take anywhere from 1 5 years year for emerald ash borers to kill a tree with 3 4 years being average. Slide 20 - EAB adult ID: One way to verify that emerald ash borer is present is to find the beetle. Let s take a look at how you identify the adult. Slide 21 - EAB adult ID: Emerald ash borer, a species of metallic wood boring beetle, is a slender beetle about 1/3 ½ inch long. It tapers at the tail end so that is the narrowest part of the insect. What really stands out on this insect is the bright, iridescent green color. If an emerald

4 ash borer lifts its wing covers, you will see the body is a purplish, magenta color. Slide 22 - MN insects that can be confused with EAB: Unfortunately, there are lot of other insects that are green too and can be mistaken for emerald ash borer. Look carefully, especially at the shape of the emerald ash borer to distinguish it from other green insects. One of the most common insects mistaken for emerald ash borer is the sixspotted tiger beetle. You can see how the body narrows behind the head and is a different shape. Another common insect is the polydrusus weevil. It is smaller than an emerald ash borer and the narrowest part of the insect is the head. An insect doesn t even have to be green to mistaken for emerald ash borer. People occasionally think a cicada, probably due to its size, is an emerald ash borer. Any time you can see obvious wings, however, that is not going to be an emerald ash borer. If you ever see an insect and are not clear whether it is an emerald ash borer or not, send the specimen or picture of it to the Minnesota Dept. of Ag for identification Slide 23 - Which of the following is emerald ash bore quiz: Let s try a quiz, which of the following is emerald ash borer. Slide 24 - EAB larva ID: If you are looking under the bark of an ash, you may see an emerald ash borer larva. Let s see how to identify it. Slide 25 - EAB larva ID: The larvae of metallic wood boring beetles, are called flatheaded borers. They are legless, have a flat body with a head embedded into the front of the body so it is not obvious. When you look at an emerald ash borer, it kind of looks like a tape worm with pretty obvious segments. Each of these segment flare out and are bell-like or oar-like. There are a pair of small, pincer-like tails at the tip of the abdomen. An emerald ash borer is whitish and can grow as large as 1 ¼ inches long. Slide 26 - Which of the following is emerald ash borer quiz: Here is another quiz. Which of the following is the larva of an emerald ash borer. Slide 27 - Symptoms: Another way to verify whether emerald ash borer is present is by diagnosing it from symptoms of infested trees. However, it is very difficult to diagnosis emerald ash borer from symptoms, most are not diagnostic Slide 28 - Which tree has EAB?: Perfectly healthy looking ash can actually be infested. A tree on the St. Paul campus that had trapped two EAB on a purple trap was removed. Despite looking healthy, numerous 1 year galleries were discovered. Can you tell which tree is infested? There are not any tell tale signs to make a diagnosis easy.

5 Slide 29 - Which tree has EAB?: It is in fact the tree on the right, although there is no easy way to determine that Slide 30 - Thinning crown: The first symptom of an EAB infested tree is thinning foliage in the top of the canopy with limbs eventually limbs dying back. Unfortunately, there are lot of ash that can look like that. Slide 31 - Which tree has EAB?: To emphasize that point, can you tell which tree has emerald ash borer? You can not rely just on thinning foliage and dead branches to identify it. There are a variety of other factors that can also cause these symptoms in ash. Slide 32 - Which tree has EAB?: It turns out it is the tree on the right that was infested with emerald ash borer however it is essentially impossible to tell at this distance whether it is EAB or not. Slide 33 - EAB exit holes: A symptom that is diagnostic is the exit holes the adult beetles create as they emerge from the trees. Slide 34 - D-shaped exit holes: When the adult beetles emerge, they create exit holes that are about 1/8th inch in size and D-shaped, i.e. flat on one side and round on the other side, The flat side of the D is horizontal, although it varies whether the flat side is down or up. While these exit holes are diagnostic they are hard to detect. Emerald ash borers typically first attack ash in the canopy where they are hard to find. Even when they occur on the trunk, they can still be challenging to see. D-shaped exit holes are created by all related species, including bronze birch borer and twolined chestnut borer. However, these species attack trees other than ash. Slide 35 - Woodpecker feeding: Woodpecker feed on EAB by flaking off bark and feeding on large larvae underneath. While woodpecker feeding is not diagnostic of EAB, it should raise a red flag and encourage you to examine the affected tree more closely. Slide 36 - Bark cracking: Bark can crack when old galleries develop callus tissue causing the bark to split. Although bark could crack for other reasons, look for larval galleries underneath which would be diagnostic for EAB. We do not see bark cracking due to the activity of native borers in ash. Slide 37 - Larval feeding galleries: The best way to verify emerald ash borer is by the galleries. Note the distinctive S- shape the create as they tunnel under the bark. These galleries are in green ash.

6 Slide 38 - Larval feeding galleries: Here is are emerald ash borer galleries in a black ash. Note how the S is much broader, possibly the result of thinner phloem. Slide 39 - Larval feeding galleries: When a lot of galleries occur, it can be more difficult to see individual S-shaped galleries as they overlap. However, when a tree is this infested, the D-shaped exit holes should be apparent. Slide 40 - Native ash borers: There are a number of native borers that can be found in ash so just because you find an insect does not make it emerald ash borer. The shape of an emerald ash borer should be distinctive that you can distinguish between it and the larvae of native borers. Slide 41 - Native ash borers: Native borers also make differently shaped exit holes and galleries. Exit holes are usually round or oval, never D-shaped. Galleries might be fan shaped or meandering tunnels but not S-shaped. Slide 42 - Agrilus borers attack many tree types: If the damage fits EAB, make sure the material is ash as there are many related species native to Minnesota that attack a wide variety of other trees Slide 43 - What are we doing about EAB?: So what are we doing about emerald ash borer? We can summarize the action into three categories, Preventing it, Detecting it, and Managing it. We will talk about each of these in more detail. Slide 44 - Quarantined counties in Minnesota: When we talk about preventing emerald ash borer we are generally talking about quarantines. A quarantine restricts the movement of ash material out of and through designated counties. Angie will talk about this in more detail later but at this point I would like to point out that as of summer of 2010, there are only three counties under quarantine, Ramsey and Hennepin counties in the Twin Cities area and Houston county in the southeast corner of the state. This will change as more infestations are found in the future. Slide 45 - Firewood cartoon: One of the strongest messages we tell the public is don t move firewood. Firewood is the main route that allows EAB to be moved large distances. Buy and burn firewood locally and don t bring it home with you. Slide 46 - Early detection: It is important to detect emerald ash borer as early as possible. This can be done in several ways. First, we have many programs to educate the public. The Minnesota Dept of Agriculture has the Arrest the Pest Hotline where people can contact them if

7 they believe the have seen emerald ash borer. Some of these people may be put into contact with a First Detector, a group of volunteers that help to triage the calls that come in of suspected emerald ash borers. Slide 47 - Trapping: The Minnesota Dept of Agriculture has an active detection program to try to locate emerald ash borer. Unfortunately this beetle is very challenging to detect and the traps that are available are only so-so in effectiveness. The primary trap being used now are the purple traps. This trap is a three sided piece of corrugated plastic covered with a nontoxic glue and baited with chemical attractants. Unfortunately a pheromone has not been discovered yet, like we have for gypsy moth and Japanese beetle, which would dramatically increase trap effectiveness. Trap trees have been commonly used. A trap tree is one that is deliberately girdled, making it more attractive. Then trap trees are then cut down during fall and debarked to look for galleries, D-shaped exit holes, larvae or pupae. Trap trees are probably the most effective for detecting low levels of emerald ash borers. However, it is a labor intensive activity and there is no longer resources for its continued use. MDA will also survey declining trees, cutting them down and inspecting for evidence for emerald ash borer. These traps are a good opportunity to further educate the public on emerald ash borer. There are signs attached to each tree that is being used for trapping to explain what they are for and how to report emerald ash borer if they think they see it. Slide 48 - EAB population growth vs. tree mortality: This graph illustrates the relationship between emerald ash borer populations and tree mortality. Notice at first, emerald ash borer numbers are slow to increase and there is little to no tree mortality. However, there gets to be point where emerald ash borer numbers dramatically increase. There is a lag of about two years and then ash tree mortality starts to significantly increase. In nearly all states, the first detection of emerald ash borer occured after it has been in the state 4 6 years which is about when populations start dramatically increasing with death of lots of ash not to far behind them. In Minnesota, we are fortunate as we discovered emerald ash borer when it had only been in the state for about three years. By finding EAB early, we can take steps to slow it down. Slide 49 - Slowing EAB down: When we are talking about management, we are not talking about eradication. That was tried in Michigan and it failed. However, we are trying to slow emerald ash borer down. There are several strategies for doing this. First we can slow it down by removing and destroying infested trees so the beetles are not able to emerge and spread. You can also draw emerald ash borers in the area to ash that are deliberately girdled, much like a trap tree. By fall, you remove and destroy the trees and any emerald ash borers in them. Insecticides are effective and trees can

8 be treated which will kill emerald ash borers that attack them. You can also preemptively remove ash, especially ones that are declining or otherwise are undesirable. You would not even necessarily need to cut a lot of ash to significantly reduce emerald ash borer. Removing just a few large trees could represent a significant amount of food for emerald ash borers thus limiting their ability to reproduce. Slide 50 - Insecticide options: Insecticides are available to protect ash in the urban landscape. The most common products are systemic and can either be drenched or injected into the soil, injected into trunks or sprayed on bark. Some products are available to homeowners to use themselves while others are for use by commercial applicators. Slide 51 - Managing EAB: Again, we can not eradicate emerald ash borer but there is value in reducing their spread. You can see in this chart that when nothing is done, emerald ash borers move throughout Minnesota four times as fast compared to when we take steps to slow it down. There are advantages to slowing down emerald ash borer. The longer we can keep their populations below a certain level, the longer we can hold off significant ash death and the longer we can spread out our resources as we transition to non-ash trees. Slide 52 - What if you believe you have found EAB?: You can telephone or MDA to report EAB. Slide 53 - For more information: For more information, you can go to the University of Minnesota Extension, Minnesota Dept. of Agriculture, or the Dept. of Natural Resources s EAB web pages. Slide 54 - Module 1 completed: This completes module 1. Click on Click Here to continue to module 2, EAB and Forest Management, presented by Angie Gupta, an Extension Educator in Natural Resource Management, located at the Rochester Regional Extension Office.