Posts Tagged ‘trees’

Nature Stories: Snowflake


Thursday, January 3rd, 2013
Snowfall in Vermont 12/27/12

Snowfall in Vermont 12/27/12

Anyone who has looked closely at a snowflake under a magnifying glass, or even with their naked eye, has an appreciation for the intricacy and delicacy of these frozen ice crystals that descend from the sky.  Exactly how do they form and why do they assume the shapes that they do?

Snowflake © Kenneth G. Libbrecht

Snowflake © Kenneth G. Libbrecht

According to physicist Kenneth Lebbrecht, in his book The Snowflake: Winter’s Secret Beauty, snowflakes and snow crystals are made of ice. As its name implies, a snow crystal consists of a single crystal of ice.  Snowflake is a general term that includes all shapes and combinations of snow crystals.  A snowflake can be a single snow crystal, or a conglomerate of crystals.

A snow crystal is not a frozen raindrop.  When raindrops freeze, they are referred to as sleet; the individual particles of ice lack the intricate patterns of snowflakes.  Rather, snow crystals form when water vapor in the clouds condenses directly into ice. As more vapor condenses, the ice crystal grows and develops, creating elaborate patterns.

Snowflake © Kenneth G. Libbrecht

Snowflake © Kenneth G. Libbrecht

There is a sequence of events in the formation of a snow crystal.  Evaporation from the ocean, lakes and streams, as well as the transpiration of plants and the expiration of animals puts a large amount of water vapor into the air.  When a mass of air cools, the water vapor it contains condenses out of it.  In summer, when this occurs next to the ground, we refer to the condensed water droplets as dew. When the air high above the ground is cooled, the water vapor condenses onto particles of dust, forming clouds full of water droplets.  In winter, the individual water droplets start to freeze around 14 degrees Fahrenheit. They don’t all freeze at once; gradually the water droplets surrounding the particles of ice evaporate into water vapor which then condenses onto the ice crystals, growing snow crystals.


Snowflake © Kenneth G. Libbrecht

Many snow crystals begin as hexagonal prisms – flakes with smooth facets, or sides, arranged in a hexagonal shape.  “Branches” then sprout at each of the six corners of this hexagonal crystal and as the surrounding water vapor condenses on them, they grow. Because the entire crystal passes through the same climatic conditions, the branches tend to grow in a similar pattern at a similar rate, creating the six-pointed star-shaped crystal, or stellar dendrite, that we are familiar with.  Many shapes, including columns, plates and needles, are formed.  Humidity, and particularly, temperature, affects the pattern of growth.  Snow crystals tend to form simpler shapes when the humidity is low, and more complex shapes at higher humidities. Even so, the majority of snowflakes are not symmetrical.  Within a given cloud, different snowflakes are blown in different directions, encountering different temperatures, which results in slightly different shapes.  Thus, no two snowflakes are identical.

Snowfall © Mary Holland

Snowfall © Mary Holland

Throwback: Sappy Holidays – The Brazilian Pepper


Friday, December 21st, 2012


Brazilian Pepper

Brazilian Pepper © Jungle Pete


Sappy Holidays – The Brazilian Pepper Originally Posted 12/19/2011 by Jungle Pete

As a child growing up in South Florida I had the good fortune of living on a 10-acre rural sanctuary for primates, operated by my parents. The property was covered with native Slash Pines (Pinus elliotti), Cabbage Palms (Sabal palmetto) and Live Oaks (Quercus virginiana), but was persistently threatened by the noxious weed of a tree known as Brazilian Pepper (Schinus terebinthifolis). As a human primate, I had far more freedoms than the other inhabitants and like a modern day Jungle Boy I would often take to the trees and explore. There were times when the property had become so overgrown with what some call “Florida Holly” that I could ascend into the canopy of the pepper trees and climb from tree to tree for several hundred feet.

The problem for a kid is you end up with ripped up jeans and sticky sap all over you, as well as the possibility of a poison ivy-like rash. The problem for the ecosystem is the highly invasive tree has spread throughout South Florida, establishing dense monocultures where little else grows.

Brazilian Pepper was introduced to Florida sometime in the mid-1800s as an ornamental. It grows natively in Brazil, Argentina and Paraguay. In Florida it flowers from September through November and by December has fire engine red berries that express a festive spirit around the holiday season, when Florida’s native hollies had already lost their rosy red fruit. Certainly the intent upon introduction was not malicious, but 160 years later the tree is so pervasive we could easily deck the halls with boughs of pepper if only it were legal to transport it.

Fortunately the tree is not cold tolerant. Unfortunately it produces an abundance of berries that are perfect holiday snacks for birds and mammals. They digest them and poop them elsewhere with homemade fertilizer.

Every year at this time, the sight of the bright evergreen leaves and candy cane red pepper berries brings me back to my days on the sanctuary, either climbing in the trees or hacking them down with machete or chainsaw.

I learned long ago that wherever I am for the holidays, I am perfectly content to celebrate it by enjoying it with native style and tradition. This year I’ll be enjoying the sun, the sand and berryless hollies. Happy Holidays.

Jumping Oak Galls


Wednesday, December 19th, 2012
Jumping Oak Galls

Jumping Oak Galls © Julie Craves

Jumping Oak Galls by Julie Craves

A move to a new house has been responsible for my lack of productivity here the last few months. Now that we are settled in, we are anxious to get to know our large property. We have eight acres of wet woods, and while my bark identification skills are serviceable, I’ve been spending more time looking down at the ground to unlock some of the secrets of the forest we will now stewards.

Many of the mature trees are Black Cherry, Bur Oak, and Swamp White Oak. I noticed that many of the fallen oak leaves were pocked with dozens, if not hundreds, of round lesions, each the size of a pinhead. On the uppersides of the leaves, they looked just like pimples. On the underside, each lesion was a shallow pit that was either empty or had a tiny nodule nestled in it.

Those nodules are galls, created by very minute wasps in the genus Neurotarus. They’re known as jumping oak galls, because when the galls detach from the leaf and fall to the ground, the wasp larva inside will sometimes wiggle around and cause the gall to move. The fully developed wasp larvae will overwinter in their galls on the ground. Galls that remain on the leaves are probably doomed – they’ll either dry up and die, will expire because they have been parasitized or their galls have been invaded by insect inquilines, interlopers that feed on the gall tissue.

If all goes well, these galls will produce the all-female generation. Neurotarus wasps, like many of the others in their family, have elaborate life cycles that include alternating asexual and sexual generations.

Members of this family of wasps are quite host-specific, usually attacking only one or a few species of oaks; none use hosts in both the red and white oak groups. All the gall-bearing leaves I found were white oaks, with none on the plentiful red oaks present on the upland parts of the property.

Spots of Tar


Wednesday, December 5th, 2012

Silver Maple Tar Spots © Julie Craves

Spots of Tar  by Julie Craves

In the upland area of our new property, oaks and cherries give way to maples. Judging from the fallen leaves, most are Silver Maples. In my search for other species, I noticed that many of the fallen maples leaves were disfigured by black blobs. I had noticed a more severe outbreak these spots on maple leaves still on the trees at my urban field site earlier in the year. These distinctive spots are caused by fungi in the genus Rhytisma, commonly (and appropriately) called tar spot disease.

The fungi overwinter in the spots, which are known as stromata, on fallen leaves especially if they are in a damp, protected location. Spores burst forth from the spots in the spring, coinciding with new leaf emergence on nearby maple trees. The wind-dispersed spores can then infect new leaves. Infections begin as yellow spots that eventually evolve into the tar-like blobs we see in autumn.

Generally, tar spot doesn’t do much harm other than cosmetic, even though in the last several years many maples have had dramatic infestations in the upper Midwest. A particular species of Rhytisma infects Silver Maples, while another, non-native species that favors introduced Norway Maples has been increasing in the northeastern U.S. the last decade or so. This explains the sparsely-blotched Silver Maple leaves on my property versus the heavily-splotched Norway Maples at my urban field site; the fungus that infects the latter tends to create more spots that congeal into large patches.

It has been speculated that tar spot on Norway Maples is on the rise because of cleaner air quality (the fungi are thought to be sensitive to pollution). And recent research has shown that leaves infected with tar spot decay more slowly than uninfected leaves, which may indicate that there is a more subtle effect of this disease on nutrient cycling or soil conditions. These are interesting interactions and synergies to study, especially given the ubiquity of Norway Maples in urban areas, where soils are subject to so much alteration already.




A Drunken Spruce


Monday, October 29th, 2012
Black Spruce

Black Spruce © Lisa Densmore

Location: Delta Clearwater River, Alaska

While fly fishing on the Delta Clearwater River, I thought it curious that black spruce (Picea mariana) was the dominant tree along the riverbanks for most of our 20-mile float trip. In my native Adirondacks in upstate New York, 4,100 miles east of the Delta Clearwater River, black spruce is also relatively common. Though Alaska and New York are so completely different, I realized that boreal forests throughout North America can be similar regardless of location. In fact, black spruce can be found across Canada, from Newfoundland to British Columbia, and in Minnesota. It is the provincial tree of Newfoundland and Labrador.

This spindly conifer is sometimes called “drunken spruce”, perhaps because they often lean against their neighbors or fall over, though the reason is not firewater but a shallow root system. Despite a propensity for tilting, they are well adapted for the cold, moist regions in which they reside. They need shallow roots to stay above the perma-frost layer, at least in the northern parts of their range. Their short branches deter heavy accumulations of snow. Even so, the lowest branches will take root when deep snow bends them to the ground creating a ring of younger trees around an older one. As a result, black spruce form homogeneous groves in wet, boggy areas, which was the case where I was fishing.

Black spruce is the unshaven backwoods brother of prissy white spruce. It looks unshaven with black hairs on its twigs and its thin, untidy appearance. It also has shorter needles, smaller rounder cones and a preference for wetter low-lying areas than white spruce does.

To me, the black spruce along the Delta Clearwater River formed a scraggly barrier. At first I would have preferred a more diverse view, but the longer I fished and pondered their presence, the more I appreciated their ability to grow in what would most certainly become inhospitable Arctic weather only a few short weeks after my departure.

All We Have To Fear…


Monday, October 29th, 2012

All We Have To Fear © Jungle Pete

All We Have To Fear… by Jungle Pete Corradino 

Arachnids with web spinning architectural prowess
Long-legged daddies with eight legs more or less
Brown furred mammalians with leathery wings
These are a few of my favorite things

Snakes striped with colors that will kill-a-fella
Turtles accused of passing salmonella
Poisonous ivy that desperately clings
These are a few of my favorite things

Aquatic finned creatures with razor sharp gnashers
Thundering, bumbling, honeycomb crashers
Well armored grubbers with nine banded rings
These are a few of my favorite things

When people fear them
When they kill them
This makes me mad
Please would you respect my favorite things
And then I don’t feel so bad

Remarkable Nature Places: Beidler Forest


Thursday, October 11th, 2012
Beidler Forest

Photo courtesy of Mark Musselman, Audubon South Carolina

Remarkable Nature Places: Beidler Forest

The National Audubon Society’s Francis Beidler Forest, located in Four Holes Swamp, SC – less than an hour from Charleston – contains within its 16,000+ acres the largest remaining stand of virgin Bald Cypress and Tupelo Gum swamp forest left anywhere in the world. Here, 1,000-year-old trees and native wildlife abound in a pristine sanctuary that has been untouched for millennia.

Beidler Forest

1,000 year old tree Photo courtesy of Mark Musselman, Audubon South Carolina

A 1.75-mile self-guided tour along the boardwalk trail allows visitors the chance to safely venture deep into the heart of the swamp… to experience the peace and serenity that have characterized the area for centuries… to hear the sounds of bird and bug and breeze that have echoed through the trees for ages… to take a relaxing and informative walk back into time… to see a swamp the way nature intended.

A swamp is a flooded forest. There are many different types of swamps, but one thing they all have in common is trees in the water, for at least part of the year.

Beidler Forest

Swamp Photo courtesy of Mark Musselman, Audubon South Carolina

Bald Cypress

Largest in U.S. — 17 feet in diameter, Cat Island, LA

Largest at Beidler Forest — 10 feet in diameter

Oldest Known — 1600 yrs, Black River Swamp, NC

Oldest Known at Beidler Forest — 1500 yrs (2nd oldest in the world)

Beidler Forest

Hollow Tree Photo courtesy of Mark Musselman, Audubon South Carolina

Tupelo Gum

Largest in the U.S.  8 feet in diameter, Kinder, LA

Largest at Beidler Forest 5 feet in diameter

Oldest Known at Beidler Forest?? Most over 18’’ are hollow

Beidler Forest

Goodsen Lake Photo courtesy of Mark Musselman, Audubon South Carolina

Cypress Knees

Despite much research, cypress knee function remains a mystery. One thing is certain – knees grow in response to the presence and depth of water. A Bald Cypress growing on dry ground will have only a few small knees, if any. One in deeper water will have taller knees. Generally, the trend we find is the older the tree, the more gnarly the knee.

Beidler Forest

Cottonmouth Photo courtesy of Mark Musselman, Audubon South Carolina

Beidler Forest

American Alligator Photo courtesy of Mark Musselman, Audubon South Carolina

NO turtle can leave its shell.

NO venomous lizards exist in South Carolina.

NO venomous snakes with lengthwise stripes in South Carolina.

NO such thing as a Hoop Snake or Pilot Rattlesnake.

NOT all snakes in the water are venomous.

• Milk snakes do NOT milk other animals.

• Coachwhip snakes do NOT chase and whip people.

• Copperheads are NOT female rattlesnakes.

• Of 38 snake species in South Carolina, ONLY 6 are venomous!

• Glass Snakes are legless lizards and should be called Glass Lizards

Beidler Forest

Deer fawn Photo courtesy of Mark Musselman, Audubon South Carolina

How would you have described a swamp BEFORE your visit here? Look around. Smell the air. Notice the lack of bugs? Is the swamp what you expected?


“Buggy” Mosquitoes prefer not to lay eggs in flowing water.
“Snakey” Most snakes prefer to sit still on a log, and of all the water snakes, only the cottonmouth is venomous.
“Gatory” Alligators prefer deeper water and sunshine, not the shallow and shadowy channels in a swamp.
“Smelly” Abundant plant life acts as an air filter. Plus, periodic floods help to flush decaying material.
“Muddy” The swamp floor is mostly hard-packed sand.
“Polluted” The water that flows through Beidler Forest is some of the cleanest in South Carolina due to miles of filtration and percolation.
“Evil” Walking through a swamp is a peaceful and relaxing activity.
“Spooky” No monsters or mythical creatures have been reported…yet.
Beidler Forest

Prothonotary Warbler Photo courtesy of Mark Musselman, Audubon South Carolina

Since 1979, Breeding Bird Censuses have been conducted on two 20-acre plots on the sanctuary. One is located in the old-growth stand, the other in woods cut in the 1960’s. Routinely, the old-growth plot has been found to contain some of the highest densities of nesting songbirds per acre for forested habitats in the eastern U.S.

The diversity of tree species, the variety of tree ages, and the multi-layered structure of the forest cover found in the old-growth stand all work together to provide spectacular habitat for birds of many species.

Beidler Forest

White Ibis Photo courtesy of Mark Musselman, Audubon South Carolina

That’s the good news. The bad news is that, despite their nesting success here, many species are in decline due to habitat loss in their summer breeding grounds, along their migratory routes, and in their Central and South American wintering grounds.

Beidler Forest

Photo courtesy of Mark Musselman, Audubon South Carolina

• Canoe and Kayak Tours – Accompanied by one of our trained guides, let us take you through the heart of the swamp on a peaceful paddle for either a 2- or 4-hour trip. Bring the whole family to experience close encounters with wildlife. It’s a wonderful trip for great photography!

• Night Walks – See the forest under a new light. The swamp is particularly active when the sun goes down. Walking beneath a moonlit sky guided by an Audubon naturalist, we listen to the music of the night and search for nocturnal animals.

• Other Walks and Events – Scattered throughout the season we have a slew of great activities including bird walks, swamp stomps, flower walks, and social events. Ask the staff at the visitor center for more information.

Barred Owls Photo courtesy of Mark Musselman, Audubon South Carolina

Beidler Forest

The boardwalk Photo courtesy of Mark Musselman, Audubon South Carolina

Did You Know: Petrified Forest National Park


Thursday, October 11th, 2012
Petrified Forest National Park

Photo Courtesy of Petrified Forest National Park, Arizona

Petrified Forest National Park

34.910147° N 109.807377° W

Petrified Forest National Park, located on the Colorado Plateau in northeastern Arizona, is known for its Late Triassic fossils. Here you’ll find native Arizona grassland, mesas, buttes, rivers, springs, and wildflowers. Over 13,000 years of human history and culture can be found here. Best known for globally significant Late Triassic fossils, the park attracts many researchers. Geologists study the multi-hued Chinle Formation. Archeologists research over 13,000 years of history. Biologists explore one of the best remnants of native Arizona grassland. Air quality is an ongoing study in the park. Discover your own passion at Petrified Forest!

Petrified Forest National Park

Photo Courtesy of Petrified Forest National Park, Arizona

Petrified Forest National Park

1 Park Road
P.O. Box 2217
Petrified Forest, AZ 86028

(928) 524-6228

Petrified Forest National Park

Photo Courtesy of Petrified Forest National Park, Arizona

Did you know? Petrified Forest National Park

Petrified Forest National Park has one of the most diverse collections of prehistoric pottery fragments in the Southwest.

The ecosystem at Petrified Forest National Park is not a desert. It’s one of the largest areas of intact grassland in the Southwest.

Petrified Forest National Park is the only national park unit to protect a section of Historic Route 66!

In addition to the world-class fossil record at Petrified Forest National Park, archeological resources are so abundant and so significant that they could stand alone within their own park!

On clear days in the Southwest, especially on crisp, cold winter days, you can see landscape features almost 100 miles away!

Petrified Forest National Park

Photo Courtesy of Petrified Forest National Park, Arizona



A bird list can be found here.

Petrified Forest National Park

Pronghorn Photo Courtesy of Petrified Forest National Park, Arizona


Coyote, Gray Fox, Swift Fox, Bobcat, Mule Deer, Pronghorn, Ringtail, Raccoon, Badger, Striped Skunk, Western Spotted Skunk, Black-tailed Jackrabbit, Desert Cottontail, Desert Shrew, Pallid Bat, Townsend’s Big-eared Bat, California Myotis, Fringed Myotis, Yuma Myotis, Canyon Bat, Porcupine, Gunnison’s Prairie Dog, White-tailed Antelope Squirrel, Spotted Ground Squirrel, Rock Squirrel, Botta’s Pocket Gopher, White-throated Woodrat, Stephens’ Woodrat, Ord’s Kangaroo Rat, Silky Pocket Mouse, Northern Grasshopper Mouse, Brush Mouse, Canyon Mouse, White-footed Mouse, Deer Mouse, Pinon Mouse, Western Harvest Mouse, House Mouse

Eastern Collard Lizard

Eastern Collard Lizard © Rod Planck, Photo Researchers, Inc.

Reptiles and Amphibians:

Tiger Salamander, Great Plains Toad, Red-spotted Toad, Woodhouse’s Toad, Couch’s Spadefoot, Mexican Spadefoot, Plains Spadefoot. Reptiles are Plateau Striped Whiptail, Eastern Collared Lizard, Common Lesser Earless Lizard, Greater Short-horned lizard, Sagebrush Lizard, Plateau Lizard, Common Side-blotched Lizard, Ornate Box Turtle, Glossy Snake, Rattlesnake, Nightsnake, Common Kingsnake, Milksnake, Pai Striped Whiptail, New Mexico Whiptail, Striped Whipsnake, Gophersnake, Black-necked Gartersnake

Colorado Pinyon Pine

Colorado Pinyon Pine © Lance Beeny


Two needle Pinyon/Pinyon Pine, One Seed Juniper, Little Utah Juniper, James Narrow Cottonwood, Fremont Cottonwood, Narrow Leaf Willow, Coyote Willow, Goodding’s Willow, Russian Olive, Tamarisk, Nevada Jointfir, Torrey’s Jointfir, Siberian Elm


A wildflower list can be found here.

Petrified Forest National Park

Photo Courtesy of Petrified Forest National Park, Arizona


Petrified Forest National Park

Photo Courtesy of Petrified Forest National Park, Arizona

Throw Back Thursday: Abscission and Marcescence in the Woods


Wednesday, October 10th, 2012

Throw Back Thursday: Abscission and Marcescence in the Woods by Kent McFarland

Originally Posted 11/9/2009

While on a recent hike in the hills of Vermont, I noticed that some trees had lost their leaves while others still had golden brown leaves all over them. It seemed that all of the Red Oak and the American Beech trees still had a nearly full canopy, while the Sugar Maple along the old woods road were completely naked.

trees woods

Foliage © Kent McFarland

I snapped a photo of it so I could do a bit of research at home. It turns out that Oak and Beech trees have marcescent leaves. Marcescence is when a plant part dies but is not shed. In the photograph you can see that the Sugar Maple trees in the foreground along the old carriage road have completely shed their leaves, while the Beech trees on the hillside are still fully loaded.

A tree is full of vascular cells that transport water and sap from root to leaf. As the amount of sunlight decreases in autumn, the veins that transport sap into and out of the leaves slowly close. A layer of cells, called the abscission layer, develops at the stem base. The leaf falls off when this layer is completely formed.

Oak (Quercus), Beech (Fagus) and Hornbeam (Carpinus) are an exception. The separation layer doesn’t fully allow the leaves to detach. That’s why most of their dead leaves remain on the tree through winter until the wind rips them away. But one has to wonder what advantage this would have for the trees. It may be that it deters foraging of young buds and branches by deer. If there are a lot of dead leaves on the ends, it may not be as palatable. It may aid in protecting the tree from water or temperature stress during the winter. Or, perhaps it is a left over ghost from the past that is now neutral, neither hindering nor helping the species prosper. Whatever the reason, in late fall you can easily see the forest for the oak and beech trees.

Trees: Turn Red or You’re Dead


Wednesday, October 3rd, 2012
trees Foliage Nature

Fall Foliage © Kent McFarland

Throw Back Thursday Originally Posted 10/18/11 Notes from the Field – Trees: Turn Red or You’re Dead by Kent McFarland

I have often wondered why on one hillside the trees have muted fall colors, while nearby on another they are radiant red. Recent research might be shedding some light.

There are four basic colors in fall leaves and a different pigment produces each. Xanothophylls is responsible for yellow, carotenoids for orange, tannin for brown and anthocyanids create the red and purple tones.

During the growing season green chlorophyll in tree leaves is broken down by sunlight and constantly replenished. As day length decreases the abscission cells, a special layer at the leaf-stem junction, divide rapidly and slowly block transport of materials. As abscission begins, a chlorophyll production wanes and eventually stops.

As the green chlorophyll breaks down without replacement we begin to see the underlying orange carotenoids and yellow xanthophylls. These pigments help capture light energy during the growing season. But unlike yellow and orange pigments, red anthocyanins are made during fall leaf senescence. It is manufactured from sugars found in the leaf. They produce greater amounts during cooler nights and sunny days. When a hard freeze comes along, production ends.

Why would a tree use energy to make a pigment in a leaf that is about to die and fall off? William Hoch, a biologist at Montana State University, found that if he genetically blocked anthocyanin production, the leaves were much more vulnerable to fall sunlight damage, and so sent less nutrients to the plant roots for winter storage before the leaf fell. The tree was not able to recuperate as much energy back from the leaves it grew earlier in the year.

University of North Carolina at Charlotte graduate student Emily Habinck found that in places where the soil was lower in nitrogen and other important elements, red maple trees produced more anthocyanin in the leaves. Apparently trees growing in more stressful environments invest in more anthocyanin, which allow them to recover more nutrients that are stored in the leaves before they fall.

Bright red leaves under a clear blue sky are spectacular to see. But what is beauty to us, is simply survival to a tree.