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March 05
Snap, Crackle and Pop - Walking in a winter wonderland
Snow covered forest

"When it snows…
and temperatures drop
That’s when you’ll hear
The Snap, Crackle, and Pop"

Few things can compare to the peacefulness of walking in a forest filled with snow covered trees until you hear a snap, crackle, or an explosive “POP” echoing through the woods. What on earth was that? If the noise is followed by a “whoosh” it may be a limb that just broke and crashed to the ground. If it sounded like a gunshot but nobody is there, you may be listening to the sound of a frost crack forming on a tree. 

What are frost cracks?
Nobody knows for sure. You may hear one happen, typically on a cold late winter morning after a warm spell. They sound like muffled to loud rifle shots. Typically, these cracks occur on the south side of the trunk between two and five feet up the tree (when measuring from the ground). With leaves on, water is pulled upwards from tree roots through the xylem vessels by the differences in water potential from the air to the soil, and escapes through the leaves (the soil-plant-air continuum).

Water in the plant is under a negative water potential or in common terms – under tension. In the winter, when deciduous trees have no leaves, the water pressure in the sap becomes positive. A flow occurs where water moves up in the xylem and cycles down in the phloem (food conducting cells). The mechanism of this winter flow in temperate trees is not well understood physiologically. The sap increases in simple soluble sugars as the cold weather begins and increases until midwinter to work like antifreeze, depressing the freezing point of water. This is why maple syrup can be tapped in late winter. 

Forest CrackScientists are challenged to study the phenomena of frost cracks. They involve thousands of xylem vessels in a very narrow vertical line bursting all at once – as if a line of sap is too low in sugar concentration – and then freezes hard explosively bursting the vessels. After several growing seasons, most trees will heal over the crack but callus growth makes them appear wider. Valuable timber logs can still be profitably harvested with frost cracks as millers can cut through them to minimize the defect. 

Species with darker colored bark and thinner bark can be affected by frost cracks. Some genotype effects have been found in black walnuts at Purdue. Field conditions and topography that effect cold air movement can affect frost cracks. Most form on the southwestern section of the trunk, the area most affected by warming from sunlight during winter afternoons. Somehow, this conditioning sets up the tree when temperatures plummet to single digits (in Fahrenheit) or lower, especially after a warmer period. 

So, if you wander through the woods this winter; stop and don’t “drop” when you are listening to the sounds of the trees.

"When the snow twinkles
and the skies are bare…
Temperatures drop
and a chill fills the air
If you listen real close
and adjust your cap
You just might hear
a tree go “Snap!”

Bark Splitting on Trees, Cornell University
How do trees survive winter? video, MinuteEarth
Winterize Your Trees​, The Education Store

Shaneka Lawson, Adjunct Assistant Professor
Department of Forestry and Natural Resources 

James McKenna, Operational Tree Breeder
Department of Forestry and Natural Resources​​​​​

March 03
Plants and soil absorb unwanted water runoff, how?

Landscape, Purdue Rainscaping Education Program Purdue University, Agriculture News has just announced a new program - Purdue Rainscaping Education Program.

"Purdue Extension is starting a program that will provide training and resources on "rainscaping" practices used in residential gardens or small-scale public spaces to reduce pollution from runoff.

The Purdue Rainscaping Education Program will begin in April with pilot workshops focusing on planning, installing and maintaining rain gardens. The workshops will train Purdue master gardeners, personnel in conservation agencies and organizations, storm water professionals, and landscape professionals and consultants.

"Participants will visit and discuss existing rain gardens in the community, then learn how to site, design, construct and maintain a rain garden with a focus on community education," said Kara Salazar, sustainable communities Extension specialist.

Rainscaping uses landscape design and management practices - at both the household and community scales, such as at schools, community centers and fairgrounds - that enable plants and soils to absorb storm water, reducing runoff from fertilizers and other pollutants that eventually reaches lakes, streams and rivers." Read more...

The program offers five sessions on Mondays from April 6th to May 4th from 3-6pm. View the Purdue Rainscaping Education Program brochure for more details. Registration is now open at The Education Store.

Purdue Rainscaping Education Program, Purdue Agriculture
Sustainable Communities, Purdue University Extension
Climate Change: How will you manage stormwater runoff?​, The Education Store

Kara Salazar, Sustainable Communities Extension Specialist
Department of Forestry and Natural Resources & Illinois-Indiana Sea Grant

John Orick, Purdue Master Gardener State Coordinator
Department of Horticulutre and Landscape Architecture

March 02
New Podcast! Giant Salamanders Part 1: climate change and immune function
Dr. Kimberly Terrell with hellbenderDr. Kimberly Terrell holds an eastern hellbender caught during a stream survey in southwest Virginia. Photo by JD Kleopfer.

​Eastern hellbenders are one of the largest amphibians on the planet.  They require cool, fast flowing streams and rivers with high levels of oxygen to breathe.  Changes in temperature can affect not only levels of dissolved oxygen in the water, but may invoke changes to the hellbenders immune system as well.  In this podcast our guest host,  Emily McCallen, with the Department of Forestry and Natural Resources, will be interviewing Dr. Kimberly Terrell about how variability in water temperatures may increase immune function in these giant salamanders.

Listen here:
Giant Salamanders Part 1: climate change and immune function, Got Nature? Podcast
iTunes - Got Nature?

To contact Dr. Kimberly Terrell:
Twitter: @snototters
Smithsonian Conservation Biology Institute:

Other resources:

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

March 02
Ohio River Valley Woodlands and Wildlife Workshop
Ohio River Valley Woodlands and Wildlife Workshop

Everyone has a different approach as to how they manage their land. Many times during our management discussions we begin asking ourselves the question, “What‘s next?” The Ohio River Valley Woodlands and Wildlife (ORVWW) Workshop held on March 28, 2015, is designed to provide you, the woodland and wildlife property owner, with forestry and wildlife related educational opportunities. The workshop will provide you with forestry and wildlife experts from Indiana, Kentucky and Ohio who will address the questions and concerns that you have with the management of your properties. View 2015 Ohio River Valley Woodlands and Wildlife Workshop for full details.

Date: March 28, 2015
Time: 9am-3pm
Location: Sharonville Convention Center, 11355 Chester Rd, Cincinnati, OH

Upcoming Extension Events, Purdue Agriculture Calendar
Forest Ecosystem Management in the Central Hardwood Region, The Education Store
Habitat Management and Monitoring, The Education Store

Ohio State University Extension, Ohio Woodland Stewards Program

Brian MacGowan, Extension Wildife Specialist
Department of Forestry and Natural Resources, Purdue Univeristy

February 23
Indiana Tree Farm Landowners Clinic - Workshop

The 2015 Indiana Tree Farm Landowners Clinic is a program designed to provide landowners interested in managing their forests and wild lands an introduction to management practices, and resources for advice and assistance. The program is open to anyone interested in trees and wildlife. Since 1941 the American Tree Farm System has educated and recognized the commitment of private family forestland owners demonstrated in sustainable forest stewardship. We will have tree measuring sticks available for sale. Join us to learn more about Tree Farm and how you can improve your property. This program is offered through the cooperation of the Indiana Tree Farm Committee, the Indiana Department of Natural Resources (INDNR), Division of Forestry, and the Hardwood Tree Improvement and Regeneration Center (HTIRC).

What: 2015 Indiana Tree Farm Landowners Clinic
When/Where:  Friday, March 27, 2015 at  The Reuter Tree Farm from  1-4 p.m.;  Saturday, March 28, 2015 at McCormick's Creek State Park, Spencer, IN from 9 a.m. to 4 p.m.
Registration: Fee of $50 per person or $75 per couple. Must register by March 20, 2015.
See the brochure for more details and registration.

Purdue FNR Events
Forest Improvement Handbook, The Education Store
A Landowner's Guide to Sustainable Forestry: Part 1: Sustainable Forestry - What Does It Mean for Indiana?​, The Education Store

Lenny Farlee,​ Sustaining Hardwood Extension Specialist
Department of Forestry and Natural Resources & HTIRC

Bob Burke, Consulting Forester
Indiana Tree Farm Program

February 22
National Invasive Species Awareness Week
National Invasive Species Awareness Week

Find an event in your area for February 22-28, 2015, National Invasive Species Awareness Week (NISAW). According to experts with the Weed Science Society of America (WSSA), it's a topic that deserves our attention. Non-native plants, animals and pathogens can harm humans and the environment and impact our nation's economy. The damage done by invasive plants alone costs the U.S. an estimated $34.7 billion a year.

The NISAW web site shares how invasive weeds can produce skin irritation, trigger allergies and poison pets and livestock. They can clog waterways, kill native trees, and shade out crops, ornamentals and prized native flora. They are found in every imaginable habitat, including oceans, lakes, streams, wetlands, croplands, rangelands, natural areas, parks, forests, urban environments, yards and gardens.

Check out the National Invasive Species Awareness Week web site and find nine ways you can help along with a list of partners which includes: Weed Science Society of America, Center for Invasive Species and Ecosystem Health, USDA, U.S. Fish and Wildlife Services, USDA National Institute of Food and Agriculture(NIFA), Natural Resources Conservation Service (NRCS), U.S. Department of the Interior Bureau of Land Management, National Park Service, Reduce Risks from Invasive Species Coalition, National Wildlife Refuge System and more.

Upcoming Workshops
Forest Management for the Private Woodland Owner, Feb. 24th, Department of Forestry and Natural Resources (FNR), Extension
Conserving Nature on Your Land, Feb. 27th & 28th, FNR, Extension
Control of Woodland Invasive Species Demonstration, March 6th, Indiana Small Farms Conference, Purdue Agriculture

FNR Workshops​, Department of Forestry and Natural Resources, (FNR)
Purdue Extension Small Farms, Facebook
Got Nature? blog, click on "forestry", FNR
The Education Store, Purdue Extension, place in the search field "invasives"
Invasive Species​, Indiana DNR

Got Nature?
Department of Forestry and Natural Resources

February 20
Purdue partners with Indiana zoos for hellbender conservation
Hellbender conservation.

Purdue University is partnering with three Indiana zoos and the state in a conservation program that will involve raising year-old hellbender salamanders and then a few years later returning them to their southern Indiana habitat to be tracked.

Rod Williams, associate professor of wildlife science and leader of the university's hellbender effort, approached officials at Columbian Park Zoo in Lafayette, Fort Wayne Children's Zoo and Mesker Park Zoo in Evansville about joining the program, which also includes the Indiana Department of Natural Resources.

North America's largest salamander is in decline nationally and is most vulnerable to predators when young. "Mortality can be as high as 99 percent in the wild," Williams said. "By rearing them in captivity for three to four years they will have a much better survival rate." Read full article, Purdue Agriculture News.

Help the Hellbender, Purdue University
Aquaculture Research Lab, Department of Forestry and Natural Resources
The Nature of Teaching, The Education Store, Purdue Extension, place "Nature of Teaching" in search field for list of all lessons available

Rod Williams​, Associate Professor of Wildlife Science
Department of Forestry and Natural Resources (FNR), Purdue University

February 20
Control of Woodland Invasive Species Demonstration
Woodlands, invasive plant species demonstration of control March 6, 2015.

Invasive plants are species that can grow and spread aggressively, mature quickly, and invade an ecosystem causing economic and environmental damage. What a better way to learn about them and how to protect your land than to attend the Control of Woodland Invasive Species Demonstration by Lenny Farlee, sustaining hardwood extension specialist. This event is hosted by the Indiana Small Farm Conference.

Who: Indiana Small Farm Conference
What: Control of Woodland Invasive Species Demonstration
When: March 6th, 11:15-11:45am
Where: Exposition Hall at the Hendricks County Fairgrounds and Conference Center
Details: Registration is still available. Sign up by calling The Education Store at 888.398.4636 today!

There will also be pre-conference workshops taking place on Thursday, March 5, 2015 and more workshops from Friday to Saturday evening. You will find topics from Solar Energy for Small Farms to Bee Health Update and Honey Bee Queen Rearing. View the schedule for more details on the Indiana Small Farm Conference​ web site.

FNR Workshops​, Department of Forestry and Natural Resources, (FNR)
Purdue Extension Small Farms, Facebook
Got Nature? blog, click on "forestry", FNR
National Invasive Species Awareness Week, Feb. 22-28
The Education Store, Purdue Extension, place in the search field "invasives"
Invasive Species​, Indiana DNR

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

February 13
It's Not Too Late to Conserve Nature on Your Land!

​Purdue Extension is hosting a one-day event for homeowners and rural landowners to help them maintain the natural resources on their properties.

Participants can chose to attend one of the two "Conserving Nature on Your Land" workshops -

Date: February 27, 2015
Time: 8:30 a.m. to 3:30 p.m. EST
Location: Whitley County 4-H Center, 680 West Squabuck Road, Columbia City, IN 46725

Date: February 28, 2015
Time: 8:30 a.m. to 3:30 p.m. EST
Location: Turkey Run State Park Inn, 8102 East Park Road, Marshall, IN 47859

The program will provide information for developing and enhancing woods, landscapes and other natural resources. There will be various sessions, so participants can choose those that best suit their interests.

Sessions will include topics on tree identification, wildlife inventory, planting and protecting tree seedlings, and multiple other management discussions.

Brian MacGowan, Purdue Extension wildlife specialist, will give an introduction to the session on natural resources management. "Our program is an opportunity for participants to learn about what interests them the most from leading experts," MacGowan said. "It also provides them a forum to interact with and learn from other homeowners who have shared similar interest in natural resources."

The deadline to register is Feb. 18. Payment of $40 per individual ($55 for couples) must be included with the registration form. Pay online.  View the Conserving Nature on Your Land pamphlet for more details.

Questions? Email Brian MacGowan.

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

February 13
Coyote class to be held in Lafayette

​The Indiana Department of Natural Resources (DNR) will be holding a free program in the Lafayette area to educate the community on coyotes. There has been an increase in coyote sightings recently. They are common in all parts of Indiana. DNR experts will be hosting the meeting and will be discussing waye to reduce conflit with coyotes, questions concerning pet safety and current hunting/trapping regulations. There will also be a meeting in the Fort Wayne and Indianapolis area.

What: Living with Coyotes
Where: 1333 Ivy hall, Ivy Tech, 3101 S. Creasy Lane, Lafayette IN
When: Thursday, February 19th, 6:00 pm to 8:00 pm
Details: Register on the DNR's site. Cost is free.

Education Events, Indiana DNR
Coyote sightings increasing, Got Nature?
DNR provides coyote education class in Lafayette​,

Indiana Department of Natural Resources

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