Thursday, September 27, 2018

Climax of the Year

     Sometime around September 21st is the autumn equinox and, to me, the middle of fall and the climax of the year.  The spring and fall equinoxes are the only times of the year when each part of the entire Earth receives 12 hours of sunlight and 12 hours of darkness, from pole to pole, as a result of our planets' tilting 23 degrees on its axis as it circles the sun.
     According to the human calendar, autumn is from about September 21 to around December 21, a total of three months.  Each season is three months long.  But I think fall in the Mid-Atlantic States runs from about August 7 to around November 7, a total of three months, with September 21 in the middle of that season.  I see autumn in August because of the lesser amount of daylight each succeeding day, the migration of shorebirds, swallows and other bird species and the climax of much plant growth.
     By September 21 in the Middle Atlantic States, most vegetation attained its peak of growth and produced its seeds nuts or berries.  It reached its climax.  Weedy fields won't get any weedier. Thickets of trees, shrubs, vines and tall weeds and grasses won't get any thicker and some gardens, roadsides and abandoned fields won't get any more overgrown with plants than late September.
     Most seeds, nuts and berries will be eaten by rodents, birds and other kinds of wildlife through fall and winter.  But those that survive being ingested, and find suitable conditions, will sprout during the warmth of the next spring.
     Wild plants and animals prepare for the coming winter in autumn.  Many kinds of birds migrate south to find reliable food sources.  Their job done, deciduous leaves and their green chlorophyll die, revealing the reds and yellows that were in those leaves all summer, but dominated by chlorophyll.  By late September one can see colored leaves on black gum, staghorn sumac, sassafras, red maple, sugar maple and a few other types of trees.  The tops of many ground plants die, but their perennial roots live and sprout new tops the next spring.  The cold-blooded reptiles and amphibians, and many kinds of invertebrates, retreat to sheltering places for the winter.  Wood chucks and black bears put on layers of fat to survive that harshest of seasons.  Squirrels, chipmunks, beavers and blue jays store food for winter consumption.  And those alleged forecasters of winter's severity, the handsome, bristly woolly bear caterpillars, the larvae of Isabella moths, bustle across country roads in search of shelter in the ground for the winter.
     While I rejoice in the overwhelming bounty and beauty of wild vegetation and wildlife in fall here in the Mid-Atlantic States, I also feel a bit sad around the autumn equinox, and in fall, because they represent the coming of cold, snow, ice, increased darkness each day, and the resulting dormancy of many wild plants and animals.  Maybe it's because most wildlife is not courting and much vegetation is dying, reminding me that all life, including mine, comes to an end.  Cheering bird song no longer fills the woods and thickets.  Vegetation is no longer growing.
     But there is much beauty and serenity in our woods, fields and roadsides during late September and into October, including the beauties of flowers that bloom during late summer and into fall.  Some of the more common, pretty flowers we see along roadsides and field edges are goldenrods and Jerusalem artichokes with their boldly-yellow blossoms on tall stems.  Some damp meadows and roadsides are dominated by a couple of species of asters, one kind with small, white flowers and the other with little, pale-lavender ones.  Other flowering plants in certain moist pastures and roadsides include the abundant and bushy-looking spotted jewelweeds with orange blooms, bur-marigolds that have yellow blossoms, smartweeds with their pink flowers and great lobelia that have blue flowers.
     The innumerable aster and jewelweed flowers supply much nectar to wildlife in autumn, the last copious amounts of that sugary liquid those creatures will get for the year.  Many bees, butterflies and other kinds of insects visit aster blossoms, while migrating ruby-throated hummingbirds dip their long bills into jewelweed blooms.        
     The countryside in the Mid-Atlantic States is beautiful around the autumn equinox and into October.  And there is a profound and notable climax of plant growth and wildlife activities at that same lovely time of year.  Then nature prepares for the coming winter, which is a period of dormancy used to gather resources for the next push of growth in spring.        
    

Monday, September 24, 2018

Migrants Seen From Our Deck

     I have watched the September migrations of birds and insects from many places in Lancaster County, Pennsylvania, including on ridge tops and in farmland.  And on September 20, a few days ago, I saw migrations of birds and insects from our deck in a suburban area of New Holland, Pennsylvania.  I started at 12 noon that day when I spotted an osprey and a broad-winged hawk soaring southwest over our house.
     The sky was partly clear that day, with temperatures in the high seventies and the wind blowing from the south.  Hawks and eagles generally follow the southwest running Appalachian Mountains on strong north and northwest winds.  Those winds push up the northern slopes, forcing the raptors up as they sail along the ridges for miles with scarcely a wing-beat, which conserves their energy.  But on south and southwest winds, the raptors scatter in a southwesterly direction over farmland, suburbs and cities, as those birds continue on to their wintering territories.
     Hawks and eagles that migrate over farmland and cities rely on thermals to give them lift for easy soaring for miles and miles.  Thermals are rising columns of warm air, heated by sunlight shining on the soil of fields and the concrete and asphalt of cities.  As the warmed air rises, it pushes the raptors up with it.  
     While watching the sky from our deck, I saw about eight chimney swifts careening swiftly across the sky after flying insects to eat.  Probably birds that hatched here in New Holland, these swifts will soon join others of their kind in flocks to drift south to northern South America to consume insects while waiting out the northern winter.
     I saw an occasional monarch butterfly flutter over our neighborhood.  Presumably, some were going to Florida to spend the winter, while others were traveling to certain wooded mountains in Mexico.  But each one was migrating to the place where its wintering great-grandparents came from in March of this year.  Miracle of miracles, they find their way without being in those wintering places before.  
     At different times, I saw two groups of broad-winged hawks, named for their wide wings, swirling fairly low over our neighborhood, one flock had eight hawks in it, while the other had seven broadies and two bald eagles, one of the eagles being an immature bird.  As I watched, each gathering of raptors suddenly stopped whirling and peeled off in a line toward the southwest.  What a thrill to see two bald eagles over our house at one time!
     About 3:00 pm, I saw a flock of about 24 broad-winged hawks swirling together before a white cloud high over our property.  I would not have seen those hawks without that cloud formation in their background.  And, as always, the broadies soared out of their circle and sailed swiftly away in a line to the southwest.             
     I have always enjoyed puffy, white or gray cumulus clouds, the kind we can imagine looking like most any objects on Earth, including human faces.  But now these floating pillows in the sky help me see, and identify high-flying birds by their silhouettes and styles of flying or soaring.
     Late in the afternoon I saw two flocks of blue jays migrating low through our neighborhood.  Each bird flapped in the way of its species, which helped identify it.  One group had about 20 individuals, while the other had seven.  These jays could have been from farther north in the United States or southern Canada, places where they raised young.  Both those northern areas can have harsh winters.
     While watching the sky for migrants, I also saw some what I thought were local birds; non-migrants.  A red-tailed hawk flew low over our neighborhood, probably searching for gray squirrels.  I saw a Cooper's hawk dashing over our lawn in its quest for mourning doves and house sparrows to catch and eat.  And I saw a few turkey vultures soaring majestically over our home.  
     I checked the September 20 statistics of Hawk Mountain Sanctuary on the Blue Ridge Mountains of Pennsylvania.  Observers there saw few migrating raptors that day because of the south winds, but tallied many monarchs and blue jays, as I did at home. 
     Migrant raptors in autumn can be spotted almost anywhere in southeastern Pennsylvania, as elsewhere, when winds blow from the south or southwest.  One can even see migrating hawks and eagles at home on those winds, if one watches for those birds high in the sky.   

Migrants Seen From Our Deck

Wednesday, September 19, 2018

Hints of Autumn

     On the afternoon of September 14 of this year, I took a drive through Lancaster County, Pennsylvania farmland to see what was happening in nature.  The sky was overcast with temperatures in the high 70's and a humid breeze, which is often typical weather here in early autumn.  There was a "feel of fall in the air".
     After a ten minute drive from home, I came to a meadow, a stream and a bottomland woodlot, all in one place that I occasionally visit.  There I saw the floodplain trees that grow along the waterway and in the pasture, several kinds of roadside, fall flowers, yellow sulphur butterflies and bees among the blossoms, and a few colored leaves.
     Floodplain trees in the woods include sycamores, shagbark hickories and river birches with their picturesque bark, white, swamp white and pin oaks with their acorns that feed white-tailed deer, gray squirrels and deer mice, black walnuts with their nuts that only squirrels can chew into, and silver, red and ash-leafed maples.  These trees adapted to tolerating the constantly moist soil of a bottomland, creating their own communities of trees in a riparian forest.  Sycamores have mottled bark, river birches have bark that peels into thin, curly strips that remain attached to trunks and limbs, and the hickories have long, vertical strips of solid bark, each one loosening at both ends from trunks and branches, giving the hickories a shaggy appearance.
     The autumn flowers I saw along the sunny edge of the woods and in the meadow were the orange ones of spotted jewelweeds, the yellow blossoms of pale jewelweeds, the golden flowers of goldenrod and tickseed sunflowers, the hot-pink blooms of ironweed, the pink of smartweed, the white of knotweed and the blue blossoms of great lobelias.  All these plants, but the lobelias are tall, and all of them, but goldenrods grow best in damp soil.
     Bumble bees visited the sunflower blooms to sip nectar.  Tiny skipper butterflies were on lobelia flowers while several yellow sulphur butterflies visited ironweed blossoms.  These insects added more interest to the flowers.
     Many of the black walnut trees and poison ivy vines had some yellow leaves on them, hinting again at autumn.  The poison ivy vines also had clusters of off-white berries that mice, squirrels and berry-eating birds consume in fall and winter, with no harmful affects.
     There also were some colorful berries on other kinds of plants on the edge of the woods.  Pokeweeds had deep-purple ones on pink stems, which causes a pretty color combination.  And multiflora rose bushes had numerous red berries among the green ones that didn't ripen yet.
     There were other kinds of invertebrates along the woods edge and in the meadow that indicated autumn.  I heard a mole cricket chirping from his underground burrow in the meadow, a call to females of his kind to join him in mating in his tunnel.  A big, beautiful female black and yellow garden spider perched in her large orb web hung from the wires of a fence.  She had grown all summer and was now ready to reproduce.  And there were several dragonflies of some kind hawking low over the tall grass of the pasture in search of flying insects to catch and ingest.  Those dragonflies might have been migrants, stopping long enough for a meal.
     I saw only a few birds in that spot in farmland, one per habitat.  A great blue heron flew up from the stream where it had been fishing.  A Carolina chickadee flitted among twigs in the woods, probably picking up tiny invertebrates to eat.  And an American kestrel, perhaps a migrant, perched on top of a dead tree in the pasture as that little hawk watched for mice and grasshoppers to ingest.
     After about an hour, I left that spot.  But I was filled with the beauty and intrigue of early fall.            
        



Thursday, September 13, 2018

Sphinx Moths

     Sphinx moths are so-named for their smooth-skinned caterpillars' reared up heads when threatened that makes them look fierce, and making them resemble the Egyptian sphinx.  The beautiful adult sphinx moths are also called "hawk moths" for their stiff, swept-back wings that beat rapidly, causing swift flight.  Each species in this moth grouping has a stout, hairy thorax and abdomen and attractive color patterns, most of which blend the moths into their surroundings to avoid predators.
     Adult sphinx moths of each species have long proboscises they dip into flowers while hovering to sip sugary nectar from them.  And each proboscis is coiled away under the head when not in use.  The three kinds of hawk moths I see most commonly here in Lancaster County, Pennsylvania are clear-wing hummingbird moths, white-lined sphinx moths and tomato hornworms, in that order of sighting them.
     The lovely and fascinating clear-wings resemble hummingbirds in the way they hover before flowers in daylight and bumble bees because of their size, shape and coloring.  Each one has a two-inch wing-span and clear, see-through spots in their wings.  The tips of their abdomens look "feathery" and, to me, are shaped like the end of the tails on crayfish.  And they have large eyes with what appears to be a pupil in each one.
     Clear-wings live among gardens, thickets, hedgerows and woodland edges, places where flowers are likely to be, through much of the eastern United States.  And its in those habitats that the larvae consume honeysuckle, dogbane and the foliage of other kinds of plants.  Clear-wing caterpillars are mostly green, which camouflages them among the plants they eat, and there is a small, red dot on each side of every segment.  And like the larvae of all sphinx moths, each clear-wing caterpillar has a fleshy "horn" on the upper part of its last segment.  That growth resembles a stinger to discourage would-be predators, but it is a bluff because it is harmless.
     The handsome adult white-lined sphinx moths have three inch wing spans and are mostly light-brown with white lines on their bodies, heads and wings, a color pattern that camouflages them by day when they are resting.  They also have striking pink and black on each back wing and large eyes, in which one can see their pupils. 
     This species lives in pastures, gardens and woodland edges across much of the United States.  And like most hawk moths, white-lines visit blossoms at night.
     White-line caterpillars are green and dark-striped, lengthwise from head to rear, which blends them into the plants they consume.  They ingest the foliage of evening primrose, grape, tomatoes, apple and elm trees, and the leaves of other kinds of vegetation.
     Tomato hornworm moths live in the eastern half of the United States.  This attractive, nocturnal hawk moth has a four inch wing-span, a mottled gray and brown coloring all over, except for ten obvious and lovely orange spots on their abdomens, five on each side.
     I've seen tomato hornworm larvae far more often than the adults in my lifetime.  I see those caterpillars mostly in tobacco fields where they ingest tobacco leaves.  Each larva grows up to four inches long, is mostly green, which camouflages them among the foliage they eat, and has a white line diagonally across each segment and a fake "eye" on each side of every body section.  These caterpillars can be destructive to crops, including tomatoes and tomato leaves.
      Sphinx moth larvae pupate in brownish, crispy cases in the ground.  The developing proboscis of each caterpillar is so long it grows outside the main case, making it look like a tiny jug with a handle in the soil.   
     Sphinx moths are unique and attractive.  They are well worth spotting in their sunny, flower-filled habitats.              

Monday, September 10, 2018

Autumn Insect Flowers

     Gatherings, even swarms, of bees and butterflies congregate on a variety of beautiful pink and purple flowers during September, into October, to sip sugary nectar.  Some of the last blooms of the year in southeastern Pennsylvania that produce copious flows of nectar that attracts multitudes of insects, they include the pink blossoms of red clover, ironweed and purple loosestrife, and the lavender flowers of alfalfa and New York asters.  All these blossoms are appealing in themselves, and intriguing in the many insects that are attracted to them during warm, sunny afternoons in fall.  Together, they make autumn fields, meadows, lawns and roadsides, all of which are human-made habitats, more enjoyable to experience.  
     Red clover is a kind of hay crop originally from Europe.  The lovely flowers of this species cover acres of farmland between cuttings during summer and autumn, and many stretches of rural roadsides that are not mowed.  Periodic cutting of the plants in the fields causes them to produce more, and more, blooms, spangling those fields with pink and the fluttering of colorful butterflies of several kinds.  Plus white-tailed deer, wood chucks and cottontail rabbits from nearby thickets and woods ingest red clover plants, the chucks during the day and the other species at dusk and dawn mostly.
     Native ironweed grows up to five feet tall in the damper parts of sunny pastures, and they have hot-pink blooms on top of their stems from August into October.  Those attractive flowers are often nearly covered with a variety of butterflies, including a few swallowtail species, cabbage whites, yellow sulphurs, monarchs, silver-spotted skippers and others, helping make those meadows be more alive.
     Purple loosestrife is an alien, invasive species originally from Europe.  Though abundant in many parts of the eastern United States, I don't see much of it here in southeastern Pennsylvania.  This plant can grow to five feet high in moist, sunny habitats, including cattail marshes, and has pretty, pink flowers all along its stems.  And those plants swarm with bees and butterflies during late summer into fall.
     Originally from Europe, alfalfa is an abundant hay crop that covers thousands of acres in southeastern Pennsylvania.  This plant has pale-lavender blooms that have a sweet scent.  And, of course, gatherings of buzzing bees and fluttering butterflies move among those lovely, innumerable blossoms to sip nectar all summer and deep into autumn.       
     New York asters are a native species that has deep-purple flower petals and yellow stamens in each bloom, making a striking contrast of colors from late August into October.  This beautiful plant grows in abandoned fields, often with the golden blooms of goldenrod, making a lovely combination of colors, here and there along country roads, and in some lawns of people who appreciate them.  And like all the blossoms in this grouping, these asters are attractive to many bees and butterflies and other types of insects seeking nectar.
     These flowers bloom late in summer and into fall.  They are beautiful in themselves and intriguing with swarms of insects of several kinds that get the last flows of nectar of the year from them.  Readers should try to get out and enjoy those lovely blossoms, and the multitudes of interesting insects that visit them.                 

Monday, September 3, 2018

June Beetles and Digger Wasps

     I see small gatherings of green June beetles flying low over our lawn and other lawns during July in southeastern Pennsylvania and digger wasps, often in little groups, sipping nectar from flowers during August and September.  These two kinds of insects have a relationship that most people don't see or know about.  They are part of a food chain.
     Inhabiting sunny, open habitats through much of the eastern United States, adult June beetles emerge from the ground in July in southeastern Pennsylvania.  Almost an inch long, bulky and green on top, these noticeable beetles appear bumbling as they zoom low over the ground, some of them bumping into things such as screen doors and windows.  These attractive beetles sip fruit juices and nectar from flowers, and search for mates.  Females also look for places to lay eggs in the ground. 
     Hatched larvae dig down in the soil, ingest the roots of grass and other plants and winter in the ground.  There they pupate late the next spring and emerge as adults in July ready to reproduce.  
     But many June beetle larvae never mature because they are meals for digger wasp larvae in the ground.  Adult digger wasps are dark, over a half-inch long, with orange abdomens, which make them attractive.        
     Digger wasps are mostly seen sipping nectar on a variety of blossoms on lawns and roadsides, and in hay fields across much of the United States.  Each adult female digger wasp digs into the soil, including on lawns, to find June beetle larvae.  When she finds each of several June beetle young, each female digger wasp paralyzes the prey, digs a chamber around its body and lays an egg on it.  The wasp youngster consumes the beetle larva, overwinters as a pupa in the ground and emerges the next summer ready to mate and lay eggs on June beetle larvae.
     These two types of attractive insects have interesting life histories on our lawns, making those human-made habitats more intriguing.  And these insects are part of a food chain, from sun and rain to plant roots, beetle larvae and digger wasps.  Adults of both these insect species also pollinate a variety of flowers, which I like to see as well.  These are more kinds of life adapted to built environments where we can enjoy their beauties and intrigues.