Saturday, January 28, 2012

Giant Willow Aphids - Winter In The Willow

We don't see many insects this time of year.  Yet, here are some Giant Willow Aphids hanging out on the Curly Willow in our backyard, in spite of the cold and snow.
  These few are remnants of a big willow aphid colony that was here until a few weeks ago.  Most of them grew wings and went elsewhere to overwinter as adults.  Honestly, the ones that are left look rather dead... I even took a few into the house to try to thaw them out... unsuccessfully.  Maybe the cold and exposure had gotten to them, or maybe I just picked the wrong ones to try to revive.
   Giant Willow Aphids are large (as aphids go), grey aphids with a dorsal tubercle which look somewhat like shark fin.
Giant Willow Aphid - Tuberolchnus salignus
In the late fall, or early winter, the adults grow wings like the one pictured in the background of the photo below.

Here is a photo of the aphid colony in the beginning of December.
Notice a few of them have wings.
Colony of Giant Willow Aphids - Tuberolchnus salignus
I went out one frosty morning to get a close-up picture showing frost crystals on the willow branch opposite the aphids.
Frosty willow aphids
I thought a photo showing the ice crystals would illustrate the willow aphid's cold tolerance.  Despite the hard frosts, cold nights, and even some snow.... most of the aphids grew wings and left.
   Even if these remaining ones are dead, the aphid's cold hardiness is on display, because wherever the others went, it's just as cold there...just not as exposed to the wind, rain, and rapid temperature fluctuations.

   When  I first noticed the aphids feeding on our willow, the colony was quite small... see the picture below.  These aphids are reported to only reproduce parthenogenetically - that is the female gives birth to a genetically identical daughter aphid through asexual reproduction.  That means the aphids in large colony I photographed Dec 1st are all clones...genetically identical subdivisions.
   Notice the aphids were being tended by many ants which were furiously defending their honeydew supply against an onslaught of intruding mosquitoes and other insects. I counted about a dozen diptera in this photo. There is also a small parasitic wasp in the right side of the picture approaching on a branch.

  I actually noticed the aphid colony when I was taking a closer look at a cloud of insects swirling around the in the willow.  This swarm was attracted by the aphid's honeydew excretions.  The aphids produced so much honeydew that it exceeded what the ants were "milking".  The aphids jettisoned this excess honeydew, as evidenced by the wet spot on the ground (next picture) below the colony.  The ants were there feasting at this honeydew puddle as well.
 Mosquitoes and other insects were there as well... feeding on the sparkling droplets of honeydew.
   Ants take their job seriously...protecting their honeydew source.  On several occasions I watched the drama of the ants battling the honeydew seekers.  In the center of the photo below, the ants have a mosquito stretched between several guards.  Below the captive mosquito, a hungry caddisfly has arrived for some honeydew.
Seconds later the small caddisfly was captured and hauled away.
Yep, there has been quite a show going on in our willow the last few months!
Winter's cold has quieted down all that flurry of activity.
Compare the next few pictures that show the aphid colony slowly dissipating in preparation for the dead of winter.
On (left picture) Dec. 1st, the colony was about at its peak.  On Dec 18 (right picture) there were noticeably less aphids
By mid-January there were only a few stragglers (perhaps dead ones) left hanging around on the willow
 All the winged adult willow aphids have gone somewhere to spend the winter... perhaps to more sheltered locations in the fencerow, or the woods across the river.  Wherever they went, I expect some of them to return to our willow next summer.  Possibly even the ones that stayed on the willow will be reanimated and begin another colony.
Then...the show will go on!

Saturday, January 21, 2012

Pennsylvania Logging History Told By An Old Stump - Another Tree Story

Old stumps in a bog can tell a story just as well as a tree.
  This ancient stump is a remnant from Pennsylvania's lumbering days of the mid 1800's to the very early 1900's.  The high stump tells a story of the lumberjack, his double-bit axe, and his crosscut saw - a fascinating part of Pennsylvania's history.

   Once upon a time this area was a Hemlock palustrine forest community, tall and thick with Hemlock, White Pine, and some scattered hardwoods.  Many of those trees probably sprouted back when Native Americans hunted this dark and quiet forest.
   Then one winter day a hundred years ago, along came the lumberjacks - the swampers and the loggers - they laid their axes to the tall timbers and let the daylight into the swamp.
   That day a lumberjack, most likely wearing a red mackinaw, lowered his double-bit axe and made a face cut in this medium diameter (but tall) pine at a comfortable height for his practiced swing.  Then he made the back cut with a crosscut saw that sent the tree crashing "down the mountain".  After the "stick" was limbed, and the saw logs bucked and sniped, the teamsters came with their horses and skidded the logs to a landing where (judging from the bog's location) a railcar-mounted, steam powered Barnhart loader lifted the logs onto rail cars for the log train to haul to the mill.  At the mill the logs were possibly sawn into boards for barn siding or perhaps some 2x's to help build a booming America.
  Charring on this stump, and others in the bog and surrounding forest, indicate a raging fire in the slashings.  This fire, or fires, along with erosion, changed the soil conditions and prevented recolonization of the area.  I wouldn't discount the role of  beavers, and of course, Sphagnum moss.  Then the bog formed, and like the stumps, lingered on for a hundred years or so, and told this story to a homeschool/nature guy/historian who decided to share it with people all over the world.

 Here are a few of the clues that "clued me in" on all this...
  • The tall stump.  Axe cutting is work best accomplished at a comfortable height... and above the buttresses, where there is less wood to chop.  Chainsaw loggers cut the stumps low... gaining a couple more feet of log.
  • The flat, back cut from the cross cut saw... there near my son's left elbow.
  • The face cut, or undercut (opposite my son)...a notch cut with an axe to direct the tree's fall.
  • The exposed roots... perhaps indicating erosion or loss of humus from fire.
When I see these old stumps... remnants of the lumbering days... I see this....
... thanks to an illustration on pg. 28 of book by Douglas Malloch
Tote-Road and Trail; Ballads of the Lumberjack, Illustrated in Full Color By Oliver Kemp

   I can "see" those woodsmen at work in these ghost forests, or stump fields, that are scattered around at various locations here in Pa.

  When I see those old, tall stumps, I can "hear"... the ring of the axes, the cries of the loggers, and the crack and crash of the trees as the timber was "layed low"... Then... the creak of the harness, the stomping feet of the horses, the clank of chains, and the chuffing of the steam locomotive as the logs were moved away and down the mountain. 
   In another swamp, pictured below, where I found evidence of a splash dam from the 1860's, I hear the rush of water and thudding of the jostling logs as the river drivers sluiced the logs and splashed them down the 'Scootac to the mill.
See what I mean? Stumps, even one hundred and fifty year-old stumps, can tell a story as well as a tree.

Wednesday, January 18, 2012

Sphagnum Moss' Cool Cannons

   "Sphagnum moss is cool!"  That's a quote from my daughter, who just now, looked over my shoulder and saw I had typed the words Sphagnum moss.  Now that's what I like to hear!   Especially since today is a typical, dreary, mid-winter day and we haven't talked about Sphagnum moss for months (I don't think I ever showed my kids the video of the Sphagnum's spore cannons firing).  I reckon my kids were impressed with this miraculous moss back in June and July when we were looking for orchids in the bogs.  Over the years, I have pointed out to them at least three amazing facts about sphagnum moss, so just now I showed the children this picture from 2010...
.... and gave them an impromptu quiz
"What are you looking at in this picture?"   They answered, "Sphagnum moss and its spore cannons."
"What is the bog made of ?"  They said, "Sphagnum moss, water, muck, grasses, and other things."   Oh, this is good!
What makes the bog?   "Well, the Sphagnum moss because it holds so much water and is so acidic."
Not bad!  Not bad at all...after a year and a half!
By the way, there's also a cool history lesson in that picture... can you see it?  Maybe I'll post on that next time.
   Sphagnum moss makes up much of the bog you see here.  The dead moss, or peat moss, has accumulated in thick deposits over time.  The live moss on the surface is mostly hidden by the various sedges and other plants, but Sphagnum is there in the background, just like the many, many Rose Pogonia Orchids in this photo.
The Rose Pogonias are much more visible from down at their level.  I was kneeling in the Sphagnum and getting very wet while taking this photo.
Rose Pogonia Orchids
Yes, the Sphagnum was there, but these beautiful flowers stole the show when I was posting some interesting facts about the Rose Pogonia Orchid.  The same goes for when I posted about the
Purple Pitcher Plant Flowers
carnivorous Purple Pitcher Plant  and about the pitcher plant's amazing flower.  There is a spectacular amount of sphagnum moss in these pictures... it's just "in the background" and easily overlooked.
However, Sphagnum moss has an incredible, explosive spore dispersal mechanism that deserves a shout out.
Sphagnum moss with explosive spore capsules
   The Sphagnum's spore capsule is designed to blow its top and rapidly expel its spores.  In doing so, a turbulent vortex is generated which helps loft the spores higher than a simple "poof".  This feat is accomplished as the round spore capsule dries out and collapses into a cylindrical shape which compresses the air to the point that the cap pops off.  The sudden rush of air and spores through the resulting round hole generates a "smoke ring" which carries the spores sufficiently high enough to catch a ride on more turbulent air than the light spores would be able to reach without the aide of a vortex.
Popping peat moss!
Here's a link to a video about the discovery of the fact that an exploding Sphagnum spore case generates a turbulent vortex.  The video includes footage of the spore cannons "firing".
   In the photo below, the cylindrical-shaped spore capsules have already fired their spores, or are about ready to do so.
When I look over the expanse of a bog and think about all the Sphagnum moss and those many minute cannons, I can almost hear a Sphagnum cannonade.
Boys on a bog slog
    I chose to post about the spore cannons and some of the Sphagnum's bog companions to add some "pop" and color to my mid January posts.  In the picture below, the Sphagnum moss may be inconspicuous, but knowing it's there adds some "pop" to the colorful picture of the Grass-pink Orchids.
Grass-pink Orchids
   I could quiz my children about this bog picture as well, but I guess I won't, because I'm sure they haven't forgotten those amazing bee-bopping orchids, the Grass-pink Orchids.  Also, since it's a bog photo, there is the ever-present Sphagnum moss.... of course they'll remember that.  Another reason to wait to quiz the children is because I can see a number of bog-related things in the frame of this picture that I haven't pointed out to them... yet... I guess we'll have to go on another bog slog.  Now, that is a pleasant mid-winter night's dream! 

Saturday, January 14, 2012

Cliff-dwelling White Pine - Another Tree Story

An unusual White Pine - the subject of this post - barely made it into the upper left of this picture.
   At the time, I was trying to capture the impressive cross-bedded sandstone outcrop, not the precariously perched pine tree.  Those are some really nice rocks!
   The tree, however, is equally impressive, as it hangs out on the edge of the sandstone ledge.
   A little later, when I noticed the amazing tree and realized it would make a great "Tree Story" post, I took some photos of the pine clinging to the edge of the crevasse.
The pine is doing rather well, considering the tough living conditions it faces in its own little corner of the world.
 Now, for the tree story....
    Long ago, and far out on the mountain... on a bastion of rock at the edge of a precipice, a White Pine seed sprouted out of a crack in the sandstone ledge.  What fateful event dropped it there?  A gust of wind up through the fissure?  Dropped by a careless squirrel?
   Whatever the cause of the seed's deposition, the spot it landed had the right conditions for germination and for the seedling to take a hold and grow.
   As the young pine grew, its roots propagated along the crack, and as time progressed they wedged the crack farther apart by hoisting up the many hundreds of pounds of rock above its roots. 
White Pine is a soft wood, but that said, here it is displaying incredible strength.
  Water is a little scarce sometimes on this island of rock.  Soil is even scarcer.  Life would be a whole lot better for the tree, had its seed landed at the bottom of the precipice.
 But hey, what other choice did the tree have.... but to do the best it could in its limited circumstances?
 Long ago, when the seed landed right there on the corner of that ledge.... what else could it do, but...
.... "bloom" where it was planted? 
Well done, pine tree!
  Then along came a naturalist and his boys, and appreciated the tenacious tree, and tried to capture (on camera) the lesson from the tree's story to share with the world.

Tuesday, January 10, 2012

Witches' Brooms Overhead

Witches' brooms are the cause of these strange, dark silhouettes high in the tree tops.
These dark, "fingery" clusters floating in the tree branches sure catch your eye... especially in the winter time.
 I didn't take note what kind of tree was hosting these witches' brooms, but I'm pretty sure it's a Juneberry tree (Amelanchier sp).
Witches' brooms are dense, abnormal growths of branches.

 These strange looking deformities can be caused by mites, fungi, or even mechanical injury.
Here is a picture of a smaller witches' broom.

 Apparently, it is fairly common for the brooms on Juneberry to be caused by the fungus, Apiosporina collinsii.

 Not very far away from the witches' broom decorated Juneberry trees, was this witches' broom in a Pitch Pine.
   This abnormal growth on the Pitch Pine manifests itself as a very dense, dark, bushy area part way up the tree.  In its present state the witches broom is somewhat interesting-looking, although it isn't very pretty.  Genetic mutants like these sometimes do actually have a pleasant use.  Can you imagine one?

   I planted a witches broom at our "old" (previous) house...see the Bird's Nest Spruce to the right of the front porch and left of the ornamental grass?
   Bird's Nest Spruce is a popular foundation planting which is propagated from witches' brooms on Norway Spruce. Cuttings from these brooms are grafted on other rootstock.  Various dwarf varieties of landscape cultivars, as well as some bonsai trees, originate from witches brooms.
   Can you see it now.... the wild, mutant miniature... high in the tree, waiting to be cut, brought down to earth, and grafted and trained into something beautiful?
Mite bitten mutants, anyone?
Or maybe I should say, "Could you make use of a mold molded mutant miniature"?
At any rate, there are some beautiful bonsai bouncing in the breeze...  high in the boughs of the forest trees.