Journeys of Dr. G at Tyler Arboretum

A sabbatical project, exploring all that Tyler Arboretum has to offer

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Make a #GlobalSelfie with NASA on Earth Day at Tyler Arboretum!

#GlobalSelfie on Earth Day for NASAI hope the title of this blog post has grabbed your attention!  I think this will be a really fun opportunity on Earth Day to get outdoors, take a photo of yourself in the outdoors, and do all of this at Tyler Arboretum!  And who knows… we could get Tyler Arboretum in NASA’s latest mosaic image of planet Earth!

Below, I’ve copied the text from the NASA website on NASA’s #GlobalSelfie Earth Day.  I would suggest getting out to several places across the Tyler property to show the world what incredible diversity is across the arboretum – from the ponds to the serpentine barren!  When you take your selfie, you’ll want to include the sign NASA has created (which can be printed from their website as a JPG or PDF), and I would suggest adding the tag #tylerarboretum to your online posting of your image (using Twitter, Instagram, Facebook, Google+ or Flickr).  This way, we know which Tyler images to look for in NASA’s global collage!

Have fun on Earth Day!


Make a #GlobalSelfie with NASA on Earth Day

NASA invites you — and everyone else on the planet — to take part in a worldwide celebration of Earth Day this year with the agency’s #GlobalSelfie event.

The year 2014 is a big one for NASA Earth science. Five NASA missions designed to gather critical data about our home planet are launching to space this year. NASA is marking this big year for Earth science with a campaign called Earth Right Now, and as part of this campaign the agency is asking for your help this Earth Day, April 22.

While NASA satellites constantly look at Earth from space, on Earth Day we’re asking you to step outside and take a picture of yourself wherever you are on Earth. Then post it to social media using the hashtag #GlobalSelfie.

Here are the details.

What’s a #GlobalSelfie?

Two people pose with a NASA #GlobalSelfie signNASA astronauts brought home the first ever images of the whole planet from space. Now NASA satellites capture new images of Earth every second. For Earth Day we are trying to create an image of Earth from the ground up while also fostering a collection of portraits of the people of Earth. Once those pictures stream around the world on Earth Day, the individual pictures tagged #GlobalSelfie will be used to create a mosaic image of Earth — a new “Blue Marble” built bit by bit with your photos.

Need an idea of what kind of picture to take? Get outside and show us mountains, parks, the sky, rivers, lakes — wherever you are, there’s your picture. Tell us where you are in a sign, words written in the sand, spelled out with rocks — or by using the printable signs we’ve created that are available at the bottom of this linked page.

The Earth mosaic image itself and a video using the images will be put together and released in May.

How do I take part?

We’ll be monitoring photos posted to five social media sites: Twitter, Instagram, Facebook, Google+ and Flickr.

Post your photo to Twitter, Instagram or Google+ using the hashtag #GlobalSelfie, or post it to the #GlobalSelfie event page on Facebook or the #GlobalSelfie group on Flickr.

Why a #GlobalSelfie?

NASA scientists have helped identify thousands of new planets out in the universe in recent years. But the space agency studies no planet more closely than our own. With 17 Earth-observing missions orbiting our home planet right now — and several more launching this year — NASA studies Earth’s atmosphere, land and oceans in all their complexity.

This satellite data helps NASA scientists piece together a clear picture of our planet from a scientific viewpoint. On this Earth Day, we wanted to create a different picture of our planet — a crowd-sourced collection of snapshots of the people of Earth that we could use to create one unique mosaic of the Blue Marble.

So, come April 22, take a second to step outside and join us in celebrating our home planet.

(news story from NASA)


The Frogs are Calling!

Frog information is available at the Tyler Arboretum visitor center!

Frog information is available at the Tyler Arboretum visitor center!

Today is the warmest day yet for 2014, with the forecast predicting a high of 80 degrees!  I headed out to Tyler Arboretum with an objective in mind – timing how long it would take me to hike on the Pink Hill Trail to the Serpentine Barren to start thinking about a fall fieldtrip there with my students.  But as I was heading out on the multi-use trail to exit the fence through door #7, I quickly became distracted by the ponds along the trail (I should clarify – distracted by the NOISES coming from the ponds along the trail!).

To hear what I was hearing, watch/listen to this short video clip (you may need to wait a few seconds for the video to begin – but it is worth the wait!).

Yes, it is that time of year, when the frogs are out at Tyler Arboretum!  I could not believe how many frogs were “singing,” making sure that everyone could hear them when walking towards and away from the ponds.  And the frogs were very easy to spot near the shallow edges of the ponds.  I wish I knew more about these amphibians, as there is quite a bit of diversity among the frogs I was able to spot.  I’ve included some images below.  Just note that as you walk towards the ponds, the frogs will see you coming and probably stop their singing – but only for a moment, before the chorus starts back up again.

As I was going through the Tyler Arboretum website, I came across 12 Months of Fun at Tyler.  If you haven’t explored this new resource, you should certainly check it out.  I was pleased to find that the resources for March included none other than Frogs!  The resource is designed for parents to explore with children, but I found it a great starting point to try to identify the frogs I spotted on my adventure at the Arboretum today.

If anyone can help me with the identifications, please leave a comment below this blog post – and thank you!


Unknown frog #1


Unknown frog #2

Unknown frog #2

Unknown frog #3

Unknown frog #3

Unknown frog #4

Unknown frog #4

And, finally, one final link to another video where I captured the frogs calling out to all Tyler visitors! (no frog images – just enjoy the sounds!)

RANDOM FACT – Just a few days ago, the state of California proposed a bill to name the red-legged frog the official state amphibian!  Read more at The Washington Post.




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Question: Has Tyler Arboretum ever experienced an earthquake?

On April 1, 2014, there was no fooling about the magnitude 8.2 earthquake that occurred offshore of Chile.  Several locations across the globe felt the ground shake and were placed under tsunami warnings.  And then, there was a M7.6 aftershock.  Did you feel these earthquakes?  Or a better question… did Tyler Arboretum feel these earthquakes?

Let me back up and give a quick “Earthquake 101″ tutorial.  An earthquake is a sudden release of energy within the Earth’s crust that can cause destruction and may trigger tsunami formation.  That energy travels throughout the Earth and across the globe, and it is released through two types of energy waves – P waves (or Primary waves) and S waves (Secondary waves).  The P waves are the first to arrive at a location, and think of their movement as stretching a Slinky across the floor, and when you push forward on the Slinky, it compresses and expands the spring, and then when the energy dissipates, it returns to its normal state.  Think of rocks compressing and expanding as the P waves move through the Earth (yes, rocks do that!).  The S waves are the second ones to arrive.  They take longer because they travel through the Earth as if they were a section of stretched rope that was flicked up and down on one end.  The up-and-down wave form moves forward (ultimately), but gets there by doing an up-and-down motion along the length of the rope.  If you want to learn more about earthquakes, check out these great general earthquake resources on the Pennsylvania Earth Science Teachers Association (PAESTA) website, and the US Geological Survey has a helpful image showing the differences between P waves and S waves.

DSCN0350OK, now that you are set on the basics of earthquake the motion and the energy waves that travel through the Earth, I have to introduce a couple of additional terms.  Seismology is the scientific study of earthquake, a seismometer is the instrument that records these P and S waves, and a seismogram is the record we can see of when those energy waves arrive at a station and how intense they were (the Greek term for earthquake is seismos).  There are numerous seismometers across the globe, constantly measuring any ground movement from the energy release.  In fact, one of these seismometers is located right across the street from Tyler Arboretum at Penn State Brandywine!  It is buried in the ground in a secret location on campus, but the image to the left shows the small silver device we have (before it was buried) that is mighty in what it can record!


Below is the seismogram (the digital data recording) that our seismometer puts out.  Each horizontal line represents two hours of time.  The first record below is a snapshot from the April 1st earthquake offshore from Chile and the second one is from the M7.6 aftershock.  Can you see the energy “kick” from the P wave, the light blue right before the 0:00 time on the right in the first image?  And then on the next line, there is a larger, dark blue “kick” from the arrival of the S wave.  This data helps scientists do a little bit of math to then be able to go back and determine the location of the epicenter of the earthquake at the surface (the actual location, at depth, is called the focus of an earthquake).

The M8.2 earthquake, northwest of Iquique, Chile, April 1, 2014.

The M8.2 earthquake, northwest of Iquique, Chile, April 1, 2014, as recorded on the Penn State Brandywine seismometer.

The seismogram from the magnitude 7.6 aftershock from the Chile earthquake.

The seismogram from the magnitude 7.6 aftershock from the Chile earthquake.

Pretty impressive!  So even though you and I did not feel any ground shaking, those energy waves from Chile certainly made it all the way here to Media!

Now who can forget the 2011 Virginia Earthquake that occurred on August 23, 2011, at 1:51 pm EDT?  Yes, many of us did feel the Earth shake, and the Penn State Brandywine seismometer recorded those energy waves as well, in the image below (the X axis is distance in degrees latitude away from the epicenter, the Y axis represents how long it took the signal to arrive to these recording stations after the original energy release).  Looking for more resources on the Virginia earthquake?  Check out the PAESTA website as well.

The Penn State Brandywine station is the second line in from the left (marked by the light green triangle above)

The Penn State Brandywine station is the second line in from the left (marked by the light green triangle above)

Screen Shot 2014-04-02 at 1.03.47 PM

So, let’s revisit the original question… has Tyler Arboretum ever experienced an earthquake?  You bet!  We have in the past, and we certainly aren’t done feeling the Earth move under our feet….


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The Pink Hill Serpentine Barren of Tyler Arboretum – a Rare Gem

Tyler Arboretum is filled with all sorts of unique natural features to explore. Sure, there is a lot of excitement building up to the treehouses reopening this spring, and the last of the snow and ice has melted away from the multiuse trail. But let’s not forget about the gems that are outside of the fence and available for exploration – like the Pink Hill Serpentine Barren (warning – fascinating geologic knowledge coming your way!).

The beautiful "Phlox subulata" from Tyler Arboretum's Pink Hill. Image provided by Laura McPhail.

The beautiful “Phlox subulata” from Tyler Arboretum’s Pink Hill. Image provided by Laura McPhail.

You may have already traveled across this site, certainly if you have hiked along the Pink Hill Trail. It is not a coincidence that the trail has this name, for starting this month, you will see the native wildflower Phlox subulata blooming in beautiful pink. This moss phlox does very well across this grassland – which is fascinating scientifically, as native grasslands in the northeastern United States are uncommon.

But wait – there’s more! Even more fascinating is the fact that this grassland is really a serpentine barren, the last of its kind in Delaware County! What is a serpentine barren, you may ask? Let’s start with serpentine… Serpentine is a group of related minerals that are relatively soft and feel greasy to the touch that together form a metamorphic rock called serpentinite. These minerals typically have the chemical formula X2-3Si2O5(OH)4  where X = Mg, Fe2+, Fe3+, Ni , Al, Zn, or Mn. There are two main forms of serpentine – antigorite represents the more solid forms, and chrysotile represents the fibrous forms.  Serpentine is created from extremely high temperatures and pressures deep in the Earth (but still just at the upper mantle layer) at plate tectonic boundaries.  In fact, it is not uncommon to have existing olivine and pyroxene minerals in an igneous rock called peridotite be subjected to water that becomes superheated when ocean crust is near tectonic boundaries (the incredible chemical reactions that happen because of hot fluids – pretty incredible!).

Where might you find serpentine now (at least exposed at the surface)?  This quote from a 1903 publication shows that scientists have had a fascination with mapping serpentine deposits for some time.

“Parts of Montgomery, Delaware, Chester and Lancaster Counties, Pennsylvania, are noted from a geologic standpoint for the presence of outcrops of serpentine rock. This rock formation is confined to the district southwest of the Schuylkill River, extending in a somewhat southwestward direction into Maryland, near the lower Susquehanna River. The largest outcrops near Philadelphia occur in the neighborhood of Lima, Delaware County, at Newtown Square, at places north and southwest of West Chester, while isolated patches exist south of Bryn Mawr and northwest of Media. There seems no doubt but that all of the serpentines in southeast Pennsylvania are altered igneous rocks, either pyroxenites or peridotites.” — John Harshberger, The Flora of the Serpentine Barrens of Southeast Pennsylvania, Science, volume 18, number 454, page 339-343. Published September 11, 1903.

Serpentine rock (serpentinite) is throughout eastern North America in isolated rock units from Canada down to Alabama (as well as out west, but I’ll just stick with the eastern exposures); however, the most diverse and botanically-significant outcrops are in southeastern Pennsylvania and northern Maryland (see State Line Serpentine Barrens), including Delaware County.  The eroded serpentinite forms the foundation for a soil that is called – you guessed it – serpentine.  And when you hear the phrase “serpentine barren,” this typically refers to not just the exposed and eroded serpentinite but also to the ecosystem that has formed and established in these shallow soils.  You see, Eric Jones from Cal Poly explains “that serpentine soil carries the unique chemical composition containing high amounts of magnesium and low amounts of calcium. The pH of the soil greatly varies, ranging from 6.1 (slightly acidic) to 8.8 (slightly basic). In many cases heavy metals, such as chromium, nickel, and iron, are present and give the soil its red color. Serpentine soil is typically a shallow and rocky, not suitable for retaining water. These conditions inhibit plants from developing deep roots, also making serpentine soils highly vulnerable to erosion. The abnormal chemical composition of serpentine also restricts the growth of normal plant habitats, instead supporting its own unique flora which have adapted over time.”

DID YOU KNOW… Nearly half of the serpentinite found in North America is located in California, making it a natural choice for the state rock.

I hope I haven’t bored you with the science behind serpentine and serpentine barrens, but here is why serpentine barrens are important, and why we should care.  They contain very unique biological communities that are not found elsewhere on our planet.  Many of the key species in these communities are threatened and in danger of going extinct – and one of the causes of the endangered status is human development and encroachment.  But human activity can also protect, conserve, and educate others about this really special place right here at Tyler Arboretum.

One reason I’m excited about Tyler’s Pink Hill Serpentine Barren as it provides an excellent site for me to bring my students to visit. There are not many geological areas in this immediate area that are safe for us to explore (too many outcrops are along a busy road or difficult to get to), and being able to take students to this local site will help them learn more about their own space and place in the local environment. By showing students the serpentine barren, I can help students learn more about the ground on which they live, work, and go to school.   I can also introduce students to different time scales, differentiating between what happens in human timescales versus geologic time (millions of years). I think the serpentine barren is an excellent site underutilized by teachers and students, and I will be making sure that my courses explore the history and geological significance of this incredibly unique site.

To view the hill and meadow known as Tyler Arboretum’s Pink Hill Serpentine Barren, start on the multiuse trail and exit Gate 7 in the deer enclosure fence. Walk across Painter Road, then cross Dismal Run stream via two bridges to view Tyler’s Chestnut Nursery and hilltop views of the Arboretum and Pink Hill.

To read more on this subject, check out the publication Pink Hill Serpentine Barrens Restoration and Management Plan, by Roger Latham (a free PDF downloadable from Tyler Arboretum’s website).

AND, if you are STILL interested in learning more, you should mark on your calendar a speaking engagement by Roger Latham.  He will speak at an open meeting about Pink Hill and the importance of its preservation at the Middletown Township Land Conservancy Meeting on April 22, 2014 at 7:30 p.m. at the Middletown Township Building, located at 27 N. Pennell Road in Lima, PA.


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A Visit to the Pennsylvania Chapter of The American Chestnut Foundation

DSCN3293Many of you are aware that I am a faculty member at Penn State Brandywine, right across the way from Tyler Arboretum.  Several times a year, I make the journey to the Penn State University Park campus in State College – which also happens to be the home of the Pennsylvania Chapter of The American Chestnut Foundation (PA-TACF)!  I have volunteered at Tyler’s chestnut nursery, and I’ve helped bag the harvested chestnuts.  Now, I know to where those chestnuts are shipped!

The PA-TACF office is in the Forest Resources Laboratory Building.  On a sunny/windy morning, I headed over to meet with Chapter Administrator Stephanie Bailey.  Stephanie was incredibly kind to allow me to spend a couple of hours with her, and she took me around their facilities and over to the chestnut orchards on campus.  Stephanie was incredibly knowledgeable about the program and the activities of the chapter – for example, did you know that Tyler is one of more than 150 (probably closer to 200!) chestnut orchards for the PA-TACF???

I learned that the hybrid chestnut seed orchard at Penn State began in June 2002 as a partnership between the PSU College of Agriculture, PSU School of Forest Resources, and The American Chestnut Foundation.  The orchard began with 257 three-month old seedlings, with more being added each year.  There are now three orchards established in State College.

I’ll let the photos below tell the story of my visit!

The refrigeration units that house the chestnut seeds we harvest from Tyler.

The refrigeration units that house the chestnut seeds we harvest from Tyler.

I even found a bag with a "Tyler" label!

I even found a bag with a “Tyler” label!

Then it was out to one of the greenhouses to see the seedlings start their growth

Then it was out to one of the greenhouses to see the seedlings start their growth.

Then, it was time to head out to the orchards!  For those of you on top of the classification for the backcross breeding program, the chestnut trees at Penn State are BC3F2.

A beautiful view across the orchard.  You can see one of the plots, where 150 trees from each "family" (cross) are planted to ensure that at least oen of them is homozygous for blight resistance.

A beautiful view across the orchard. You can see one of the plots, where 150 trees from each “family” (cross) are planted to ensure that at least oen of them is homozygous for blight resistance.

Rows and rows of tubes to protect the seedlings put in place by volunteers (and at times, knocked down by groundhogs!).

Rows and rows of tubes to protect the seedlings put in place by volunteers (and at times, knocked down by groundhogs!).

I had so much fun going around and seeing the work being done by PA-TACF in State College.  Stephanie was an excellent host and was so enthusiastic!  She is the perfect person to represent PA-TACF, and I know our Tyler chestnuts are in excellent hands!

And feel free to view even more photos from my trip!



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Scientific American reports on the American Chestnut Tree

Work will not begin at the Tyler Arboretum chestnut nursery for a few more weeks, but you can get a head start on learning about the American Chestnut Tree in this month’s issue of Scientific American.  This magazine does a great job writing about science topics without the jargon for a non-science audience.

The website for the March 2014 issue of Scientific American only gives a short preview for William Powell’s article titled The American Chestnut’s Genetic Rebirth (A foreign fungus nearly wiped out North America’s once vast chestnut forests. Genetic engineering can revive them), with the full article available in the print issue.  But there is a wonderful web article by Ferris Jabr available for free titled A New Generation of American Chestnut Trees May Redefine America’s Forests (Before an exotic fungus nearly wiped them out in the late 1800s, abundant chestnut trees shaped the forest ecosystem, providing food and shelter for numerous other species. In coming decades Chestnut trees engineered to battle the fungus could restore these lost relationships).

In diving deeper into the archives of Scientific American, I discovered that this magazine has been reporting on the American Chestnut since at least 1855, with an article titled Grafted Chestnut Trees.  Additional articles include:

1906 – A Disease Which Threatens the American Chestnut Tree

1912 – The Chestnut Tree Blight

1913 – Fighting the Chestnut Bark Disease

1915 – Chestnut Blight Poisoning

1990 – Chestnut Blight

2009 – Chestnut Trees Return to the Eastern U.S.

2009 – Chestnut’s Revival Could Slow Climate Change (*full article online!)

I find it interesting that there were articles in the early 1900′s, and then a large gap in reporting on the American Chestnut Tree for several decades.  It is good that the chestnut is back in the news – we still have so much more to learn, and much more work to do!

I hope to see you in Tyler’s chestnut nursery soon!


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Tyler Arboretum is an IBA (Important Bird Area)

Photos at Tyler on 12/18/13

Photo on the front of the Visitor Center at Tyler Arboretum

The more time I spend going through Tyler Arboretum’s website, the more interesting “nuggets” of information I come across.  For example, on the Tyler At A Glace page under the About Us section, there is a bullet point under the Natural Lands section that reads:

Tyler is recognized as an IBA (Important Bird Area) by the National Audubon Society and maintains an active Bluebird Nest box program with 47 monitored and maintained boxes.

I immediately became curious – what does it mean to be an IBA?  What does this designation mean for birds – and for Tyler?  My Google searching led me to find the answers I was looking for!

As stated on Tyler’s website the National Audubon Society oversees the Important Bird Areas Program.

Important Bird Areas, or IBAs, are sites that provide essential habitat for one or more species of bird. IBAs include sites for breeding, wintering, and/or migrating birds. IBAs may be a few acres or thousands of acres, but usually they are discrete sites that stand out from the surrounding landscape. IBAs may include public or private lands, or both, and they may be protected or unprotected.  –  from What Is An IBA?

The IBA Program has an impressive, interactive website that allows the user to search by state and/or through an interactive map.  I quickly found the information for Pennsylvania’s Important Bird Areas Program.

Formed in 1996, Pennsylvania developed the first statewide Important Bird Area (IBA) program in the country. A group of scientific advisors (known as the Ornithological Technical Committee) has identified over 80 IBA sites encompassing over two million acres of Pennsylvania’s public and private land. These areas include migratory staging areas, winter roost sites and prime breeding areas for songbirds, wading birds, and other species. Pennsylvania is making an important contribution to the conservation of bird habitat in the western hemisphere. Penn’s Woods are critical to many interior forest birds, providing nesting habitat to 17% of the world’s Scarlet Tanagers and 9% of the Wood Thrushes. By focusing attention on the most essential and vulnerable areas, the IBA program helps to promote proactive habitat conservation, benefiting birds and biodiversity. Audubon Pennsylvania works with a multitude of partners across the Commonwealth to advance the conservation of Important Bird Areas. — from PA’s Important Bird Areas Program

I was then able to drill down and found Tyler Arboretum on their map as part of a larger area designated as the Upper Ridley/Crum Site.

Site Description
The Upper Ridley/Crum Important Bird Area includes Ridley Creek State Park, Tyler Arboretum and a vast expanse of primarily private land north of Route 3. Other publicly-accessible sites include Willistown Township’s Okehocking Preserve (Route 3 and 926), and several preserves owned by the Willistown Conservation Trust.

Ornithological Summary
The site is significant for its use during migration and the nesting season. As a large patch of green in a fully suburbanized region, the IBA acts as a vital stopover site for many species of neotropical migrant songbirds. Several woodland species of concern stay for the summer and nest within the IBA, including Kentucky Warbler, Hooded Warbler and Wood Thrush. Grasslands and agricultural fields in the IBA provide stopover habitat for Bobolinks and nesting habitat for a few Eastern Meadowlarks.

The Audubon Pennsylvania website has even more information specific to Pennsylvania about the IBA program, along with some helpful responses to IBA FAQs and a complete, detailed site profile for Upper Ridley/Crum.

My investigation in to the IBA program has given me an even greater appreciation for the role Tyler plays in biodiversity and conservation of our avian population.  Now I need to work on my bird identification skills to see if I can spot some of these critical species!


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