Got Nature? Blog

As you decide best management practices for your woodlands, this short video shares how native grape vine can be a positive addition or a detriment depending on your goals. Lenny Farlee, Purdue Extension forester, shows you what it looks like and how it grows even to the tops of the trees.

If you have any questions regarding trees, forests, wildlife, wood products or other natural resource topics, feel free to contact us by using our Ask an Expert web page.

Resources
A Woodland Management Moment, Playlist, Purdue Extension – Forestry and Natural Resources Youtube Channel
Invasive Species, Playlist
Woodland Stewardship for Landowners, Playlist
Investing in Indiana Woodlands, The Education Store, Purdue Extension resource center
Forest Improvement Handbook, The Education Store
Invasive plants: impact on environment and people, The Education Store
What are invasive species and why should I care?, Got Nature? Blog, Purdue Extension
Woodland Invaders, Got Nature? Blog

Lenny Farlee, Sustaining Hardwood Extension Specialist
Purdue University Department of Forestry and Natural Resources

---

Purdue Landscape Report: Trees provide many benefits for our homes and properties. If a tree is found to have a defect such as dead branches or broken limbs from a storm; it can become a risk issue. It is important to understand that tree owners have a duty to inspect and maintain their trees. All property owners should take reasonable steps to protect themselves by involving a qualified consultant or certified arborist when needed.

All trees have some sort of risk involved with it. They are living organisms that are endangered by environmental impacts and pests. However, it is important to create a balance between the risk a tree may pose and the benefits provided by the tree. We don’t want to remove trees unnecessarily, but rather reduce the liability by Identifying, analyzing and evaluating the problem.

Inspect regularly: Trees should be assessed through inspections by a qualified arborist, preferably an International Society of Arboriculture Certified Arborist. It is especially important to inspect trees after major weather events. At a minimum, trees should be carefully checked out every 3-5 years.

Document and maintain records: Every inspection should be recorded and kept on file for future reference. Past evaluations can show how a tree has changed in its health and structure over the years. Also, these written evaluations could minimize liability if a failure occurs and a claim is filed against the tree owner.

Tree Inspections: For a tree to be considered a risk it must be defective and a target that is threatened.

A target is people, property or activities that could be injured, damaged or disrupted by a tree failure. Review everything in the target zone. This should include the area inside a circle around the tree, which is at least as wide as the total tree height.

Read the body language of the tree. Inspect each section of the tree including the crown, branches and root zone to check for signs of failure. These include:

• Dead, diseased, dying or broken branches.
• Thinning or poor canopy health.
• An unstable branching pattern overextended or weakly attached branches, or cracks in the stems.
• Cracks or decayed areas in the main trunk.
• Exposed or decayed roots, heaving of the soil, fungus growth or cracks in the soil around the root plate.

Among the characteristics to consider when conducting tree risk evaluations are:

• Decay, cankers, cracks and other positive indicators of weakness in the roots, stems and branches.
• Canopy size, shape and weight distribution. This is especially true in situations where a tree is exposed to windy conditions, is leaning or has a poor stem-to-canopy ratio.
• Crown architecture. Poor branching and similar characteristics can create high-risk situations in strong winds and other weather conditions.
• Plant health and vigor. This determines how a tree can overcome wounding or pest infestations.

What do you do when a defect is found?
The goal is to reduce the likelihood of failure. Most of the time pruning can improve risk situations. Perhaps cabling and bracing may be an option. Also, plant health care improves the trees condition which can reduce risk… the last option should be removal and that should be an informed decision.

Recurrent inspections to determine tree health and condition are important for sustainable, long-lived tree plantings. The most important factor for any tree owner is know when to contact an ISA Certified Arborist who understands tree risk assessment. They can help with the decision making for the tree if there are concerns about its safety and health.

For more information refer to Trees and Storms: Understanding Damage, Risk and Recovery from theGot Nature? Blog by Purdue Extension, Department of Forestry and Natural Resources (FNR).

Find a certified arborist in your area by going to Trees are Good.

Resources
Planting Problems: Trees Planted Too Deep, Video, Purdue Extension – Forestry and Natural Resources Youtube Channel
Planting Your Tree Part 1: Choosing Your Tree, Video, Purdue Extension Youtube Channel
Tree Planting Part 2: Planting a Tree, Video, Purdue Extension Youtube Channel
Tree Appraisal and the Value of Trees, The Educational Store, Purdue Extension resource center
Surface Root Syndrome, The Education Store
Iron Chlorosis of Trees and Shrubs, The Education Store
Tree Pruning Essentials, Publication & Video, The Education Store
Cold Injury to Trees, Got Nature? Post, Purdue FNR Extension

Lindsey Purcell, Urban Forest Specialist
Purdue University Department of Forestry and Natural Resources

---

Recently during an online program (video) I received a question about the risk of using toxicants for controlling moles in lawns. Specifically, the question was if animals (pets or wild animals) ate the moles that consumed the bromethalin “worms” or “grubs” would that harm them. I decided to do some digging (no pun intended) for more information so people can make informed decisions regarding their use.

What is bromethalin?
From the Purdue University Animal Disease and Diagnostic Laboratory:
“Bromethalin was developed and released in 1985 to combat a world-wide problem of rodent resistance to warfarin-like anticoagulant rodenticides. Bromethalin is not an anticoagulant but is a highly potent rodenticide that provides a lethal dose to rodents in a single feeding. Death occurs within 24 to 36 hours after ingestion. It is a pale, odorless, crystalline solid compound in the diphenylamine family. Its mechanism of action is to uncouple oxidative phosphorylation in the mitochondria of the central nervous system. This leads to a decreased production of ATP. Low levels of ATP inhibit the activity of the Na/K ATPase and lead to a subsequent buildup of cerebral spinal fluid and vacuolization of myelin. The increased CSF results in high intracranial pressure, causing damage to nerve axons, inhibiting neural transmission and leading to paralysis, convulsions and death. Signs of a sub-lethal dose include hind limb ataxia, depression, extensor rigidity, opisthotonus, lateral recumbency and vomiting. High doses may bring about severe muscle fasciculations, hind limb hyperreflexia, seizures, hyperthermia, depression and death.”

From the Merk Veterinary Manual:
“Bromethalin, a nonanticoagulant, single-dose rodenticide, is a neurotoxin available as bars (blocks), pellets, seed, and worm. Mole baits are sold as worm containing 0.025% bromethalin, whereas rat and mouse baits contain 0.01% bromethalin. Bromethalin and its main metabolite desmobromethalin are strong uncouplers of oxidative phosphorylation. This results in intra-myelin fluid accumulation, leading to long nerve demyelination and intra-myelin cerebral edema. The net result is cerebral and spinal edema and increased CSF pressure, leading to neurologic dysfunction. In toxicity trials, the oral toxic dose of bromethalin when used as part of bait appears to be much lower than the dose administered as a technical grade agent. For example, in dogs, an average lethal dose of technical grade bromethalin is reported to be 4.7 mg/kg but 2.38 mg/kg in bait. Young dogs (<1 yr old) appear more sensitive; death has been reported at dosages of ~1 mg/kg in bait. Dogs are more commonly involved. Cats are 2–3 times more sensitive than dogs.”

 

 

 

 

 

 

 

 

What is the risk with mole baits?
The level of risk of any pesticide depends on a combination of toxicity and exposure. Anytime you are considering using a toxicant or other pesticide, first read the label in its entirety. Labels will contain information on how to apply a product safely, under what circumstances, and any precautions you should take. However, labels also contain other information that can users determine if they should use a product. This information is key in preventing pesticide exposure to people and the environment. In fact the label is a legal document. The pesticide user is bound by law to follow all label directions. Label directions for mole baits instruct users to keep pets out of treated areas and not to use the product above ground. Bait must be applied directly into moles’ tunnel systems. Following these directions will greatly reduce, or even eliminate, the exposure risk to pets. What might be the consequences if your dog or a neighbor’s dog mistakenly entered your yard and went digging around in a treated area?

To determine this we can calculate how much bait a dog would have to consume to reach the average lethal dose. The more technical term is the LD₅₀ dose which is the individual dose that kills 50 percent of a population of test animals. A single worm mole bait weighs approximately 5g since a package of 20 worms has a weight of 100g.  With 0.025% active ingredient, each worm would contain 1.25 mg of bromethalin. Thus, an 11lb (5kg) dog would need to consume 18 to 19 worms to reach the average lethal dose using the 4.7 mg/kg level for technical grade bromethalin, or 9 to 10 worms for the 2.38 mg/kg level in bait. Recall, these rates were listed in the Merk Veterinary Manual. The amount of bait consumption would be more for larger dogs. The average lethal dose is just that – an average. Some dogs would die with lower dosages and some with higher dosages within a specified timeframe.

It would be extremely unlikely that a dog could find, dig up, and consume the number of worms to reach or even approach the average lethal dose. Consider the following:

• How many worm baits will you use? According to label directions, worm baits are placed underground every 5 to 10 feet in active subsurface runways. Worms may be placed in the deeper underground runways. Limiting their use to only active runways reduces the amount of product applied. The label directions outline the procedure for identifying active runways.
• Applying the product according to label instructions (in underground active mole tunnels) helps minimize the risk of accidental ingestion. However there are additional strategies to prevent accidental ingestion of the bait, including: applying the product in areas inaccessible to pets or installing barriers, covering the application sites with pavers, and supervising the pet’s use of the yard (especially important for dogs that like to dig). Allow at least two weeks (or longer under dry conditions) for breakdown of any uneaten worms.
• Toxic baits placed in runways breakdown over time. That is, a treated area is not treated forever. This is a direct quote from one manufacturer, “Uneaten worms typically remain intact up to 14 days in mole runs. The amount of time it takes for the Mole Killer worm to degrade depends on soil type and the weather. Frequent and heavy rain or high temperatures may accelerate worm degradation. The active ingredient takes longer to degrade.”
• Toxic baits may be combined with other methods. For example, you may choose to limit use of toxic baits only in areas where the soil type or tunnel structure make trapping difficult.

In the end, it is up to the individual user on whether or not they choose to use toxic baits to get rid of moles in their yard. If you do choose to use them, read the label in its entirety. In the case of mole toxicants, the label clearly states that pets should not be allowed in treated areas. If you are not confident this is possible, then alternative control options are likely a better option for you.

Resources
Pesticides and personal safety (pdf), Purdue Pesticide Program
Pesticides and wildlife (pdf), Purdue Pesticide Program
Moles, The Education Store, Purdue Extension resource center
Adjuvants and the Power of the Spray Droplet: Improving the Performance of Pesticide Applications, The Education Store
Purdue Extension – FNR: Ask An Expert, Video, Purdue Extension –  Forestry and Natural Resources YouTube channel

Brian MacGowan, Wildlife Extension Specialist
Purdue University, Department of Forestry and Natural Resources

---

Garlic mustard is an invasive herbaceous plant that is shade tolerant and can invade our forest understories. In its second growing season it produces a flower which releases many seeds. In the video below, Purdue Extension forester Lenny Farlee will share what options we have to help control it.

If you have any questions regarding trees, forests, wildlife, wood products or other natural resource topics, feel free to contact us by using our Ask an Expert web page.

Resources
A Woodland Management Moment, Playlist, Purdue Extension – Forestry and Natural Resources Youtube Channel
Invasive Species, Playlist
Woodland Stewardship for Landowners, Playlist
Investing in Indiana Woodlands, The Education Store, Purdue Extension resource center
Invasive plants: impact on environment and people, The Education Store
Woodland Invaders, Got Nature? Blog

Lenny Farlee, Sustaining Hardwood Extension Specialist
Purdue University Department of Forestry and Natural Resources

---

Do you need to open up your woodlands in order to grow new species of trees/shrubs that need extra sunlight or to make for a better wildlife habitat? Forest openings allows us to regenerate species of trees and shrubs that demand full sunlight and also ensures good diversity of species on your property. In this Woodland Management Moment video, Purdue Extension forester Lenny Farlee talks about creating forest openings.

If you have any questions regarding trees, forests, wildlife, wood products or other natural resource topics, feel free to contact us by using our Ask an Expert web page.

Resources
Woodland Management Moment – Deer Fencing, Video, Purdue Extension – Forestry and Natural Resources Youtube Channel
Asian Bush Honeysuckle, Video, Purdue Extension Youtube Channel
Forest Improvement Handbook, The Education Store, Purdue Extension Resource Center
Woodland Stewardship for Landowners, invasive species along with timber resources, Purdue Extension-FNR YouTube Playlist
Managing Your Woods for White-Tailed Deer, The Education Store

Lenny Farlee, Sustaining Hardwood Extension Specialist
Purdue University Department of Forestry and Natural Resources

---

Purdue urban forester Lindsey Purcell talks about a common planting problem for trees or shrubs that can possibly kill your tree: planting too deep. In the video below he helps you identify the issue and how to remedy it. Follow Purdue Extension – Forestry and Natural Resources Youtube channel for more useful tree planting tips.

Resources
Tree Pruning Essentials, FNR-541-WV, Video, Purdue Extension Youtube Channel
Mechanical Damage to Trees: Mowing and Maintenance Equipment, The Education Store
Tree Installation Process and Practices, The Education Store
Tree Planting Part 1: Choosing a Tree, The Education Store
Tree Planting Part 2: Planting Your Tree, The Education Store
Surface Root Syndrome, The Education Store
Tree Appraisal and the Value of Trees, The Education Store
Question: What are these pretty green flower shaped growth spots? Will they damage the tree?, Got Nature? Post, Purdue FNR Extension

Lindsey Purcell, Urban Forestry Specialist
Purdue University, Department of Forestry and Natural Resources

---

Are you noticing more birds in your backyard recently since sheltering at home? Do you wish you knew how to identify what you are seeing? Do you know what kind of food to put out to attract different species?

Dr. Barny Dunning, professor of wildlife ecology, and Purdue extension wildlife specialist Brian MacGowan offer advice on birdwatching for birders of all skill levels, including how to bring species to your yard, what apps you can use to identify them and other resources to help you learn more in this Facebook Ask the Expert.

Resources
Sibley Guide to Birds app
Merlin Bird App
Audubon Bird Guide App
Cornell University Ornithology Lab website
Migratory Bird Treaty Act
Project FeederWatch from The Cornell Lab
Nesting Box Information – National Wildlife Federation
Project Feeder Watch
Indiana Audubon Society
Sycamore Audubon Society
Attract Hummingbirds to Your Yard, Video, Purdue Extension YouTube Channel
Birds and residential window strikes: Tips for prevention, The Education Store, Purdue Extension Resource Center
No room at the inn: suburban backyards and migratory birds, The Education Store
Size Does Matter – Nest Boxes for Wildlife, The Education Store

John B Dunning, Professor of Wildlife Ecology
Purdue Forestry and Natural Resources

---

On May 5^th, we held a Facebook LIVE: Ask an Expert with several FNR specialists and one of the questions that came in is a question I receive often.

One of the many benefits of interacting with farmers and land managers is I learn about the problems you face. A question came in around the 17:30 minute mark of how to deal with vole damage problems in their 3- to 5-acre pumpkin patch.  I didn’t have an answer regarding registered pesticides (including taste repellents and toxicants) that are labeled for voles in pumpkins. Doing a broad search on the internet is helpful but it is hard to figure out what you can use in your state. Pesticides are often labeled for use in one state but not others. Luckily, anyone can search for registered pesticides online at on the National Pesticide Information Retrieval System. Most states, including Indiana, are included. You can search by EPA registration number, product name, company name, or active ingredient.  A particular search can still yield many choices but this is a helpful way of finding out what is available. Each product has a link to the EPA website that includes product labels.

Since our program last week, I did some checking and found a product registered in Indiana labeled for voles in pumpkins as well as many other crops. Millers Hot Sauce is a taste repellent with an active ingredient of capsaicin (2.5% by weight), which is an irritant to animals, but one some people enjoy in hot peppers. Per label instructions adding an antitranspirant film former or a sticker may prolong the effectiveness of the product.  Mix the product and additives with water according to label instructions. For heavy damage, start treatment after first true leaves appear and continue treatment every 7 days.  If applying to transplants, start application one week after transplanting and continue every 7 days.

Always read the label completely before applying any pesticide. The efficacy of any repellent depends on a number of factors including animal population size and density, available food, and availability of cover. With voles, the year can be key because their populations tend to cycle. Combining other methods with repellents can often increase success. For example, soil cultivation within plant rows and in adjacent habitat can help reduce the habitat quality for voles. Cultivation can also directly kill some voles. There are of course tradeoffs and every situation is unique. Soil cultivation would not be an option in some cases (e.g., adjacent to water, steep slopes). I was unable to find a toxicant registered for voles in pumpkins. But depending on what the land cover is adjacent to the pumpkin patches, some of these may be appropriate in those areas.

With face-to-face Extension programs on hold for the foreseeable future, look for more live Q&A sessions and other programs on Facebook (PurdueFNR) or Twitter (@PurdueFNR).

Resources
National Pesticide Information Retrieval System
Midwest Fruit Pest Management Guide, The Education Store, Purdue Extension resource center
Hops Production in Indiana: Integrated Pest Management Guide for Hops in Indiana, The Education Store
Turfgrass Insects: Managing Black Cutworms in Turfgrass, The Education Store
Applied Research in Field Crop Pathology for Indiana – 2019, The Education Store
Managing Alfalfa Autotoxicity, The Education Store

Brian MacGowan, Wildlife Extensions Specialist
Purdue Forestry and Natural Resources

---

Resourceful Animal Relationships is one unit in a series available from The Nature of Teaching – the place to go for teaching resources that focus on wildlife, food waste, health and wellness. In this series teachers can find free lesson plans, printables, posters, a photo library, information on upcoming workshops and more.

This lesson will teach third- through fifth-grade students about different kinds of organism interactions and how those interactions affect the ways in which organisms gain or lose resources. Students will learn how to describe the differences between mutualism, parasitism,
and competition along with how to explain the different effects that relationships have on an organism and their resources.

It meets several grade-appropriate Next Generation Science Standards, English/Language Arts Standards, and Math Standards. This 19-page pdf is written by Dr. Rod Williams.

For more resources, please check the Education Store.

Resources
Benefits of Connecting with Nature, The Education Store, Purdue Extension resource center
The Nature of Teaching: Ecotoxicology and Environmental Health, The Education Store
The Nature of Teaching: Disease Ecology, The Education Store
The Nature of Teaching: Adaptations for Aquatic Amphibians, The Education Store
Adaptations for Aquatic Amphibians Activity 2: Water Quality Sneak Peak, Video, Purdue Extension YouTube channel

Rod Williams, Professor of Wildlife Science
Purdue University Department of Forestry and Natural Resources

---

The Nature of Teaching: Disease Ecology is one unit in a series available from The Nature of Teaching – the place to go for teaching resources that focus on wildlife, food waste, health and wellness. In this series teachers can find free lesson plans, printables, posters, a photo library, information on upcoming workshops and more.

This unit introduces students to basic principles of disease ecology, including the diversity of parasites, how diseases are modeled, and how parasites and hosts interact. It includes three lessons with colorful animal cards to print along with worksheets and presentation.
Lesson 1: Parasite Diversity Activity
Lesson 2: Modeling Disease Transmission
Lesson 3: Parasite Avoidance Behavior in Tadpoles

This 33-page download PDF is written by Dr. Jason Hoverman; Logan Billet, Rebecca Koetz and Dr. Rod Williams.

For more resources, please check the Education Store.

Resources
Benefits of Connecting with Nature, The Education Store, Purdue Extension resource center
The Nature of Teaching: Ecotoxicology and Environmental Health, The Education Store
Resourceful Animal Relationships, The Education Store
The Nature of Teaching: Food Waste and the Environment, The Education Store

Rod Williams, Professor of Wildlife Science
Purdue University Department of Forestry and Natural Resources

---