Got Nature? Blog

Woodland owners interested in learning more about the ecology and management of their woodlands may enroll in this Purdue University Extension course providing eight weekly meetings and two half-day Saturday field tours. Topics covered include tree identification, forest biology, management planning and practices, economics and financial aspects of woodland ownership, marketing timber, wildlife management, and where to find information and assistance. Participants will be provided with a flash drive containing over 100 reference publications, a tree measuring stick, and additional handout materials at each meeting. Registration is $50 for individuals and $30 for each additional family member.

Dates: Thursdays March 7 to April 25
Time: 6 to 9 pm
Location: Vermillion County Fairgrounds, Cayuga, IN

You can find additional program details and registration information by viewing the Purdue Extension-FNR Calendar. For any questions feel free to contact Lenny Farlee, Extension Forester at lfarlee@purdue.edu or call him at 765 494-2153.

Resources
New Issue of Indiana Woodland Steward now Available, Got Nature? Purdue Extension FNR
Tax Information For Woodland Owners, Got Nature? Purdue Extension FNR
Forest Improvement Handbook, The Education Store

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

Phil Cox, Extension Specialist
Agriculture & Natural Resources

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This latest cold snap could kill some emerald ash borer populations in northern states like Minnesota. But in warmer states like Indiana, the invasive borer is one resilient bug.

 

Resources
New Hope for Fighting Ash Borer, Got Nature? Purdue Extension-FNR
Invasive Pest Species: Tools for Staging and Managing EAB in the Urban Forest, Got Nature?
Emerald Ash Borer, Purdue Extension-Entomology
Emerald Ash Borer Cost Calculator – Purdue Extension Entomology

WFIU Public Radio and WTIU Public Television
Indiana University

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This looks to be shaping up as a tough winter for us and our trees. Lots of snow and ice are predicted for the Hoosier state and this can be a challenge for our trees and shrubs.

After a heavy snowfall, protect your trees and property with these simple tips:

Do not shake limbs to try to remove snow or ice.
When you find your trees are bending or drooping as a result of ice or snow accumulation, your first instinct is probably to shake the branches or knock the weight off with a broom or something similar. This may cause worse damage or actually cause the branch to snap off. Stop right there! Healthy tree branches are flexible, so knocking off the accumulation of snow or ice accretion may cause them to “snap” back, potentially damaging their food and water transport system. The results of the damage may not be evident until next spring.

Trees that tend to suffer the worst damage as a result of snow and ice are upright evergreens, like arborvitae and juniper, and clump trees, like birch. And, when it comes to ice, age does not make a tree stronger; younger trees are better at actually overcoming damage in ice storms.

Hire a Professional.

Safely remove broken limbs.
Broken and hanging branches can be a threat to people and property. If a limb breaks off from the weight of ice or snow and remains in the tree canopy, have it removed and the remaining stub properly pruned to the branch collar as soon as weather allows. The tree will recover better when properly pruned. For undamaged limbs bending under the weight of ice or snow, don’t prune as a means of correcting the situation. Be patient. It takes time for wood fibers in the limbs to return to its natural position.

Always be mindful of walking or parking under branches loaded down by snow or ice as they may snap and fall, causing injury or damage. If a limb breaks and becomes entangled in power lines, notify your utility company immediately. Never approach a downed power line or a branch touching a utility line.

If there is substantial damage to your tree, have an arborist examine damaged branches and limbs for signs of weakness and injury for reparations. It is best to always hire an ISA Certified Arborist. To find an arborist in your area, visit the website, www.treesaregood.org

How can you help prevent ice damage to trees? Proper pruning is one way. Particularly important is the removal of poor branch attachments and weak branch structure in the tree, prior to winter. For more information on pruning, download the publication, Tree Pruning Essentials.

Full article published in the Purdue Landscape Report.

Resources
Avoid Deadly Risk of Dying Ash Trees with Timely Tree Removal, Got Nature? Purdue Extension-FNR
New Hope for Fighting Ash Borer, Got Nature? Purdue Extension-FNR
Invasive Pest Species: Tools for Staging and Managing EAB in the Urban Forest, Got Nature?
Emerald Ash Borer, Purdue Extension-Entomology
Emerald Ash Borer Cost Calculator – Purdue Extension Entomology
Corrective Pruning for Deciduous Trees, The Education Store, Extension Publications

Lindsey Purcell, Urban Forestry Specialist
Purdue Forestry and Natural Resources

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Groundhogs are good at many things, said Brian MacGowan, Purdue University Extension wildlife specialist and Forestry and Natural Resources Extension coordinator, but predicting the weather definitely isn’t one of them.

The lore surrounding Groundhog Day originated in Germany where people used the reactions of badgers and hedgehogs to gauge weather patterns. When the tradition eventually migrated to America, Jarred Brooke, Extension wildlife specialist, said hedgehogs, which can be found throughout the United States, became the mammalian forecaster of choice.

“They’re crafty little critters,” McGowan explains, “which is why they’re found in so many different places. They’re habitat generalists and can live in open woodlands, grasslands, what have you.”

While MacGowan and Brooke agreed groundhogs don’t have a great track-record of weather prediction, other facts make groundhogs one of the more interesting members of the squirrel-family.

For full article see: Groundhogs can’t predict the weather but they do poop underground.

Resources:
Selecting a Nuisance Wildlife Control Professional – The Education Store, Purdue Extension Resource Center
Preventing Wildlife Damage – Do You Need a Permit? – The Education Store
The Basics of Managing Wildlife on Agricultural Lands – The Education Store
Nuisance Wildlife – Indiana Department of Natural Resources
Dealing with nuisance geese this spring – Got Nature?
Animal Damage Management: Woodchucks, The Education Store

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

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Emerald ash borer (EAB), the most destructive forest pest to enter North America has left hundreds of millions of dead ash trees in its wake.  Although this pest has been found throughout our state, many of Indiana’s ash trees are still alive, or dead and still standing.  Ash trees killed by emerald ash borer, become extremely brittle and break easily as they decline. Branches can fall on people and property in snowstorms, with a light breeze, or even on a calm clear day. Danger could be hanging over your head in the street, in the forest, and even in your backyard.

Why does emerald ash borer make ash trees so brittle?

Unlike elms, oaks, and maples, ash trees use a thin ring of conducting tissue to supply water from the roots to the entire tree.  Emerald ash borer grubs will damage these functional water pipes as they chew just beneath the bark inside trunks and branches. This causes the tree to dry quickly and the structural wood to become prone to cracking. Internal breaks in the structural wood that bear the weight of the tree are often hidden from view by tree bark. As such, limbs can break and fall at any point along the branch at any time. It is not uncommon to have sizable limbs snap 30 feet off the ground on a calm day.

The threat of falling limbs is not limited to just dead ash. A comparative study of ash trees conducted in Ohio shows that structural integrity of ash trees can begin to decline even when trees are mostly green and have two thirds of the canopy still intact.

What should I do to protect myself from falling ash trees and limbs?

If the tree has lost more than 30% of the canopy, make plans to remove it.  Delaying removal allows the tree to become more brittle and the problem more dangerous.  Remember, EAB causes progressively more injury to ash trees as time goes on.  The dead parts never come back to life.

If you have been treating your tree continue to do so.

How should I remove the tree?

To minimize risk of harm, hire a trained professional who has experience removing emerald ash borer damaged trees. The International Society of Arboriculture maintains a directory of Certified Arborists and their credentials. They can help find an arborist near you.  Always get bids from more than one contractor. Be sure your contractor is insured and bonded in case of an accident. Professionals are happy to share this information.

Some homeowners might be hesitant to remove dead ash trees because they provide valuable habitat for a range of woodland animals and mushrooms. However, we do not recommend keeping them standing unless you can guarantee that no people, domesticated animals, or property will ever be in their path if they fall. If you have a dead tree that can’t be felled right away or ever, stay away from it until after it has fallen.

Article courtesy of the Landscape Report.

Resources:
New Hope for Fighting Ash Borer, Got Nature? Purdue Extension-FNR
Invasive Pest Species: Tools for Staging and Managing EAB in the Urban Forest, Got Nature?
Emerald Ash Borer, Purdue Extension-Entomology
Emerald Ash Borer Cost Calculator – Purdue Extension Entomology

Lindsey Purcell, Urban Forestry Specialist
Purdue Forestry and Natural Resources

Elizabeth Barnes, Exotic Forest Pest Educator
Purdue Entomology

Cliff Sadof, Professor, Ornamental, Pest Management
Purdue Entomology Extension Coordinator

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With winter upon us this is actually a good time to look for owls on your property.  Most owls breed from January to March. You can either listen for calls in the evening, or use owl calls or recorded calls to get responses from owls in the area. We have three common species in Indiana and one rare species. All are non-migratory.  However, each has different needs and habits. The following descriptions were written by Barny Dunning, professor of wildlife ecology at Purdue, and Jeff Riegel, field project supervisor at Purdue. These accounts were originally published in the Indiana Woodland Steward (www.inwoodlands.org).

Owls are among the most intriguing animals native to Indiana. They have been celebrated in story from the myths of the early Greeks to the books of Harry Potter. Owls are common across much of the state, but are relatively unknown, probably because of the nocturnal habits of these birds. But since they are efficient predators of mice and rats, among other things, owls are very useful birds to have around. Three species of owls are common year-round residents in Hoosier forests. The largest of these is the great horned owl, one of the dominant predators of our forests. Most people are surprised to learn that the great horned owl is as common as the familiar redtailed hawk even though the owl is much less likely to be seen.

Great horned owls hunt in open areas but nest in large trees, where they take over a nest abandoned by a hawk, crow or heron. They are common where both woods and fields mix. The owls start breeding in January and February, adding new sticks to an old nest and laying a clutch of three eggs. Most species of owls nest very early in the year so that there will be a lot of easily caught prey in the form of young mammals and birds when the owl chicks are learning to hunt on their own. Many nests of the great horned owl are in snags or trees with broken tops, therefore retaining some of these forest features will provide good nesting spots for this dominant bird.

A second species of large owl is found in the larger woodlands of Indiana. The barred owl is most common in the interiors of forests and spends less time along the woodland edge. One major reason for this is the presence of the great horned owls, which will kill and eat a barred owl. Barred owls usually nest in the cavities of deciduous trees, laying their eggs in deep winter. Their dependence on tree cavities means that barred owls are likely to respond well to land management activities that retain large trees on a property and increase the number of snags with cavities. They also do well when there are forest patches of a variety of ages on a property, in addition to the older trees that provide nest sites.

Eastern screech-owls are the smallest resident owl in the state. They nest in small tree cavities and readily make use of nest boxes made especially for them. More than the other two species, screech-owls are found in suburban backyards, urban parks and on college campuses – anywhere there is a variety of trees and shrubs. Screech-owls feed on small prey such as insects, songbirds and mice. They breed later than do the big owls, and have active nests in March and April. In addition to nest boxes, these owls willuse old cavities excavated by northern flickers, tree holes created by storm damage, and hollow trunksof snags. Their ready use of a wide variety of cavity types makes our screech-owls a prime beneficiaryof snag retention and other habitat improvement activities. Indiana’s smallest owl does not breed here, but its numbers during the fall migration can be in the thousands statewide. The northern saw-whet owlbreeds from the most northern states on into Canada and migrates from there when food becomes scarce. “Swets” are an irruptive species, meaning their populations rise and fall dramatically from one year to the next on a roughly four-year cycle. A group of volunteer researchers in Yellowwood State Forest began studying the movements of these owls in 2002 as part of the larger Project Owlnet (www.projectowlnet.org). Their first year produced 71 owls on just one ridge in Yellowwood. Since then, the annual numbers have averaged around 70, but nearly 200 owls were captured and banded on that same ridge in 2007. The low point in the cycle was in 2009 when only nine owls were captured. There are now eight such banding stations scattered around Indiana. Brookeville Reservoir had the largest number of captures in 2009 with 32; while an Indianapolis station tallied only six. Some northern saw-whet owls winter in Indiana where forests with an open understory provide good foraging  opportunities throughout the winter months.

The rarest owl in Indiana is, paradoxically, the species with the largest geographic range. Barn owls are found across the globe, but in the Midwestern United States their populations have declined dramatically. The species is considered endangered in Indiana. Barn owls originally nested in tree cavities, but when early settlers built barns and other farm buildings, the owls were quick to adapt. They are not limited to barns however, as recent Hoosier nests have been found in old churches, silos, and within the walls of abandoned buildings. To be suitable, human structures must have openings that allow the owls to fly in and out and an interior area that is  undisturbed and big enough for the nest. The biggest factor in their decline has been changing agricultural practices. Barn owls hunt in open areas such as pastures, but do not use rowcrop fields. As Hoosier farmers converted pastures to corn and soybean, the barn owl lost its hunting grounds. Farmers in the southern part of the state that still retain some open grassy fields on their land can contact the state Department of Natural Resources to have a barn owl nest box added to their outbuildings if they don’t have appropriate nest sites.

Resources
Learn how forests are used by birds new videos, Got Nature? Blog
Managing Woodlands for Birds, The Education Store-Purdue Extension resource center
Climate Change + Birds, Purdue Climate Change Research Center

National Audubon Society
The Cornell Lab of Ornithology

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

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This unit highlights the resources required to produce food and the food wasted along each step of the food production system. It contains two lessons: Producers, Consumers, and Natural Resources; and Food Waste from Farm to Fork, along with all necessary overviews, notes, and resources.

For more details and free downloadable PDF see FNR-558-W publication at The Education Store: Food Waste and Natural Resources Lesson Plans.

Resources
What a Waste of Food!, lesson plans, The Education Store, Purdue Extension’s resource center
Food Waste Lesson Plans, Nature of Teaching

Rebecca Busse, Nature of Teaching Program Coordinator
Purdue Department of Forestry and Natural Resources

Rod N Williams, Engagement Faculty Fellow & Associate Professor of Wildlife Science
Purdue University Department of Forestry and Natural Resources

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How do I remedy poor branching? Is my tree at risk of splitting, and how can pruning prevent that? Corrective pruning has many implications for tree structure, health, and longevity. Developing a strong, central branch structure in a deciduous tree is critical for preventing structural failure caused by storms, wind, and ice. This 8-page publication explains the problems resulting from a co-dominant stem structure and addresses pruning strategies for correcting poor structure.

To view this full publication please go to Corrective Pruning for Deciduous Trees located in The Education Store, Purdue Extension’s resource center.

Resources
Preparations to Prevent Southwest Tree Injury, Got Nature? Blog
When do you stake a tree?, Got Nature? Blog
Top 5 List for Tree Selection and Planting, Got Nature? Blog
Tree Selection for the “Un-natural” Environment, The Education Store, Purdue Extension
Tree Support Systems, The Education Store, Purdue Extension
Tree Installation: Process and Practices, The Education Store, Purdue Extension
Planting Your Tree Part 1: Choosing Your Tree, video, The Education Store, Purdue Extension

Lindsey Purcell, Urban Forestry Specialist
Purdue Forestry and Natural Resources

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The latest Wildlife Bulletin, provided by the Indiana Department of Natural Resources-Division of Fish and Wildlife, has all the Indiana hunting information you need to know along with upcoming events and resources. Topics include: Get your deer licenses now; Deer hunting checklist; Deer processing videos on YouTube; Hunting seasons dates; Four options to check in game; Sandhill crane migration at Jasper-Pulaski; and much more.

The Wild Bulletin is a free email newsletter offering information about Indiana’s fish and wildlife resources and recreation opportunities. Subjects covered include profiles, information about hunting and fishing season dates, regulation updates, wildlife and fisheries research status reports, tips on wildlife watching and reminders about important dates for Hoosier outdoor enthusiasts.

To subscribe to this free e-newsletter visit Wild Bulletin, Indiana Department of Natural Resources.

Other resources:
State Parks, Indiana Department of Natural Resources (IN DNR)
Outdoor Indiana, Indiana Department of Natural Resources (IN DNR)
Deer YouTube Video List, Purdue Extension-Forestry and Natural Resources and IN DNR

Indiana Department of Natural Resources

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The time is now to start protecting your trees!  Now that your ears are perked up, let’s talk a bit about Southwest injury on trees.

Bark cracking (Fig.1) is a phenomenon that occurs in many species of trees and can have many causes. One of the most common types of bark cracking is termed Southwest injury. Southwest injury occurs during the winter months on the lower section of the trunk on the southwest side. This happens when there is a sudden temperature drop, for example, the sun going behind a cloud during the winter. The freeze-thaw cycle happens very quickly when there is a change from very warm to cold conditions, which results in a crack. If there is a snow pack, the reflection of sunlight on the bark will actually increase the temperature in the bark.

Usually Southwest injury occurs on thin-barked trees, such as Acer spp., Cercis spp., Malus spp., and many others (Fig. 3). A thin-barked tree lacks the amount of cork cells in thicker-barked trees, thus allowing the vascular tissue to be located very close to the bark.  Thick bark trees tend to be more resistant to cracking due to a greater lag in the freeze/thaw cycle. Trees that are under stress due to environmental factors, herbicide injury, and/or insect and disease are more susceptible to cracking.

No matter the initial cause of the crack, the common denominator of a crack in the bark is a pre-set wound. The freeze-thaw cycle during the cold months causes the point of injury to expand and contract. Like with your vehicle windshield, a small point of injury in bark will expand and contract due to sudden heating or cooling, thus causing a large crack.

Any type of cracking that occurs, originates from a point of injury, such as a pruning or other mechanical injury. These are horizontal cracks that can range from <1” to the entire length of the trunk, though are usually localized near the bottom of the trunk (Fig. 4).

Once trees are greater than about four inch caliper, the likelihood of Southwest injury is diminished.  On trees four inches or less, tree guards (also called tree wraps) should be installed over each trunk.

White tree guards may help prevent this from occurring due to the reflection of the sun, preventing overheating on the bottom of the trunk (Fig. 5) In order to prevent cracking, try to prevent any type of mechanical damage that could cause cracking in the winter. Bark cracks become visible most often during the late winter/early spring. Tree guards should be removed in the spring, because the guards become a problem with disease due to moisture within the guard.

In some circumstances a healthy plant may heal, partitioning off the damaged area, but the bark on a plant under stress, due to drought, herbicide damage, etc., may last the entire life of the tree.

For full article, check out the Landscape Report

Resources
Trees and Storms, The Education Store
Pruning Ornamental Trees and Shrubs, The Education Store
Why Hire an Arborist, The Education Store
Why Is My Tree Dying? The Education Store
Weeping Cherry Trees Appear to be Damaged or Dead. Was This Past Winter Hard on These Types of Trees?, Got Nature? Blog

Lindsey Purcell, Urban Forestry Specialist
Purdue Forestry and Natural Resources

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