 Hi everyone, my name is Caitlin Kessheimer and I'm an Extension Entomologist with Auburn University and Alabama Cooperative Extension Service. To help with giving a brief overview of insects that attack industrial hemp, many of you are aware that this is the first year that industrial hemp can legally be grown in Alabama thanks to the 2018 Farm Bill. That classifies it as an ordinary agricultural commodity. And a few states outside Alabama have been growing hemp since 2015 or so with the passage of the 2014 Farm Bill, but prior to that hemp has not really been grown in any major capacity since World War II. However, lots has changed in the past 70 years and now that we're back to growing industrial hemp again, there is much to be learned. So today I'm going to give a quick background on hemp and so far what we learned this first year about pest management in Alabama. So when I talk about industrial hemp, I'm talking about the plant cannabis sativa. The genus cannabis includes multiple species that produce these unique compounds that are not found in any other plants that we know of so far. And cannabis can be broadly separated into two distinct groups and these include marijuana and industrial hemp. Now we all know that marijuana is illegal to grow in Alabama, but while these two groups, marijuana and industrial hemp, are used for two very different purposes, they are impossible to distinguish from each other visually and they will interbreed out in the wild. So talking about marijuana, that is bred and grown for THC content, which is a psychoactive compound. These plants are almost exclusively grown indoors in greenhouses and cultivated for that THC content. On the other hand, we have industrial hemp and the major difference here is the low THC content is less than .3% THC. And industrial hemp can be grown indoors similar to marijuana, but it's also grown outdoors like when you think of a typical row crop shown in this picture here. It's bred and grown for a variety of end uses, including fiber, seed, and cannabidiol, which is used as medicinal compounds, also known as CBD. So I mentioned there's a lot of different end uses. It's a very versatile plant and it can be grown for seed and fiber production. Seed can be used for human consumption and it's similar to growing small grains in the field. Hemp grown for fiber can be used for a variety of things such as clothing, paper, rope, or building materials. And that's one of the reasons it was so popular about 100 years ago. And then hemp grown for fiber and seed are usually grown from seed in the field and have a much higher plant density in the field than those grown for CBD. And so plants grown for CBD is really the majority of the plants grown in Alabama right now. These are much lower density plantings in the field and are typically started as trans plants shown here in the greenhouse and then moved into the field. And these are primary female plants, which are the desirable plants as opposed to the male plants that are also created. And there's also a lot of variation just in the way that hemp is grown. It's a very new crop. There's no real kind of standard protocol for growing yet as we're still kind of figuring things out. It's grown outdoors in the field on plastic, pots, high tunnels, greenhouses, so there's lots of variation with it. And with that variation of growing methods, indoors and outdoors comes a lot of pests. These weeds and diseases and insects aren't really going to wait for us to figure out the agronomics of the crops before they show up. So here we are and we have to kind of figure it out as we go along. For the next few minutes, I'm going to focus primarily on insects, but I do just want to mention that as you're growing, it's really important to have a solid integrated pest management program that should be in place for any type of pest, especially with hemp because we know very little about it and you're going to get inundated with weeds and diseases and insects. Many of these can hinder the production of your crop. A lot of the questions this year have focused on pesticide usage and what can we spray to kill the weeds, to stop this disease from spreading, to kill this insect. But there are several other things that are part of a good IPM strategy that you can do before you want to even think about spraying that will really help your crop. And so when it comes to pest management, there's all these different strategies. People usually think about pesticides or chemical control as their first line of defense. But really as shown in this triangle here, it should be your last resort. It should be the last thing you consider because there's a variety of strategies and if you employ all these strategies and create a healthy crop, if you have a healthy plant, it is more resistant to these pests and diseases. It's able to fight off more of these problems and can maybe sustain some damage that isn't going to be economical. And so starting with cultural and sanitation, cultural control, sanitation, keeping your plants healthy, starting with good, clean seed, starting with a good, good, clean soil, clean field, making that environment less hospitable for pests, making sure you're not going into a field that's already filled with weeds or filled with pests that are overwintered and have just a leg up on your crop. Another often overlooked method is mechanical control. Just getting out there, scouting for your pests and hand removing those insects, creating physical barriers, sticky traps are really good if you're growing indoors in the greenhouse. And then thinking about what are our free options for biological control? What are our natural enemies that are going to be out there that can help reduce some of the pest populations? And so I mentioned pesticide should be your last resort. If you end up spraying your hemp, it should be used as a sensible control option and, most importantly, in accordance with label directions. The label is the law and so you have to make sure to follow that label. And so I realized, as we're in this first year, there's a lot of confusion, a lot of misinformation about there about what we can use in terms of chemicals on hemp. And so just a few things to think about before you put any chemical on your hemp. The number one thing to know is all pesticides used on hemp have to be registered with the Alabama Department of Agriculture and Industries. It's the responsibility of the producer to make sure that the pesticide can be used legally. And so this goes back to reading the label because that label is the law. And additionally, we have these rules that are put in place by the state of Alabama. But then if you're going to take your hemp to a processor or buyer, they may have a separate set of regulations. And so I implore you before implying any chemical to give your processor or your buyer a call to make sure that they will still accept the product after the chemical has been applied. Having this information beforehand is crucial to ensure that you will pass because a lot of these processors have lists of chemicals that they will and will not accept. They'll also do residue tests for a lot of different substances and give the product a pass or fail. And so you want to make sure that if you put all this time and money into growing the crop that it's going to pass. And finally, be very cautious of any lists that are not released by the Alabama Department of Ag or Alabama Cooperative Extension. These have not been approved by the Department of Ag in the state of Alabama. There's some other lists going around that are approved by other states. And if you apply a product that is on another state's list but is not registered with the Department of Ag in Alabama, it will result in your crop being destroyed. If you have any questions or are confused about this, feel free to give me a call. My contact information will be at the end of this or call the Alabama Department of Ag to verify the acceptability of this chemical. Okay, now I'm just going to briefly go through what we have seen as some of the major economical pests so far that are likely going to be major problems moving forward with industrial hemp. This is not a comprehensive list and it will likely change. I mentioned this is the first year and so things may be very different a year from now, but I imagine that these will continue to be a problem. And so the first one is fire ants. These have been a major pest of hemp across the entire state of Alabama, whether it's grown in open field conditions, in plastic, in pots, in high tunnels, etc. What they'll do is they'll build mounds near the base of the plant underneath the pots, underneath the plastic. And then they'll tunnel into the stem, as you can see in some of the pictures here, chewing and killing the seedlings, especially really young plants are very vulnerable. And then after they kill a plant, they will quickly move to nearby plants. And then in many cases, it's been so dry that you don't see those stereotypical fire mounds that you're used to seeing because the ants get so deep into the ground because it's so hot. And so the picture on the bottom left here shows the yellowing and wilting of a plant from ant damage. And you can see some of the tunneling and stripping of the bark that they've been doing in fields this year. So recently we put out a pest alert about some of the products that were approved through the Department of Ag for fire ant control. These are all contact insecticides, which means they have to find the fire ant mound and apply the chemical on the mound to kill the ants. There is one bait in there, and that's extinguished professional. And the bait means you put out the food, the ants go get it, and they bring it back to the nest and feed it to all the workers and the queen. The bait will obviously be the most effective for long-term control. But before applying, again, check with your processor before to make sure that they allow it, even though this one has been approved by the Department of Ag. And just one thing, when using these products, especially the oils and the pyrethrins, these are all natural products, and they'll break down with UV exposure. And so you want to make sure you're not applying them in full sun. Also, fire ants, they don't want to be out in the heat of the day. They're not going to be foraging. They're not going to be at the top of their mounds. They're going to be deep down in the deep part of the ground when it's really hot in their tunnels. And so the best time to apply these mound treatments is first thing in the morning before it gets too hot or late in the day when it cools off. The other thing to think about is these do need a lot of water to get into their extensive tunneling system. So don't cut back on water when you're applying some of these products. Our fire ant pest alert can be found at the URL at the bottom of this slide. The next major pest that's going to be causing economic damage both indoors and outdoors are the hemp russet mites. And these are a special type of mites that's very, very small. And what we know so far, these are a specialist on cannabis plants. And so they're only going to be found on hemp or marijuana. When you're getting plants or scouting for them, I would highly recommend investing in a hand lens or a magnifying glass if you have one. Because you won't see these mites without magnification because they are so tiny on the plants unless you're looking for them. But you will see their characteristic damage. So these pictures show characteristic hemp russet mites damage with this upward curling of the leaves, yellowing brittle leaves that can break off. And you can tell these are different from spider mites if you're familiar with spider mite damage because hemp mites do not produce the characteristic webbing that spider mites do. However, they are similar to other mites in that they are very prolific and they can explode in populations if left unchecked. So you can see in this picture, it's really bad mite damage. There's thousands if not millions of mites on these plants and the buds are already starting to turn brown. So hemp mites can also infest the flower tops and feed on the pistols, which will render the female flower sterile. In the picture on the left, you can see the pistol is healthy and white or green and hasn't been damaged by mites. To contrast, the pistol on the right is turning brown from a severe mite infestation. Unfortunately, we don't have a lot of information on the life history of hemp mites. Since they're a specialist on cannabis, like I mentioned, there just hasn't been a lot of research done on them. For plants grown outdoors, they may overwinter on infested seeds. For indoor plants, they can remain on plants year round. Anyone who's grown plants in a greenhouse or inside knows just how difficult it is and how much a pain in the butt mites are. And as the mite population increases and starts to kill the plant, they will crawl to the top of the plant to be dispersed naturally by wind or water. And this is why early control and sanitation are so important. If you are receiving transplants from a greenhouse, this is where you need to get out your hand lens and inspect your plants very carefully. This is likely one of the main sources of hemp mites as they're moving around through the state. In terms of control, we don't know a lot about biological control agents yet. That isn't to say some generalist predators won't work. We just don't know what they are yet. We have some data on what won't work. But this is a very specific unique type of mite, and it behaves differently than other mites that we have more experience with. And so it's going to take a lot of time and research just to figure out what are the best biological control agents. And there is some information about using oils, like horticultural oils, and they are effective against some russet mites, like tomato russet mites, but they may or may not be effective against the hemp russet mites. Again, we just don't have this research, and so the best option is to scout your plants regularly and inspect anything coming from an indoor growing situation because that's really where you can have year-round mite infestations. And finally, there's a whole host of caterpillars that are known to infest hemp and that we've already started to see around the state of Alabama. Historically, European corn borer was the most destructive, but that really hasn't materialized yet, but that's not to say it isn't a problem or won't be in the future. There are defoliating caterpillars that we don't think is going to cause a lot of problems, a lot of economical damage as they chew the leaves. There's also a hemp borer that hasn't shown up yet in Alabama. It may be here. I just haven't found it personally. One of the main problems we're dealing with right now at the end of the season, it's mid-September right now, are the bud feeders, and these are feeding on the buds of the more mature hemp plants. Both causing economic yield loss and then opening that bud up to infection, which can cause bud rot, which will also lead to more yield loss. One of the other more abundant caterpillars we've seen is the yellow striped armyworm. Corn earworm is also really common. In a lot of instances, proximity to other crops has determined both the abundance and severity of damage by some of these pests. Look at your landscape and see what's around you. Is there a lot of corn nearby? Use that to gauge what the threat might be in terms of the caterpillar pests. The point of this slide is just to show that there's a lot of different species of caterpillars that may feed on hemp at any given growth stage. And so it's vulnerable to attack, and we're still trying to figure out what is going to be the most damaging. But right now, it looks like these bud feeders are having the biggest impact in terms of economic yield loss. So what can you do? The best thing really is just to be out there scouting your crops to control the caterpillars early. You'll likely see the feeding damage or frass, which is insect poop, before you see the worms, because they're really small. They can be cryptic. They might hide under the leaves in the heat of the day. And sometimes even giving the lack of chemical control options that we have right now, hand removal may be your best option. But keep in mind that as we get into these later growth stages of these caterpillars, they become increasingly difficult to kill. Bigger caterpillars do more damage. They feed more, and they're harder to kill. Even if we had all the chemical options available, a lot of them don't even touch these late instar, fourth, fifth instar caterpillars. And so the best thing you can do is find them when they're really young, when they're only a quarter inch or smaller at most. And so you really need to be out there inspecting your crop to make sure that you don't have these caterpillars. And so I mentioned it a minute ago, but one of the biggest problems we're seeing right now is with corn earworm. They're still around. The corn either has been harvested or even some of the late planted corn is past that silking stage. And so the corn earworm moths do not want to lay eggs in the more mature corn. And so the most attractive crop to them right now is all the hemp that's around. The hemp has these beautiful flowers, and it's just really attractive for these moths to lay eggs for them to hatch and have these nice buds for them to feed on. And once that bud gets a wound from caterpillar feeding, it now becomes vulnerable to infection from pathogens. This is where we're seeing a lot of bud rot in the last couple of weeks with this more mature hemp. So looking ahead, we are seeing some pests that are causing economic damage. Fire ants, mites, caterpillars, namely yellow-striped armyworm and corn earworm. But there's a lot of information gaps. We don't know what the relationship between these insects and yield loss is quite yet. And as a result, we haven't developed economic thresholds. Just because we have some insects on the plant doesn't necessarily mean it's a problem. It doesn't mean it's going to lead to economic yield loss. But hopefully some of these questions we can answer moving forward. We expect very much so in 2020 and in coming years. There will be an increase in the acreage of hemp grown in Alabama and other states. And this will likely lead to an increase in the number and diversity of insects, weeds, and diseases that can move into the crop. And so it's important just to stay vigilant. In 2019, we had approximately 10,000 acres approved for growing hemp in Alabama. And I imagine that will go much higher in 2020. And so just stay on top of your scouting and proper identification of any pests we see in the field. And I understand that we have a lot of legal uncertainties regarding pesticide usage between the state and federal government. The USDA is hopefully getting ready to release some rules in the coming weeks. And so hopefully that will add some clarity to this issue with pesticide usage. But if you have any questions or are confused about what product to use, if you can use it, please get in touch with me. Please get in touch with someone from the Alabama Cooperative Extension Hemp Action Team. We are happy to answer your questions. We'd much rather answer your questions than you apply something you can't and then have to deal with your crop being destroyed. But right now, we just have more questions than we do answers. And so as a researcher, this is great. But there's just a lot of information gaps that we need to fill moving forward. I hope this was helpful. Here's my contact information. Please don't hesitate to get in touch with me. And hopefully we can get your questions on industrial hemp answered moving forward. Thanks.