News blog

For the Birds

winter-red-bellied-woodpecker-jennifer-wosmanskyDo you put seed out for birds in winter?  Millions of Americans enjoy this hobby, even those who might not otherwise be nature-lovers.  We string up suet for woodpeckers and scatter sunflower seed, millet, or corn to attract our personal favorites, perhaps the cardinal, or goldfinches.  Some birds are finicky about visiting feeders, and we delight in adding another species to our list – mine is currently at eleven for 2017, but should reach fifteen or so before winter is over.  I like to watch the Red-bellied woodpeckers, which are much more numerous this year than last.  They are expanding their range further north as our winters grow more mild.

coopers-hawk-adultWhen I visit my mother in Vermont in a few days, I look forward to seeing her regular birds, so different from mine:  crossbills and snow buntings, and red-breasted nuthatch.  I might see a Cooper’s hawk in either location as they too have expanded their range, to prey on the birds that we attract to our feeders!

Some of you may wonder, is it necessary to feed birds, and can it be harmful?  There are no conclusive data showing its benefit or harm to bird populations, although centralized feeding areas can be reservoirs for the spread of disease.  It is a good idea to scrub down your feeder periodically, and to offer fresh water if you are providing any.  The availability of water is a limiting factor for bird distribution, especially during freezes in winter, when I find dense concentrations of birds near flowing streams.  Will the birds starve if you stop feeding them or miss a few days?  Unlikely.  Their numbers are determined by many factors in addition to food, and birds are adapted to move and forage over a wide area.

It is more important to support birds with a healthy habitat of native trees and plants than it is to provide supplementary foods in any season.  Trees moderate our climate, provide shade and shelter and seed, and most critically, harbor vast numbers of insects.   Some birds are almost entirely insectivorous, like the Eastern 028bluebird, while others depend upon insects for short periods of growth and transition.  According to entomologist Doug Tallamy, ninety-six percent of terrestrial birds rear their young on insects, especially caterpillars.  Many non-native plants do not support the kind or number of caterpillars that birds need, and when those plants become numerous enough to compete with native plants for space and light, the number of birds on the landscape will be diminished.  Even non-native plants that appear to feed birds, like Asiatic bittersweet, can be low-quality food sources that provide less nutrition than native plants.  We have seen a tremendous increase in the number and diversity of birds at the Armstrong Preserve and Education Center after we replaced our invasive non-native plants with native species.

Here is a list of things you can do to attract songbirds to your property, including suggested native plants for food sources, taken in part from bird habitat specialist Dr. Stephen Kress:

  1. Maintain a border of native trees and shrubs around lawns, and minimize the area of lawn.
  2. Create a brush pile.
  3. Remove invasive plants.
  4. Rake leaves under shrubs to create feeding areas.
  5. Clean out bird nesting boxes in early spring.
  6. Create a water source for bathing and drinking.
  7. Clean feeders with a 10% non-chlorine bleach solution.
  8. Keep cats indoors.

Spring and Summer Seed Producers = Red maple, American elm

Early Summer Fruit Producers = Black raspberry, High and Lowbush blueberry, Pokeweed, Shadbush

Autumn Seed Producers = Sugar maple, Eastern hophornbeam, the ashes

Autumn Fruit Producers = viburnums, dogwoods, Common elderberry, Spicebush

Winter Fruit Producers = Bayberry, Eastern red-cedar, Highbush cranberry, American holly, Inkberry,  chokeberry, Wild grape, Virginia creeper, Winterberry, Staghorn sumac

Herbaceous plants = asters, Black-eyed susan, thistles, phloxes, sunflowers, goldenrods

Nectar Plants for Hummingbirds = Jewelweed, Cardinal flower, Trumpet honeysuckle, Indian paintbrush, Tulip tree

 

Spring Calendar of Guided Hikes at PRLC Preserves

Russell hikersWelcome and Happy New Year!  We are looking forward to this year’s suite of guided hikes with PRLC’s Land Steward & Educator, Krista Munger.  First we will go to the Clark Preserve for a winter wildlife identification walk on January 28 (See Link).  Conditions may be right for snowshoeing, but don’t be concerned if you don’t have them – several of us will walk ahead and pack down the trail for you.  On March 26, we will search for early signs of spring at Halle Ravine Preserve and hope to see frogs, toads, and salamanders emerging under the green ferns and mosses.  Practice identification of trees by their bark, buds, and branching on both excursions.  Our focus on May 21 is wildflower identification in the Armstrong Preserve’s outdoor classrooms, including the Working Backyard where we grow native trees, shrubs, and plants for use in restoration projects in our preserves.  Bird migration will be in full swing and the vernal pool should be full of frogs, so bring binoculars and plan to spend the afternoon exploring whatever interests you most in nature.  There may even be morel mushrooms!

To receive a reminder ahead of each of these events, please join our mailing list.  We will send you an email about once per month.  We also have a series of volunteer work dates scheduled for the Spring beginning on March 4 at Clark Preserve.  Please see our events calendar for other dates, and email Krista at landsteward.educator@prlc.net for more information and to sign up for email reminders on volunteering opportunities.  You can like us on Facebook too!

Evidence of Geologic History at Bye Preserve

bye-geologyThe stony ground and prominent rock formations of Pound Ridge in Westchester County, New York elicit curiosity in many people, some of whom attended our recent guided hike focused on geology. I will summarize our tour of the geologic history that can be seen at the Bye Preserve, owned by the Pound Ridge Land Conservancy (link to map and directions).  Trails at the Preserve are open everyday from dawn until dusk.

Imagine that your arm represents geologic time, with your armpit being the Big Bang and the tip of your middle finger representing today.  The dawn of life occurs just above your wrist.  Between your wrist and the middle of your palm, all of the bedrock that shapes this land was formed by a process known as the tectonic cycle:  erosion of mountains, deposition of materials in layers, subduction (movement of the earth’s crust), and volcanism.  There was something on the earth’s crust prior to the formation of our bedrock, of course, but we cannot see evidence of that now.  Geologists have discerned that an ancient Acadian Mountain Range once rose east of us, to the height of the Himalayas, and then eroded into particles that were later metamorphosed into our bedrock.  Add folding from the movement of tectonic plates, deformation by glaciers, and erosion, and you have a punctuated record of history etched on the landscape.

Fordham gneiss bedrock exposed on the surface

metamorphic-sedimentary-layers

Metamorphosed sedimentary layers, eroded and tilted

 

 

 

 

 

 

In its western half, the Bye Preserve is underlain by Fordham gneiss, which formed in the Precambrian era, 1.1 billion years ago.  This layer measures up to 500 feet thick and is extremely resistant to weathering.  There are many kinds of gneiss, and it is variable in color from brown to buff and can be pink or green.  Fordham gneiss contains quartz, biotite mica, silicates, garnet, and other minerals.  Bedrock along the eastern side of Bye belongs to the Hartland Formation, which is half as old and is a mixture of gneisses, schists, and amphibolites.  It formed when shales and sandstones from a deep ocean metamorphosed and retains its layers of alternating color.  Many of these rocks were inverted when the Hartland Boundary Fault displaced older layers and brought in new rocks.

muscovite-mica

Muscovite mica

Granite

 

 

Subsequent to the last great tectonic shifts in the Paleozoic era, the bedrock at Bye has endured at least four episodes of folding and associated metamorphism, which is visible in many rocks where layers are curved rather than straight.  The first stage of folding produced large ENE-WSW trending ridges and valleys, while the second stage trended NNE.  Later stages produced tight folds that reoriented earlier folds.  Where rock is resistant to bending, brittle faulting may occur, which produced the Mill River Gorge just northeast of Bye Preserve and the Mianus River Gorge as well.  In the midst of these changes, magma intruded the bedrock at Bye and produced a very pretty white-to-pink granite that is rich in quartz and mica.

Metamorphosed layers, block faulting

Metamorphosed layers, block faulting

Folding

Rock tumble from brittle fault

Rock tumble from brittle fault

 

 

 

 

 

 

 

 

 

 

More recently in geologic time, between your furthest knuckle and fingertip on our imaginary time scale, the glaciers of the Ice Age left their mark.  An ice sheet more than one mile thick ground back and forth across this landscape for nearly 100,000 years in freeze/thaw cycles.  Each advance brought in new rock from afar.  Each period of retreat caused mass deposition, flooding, and a rise in sea levels.  Bye Preserve is now only ten miles from the Long Island Sound and was at times submerged by ocean, although fresh water has played a greater role in carving this landscape. We can see evidence that great torrents once ran in the boulder fields that line two now-intermittent streams, scouring away soil such that even today, only ferns and moss grow there.

The last glacial ice disappeared from Pound Ridge about 12,0000 years ago, leaving behind piles of sand, rock, and even huge boulders on the surface of our scoured bedrock.  These are the clues from which we can piece together millions of years of history on the land.  To end our story, I invite you to sit with a favorite rock and to ponder what it has endured to bring you both to this moment in time.

variation-in-gneiss-rocks-moved-by-glacier

Variation in gneiss moved by glacier

glacial-erratic-boulder-with-lichen

Glacial erratic boulder with lichen

Boulder showing evidence of glacial tumbling and erosion

Intermittent stream bed showing many phases of geologic activity

ferns-and-moss-in-a-rock-strewn-valley

Ferns and moss in rock-strewn valley

upturned-metamorphic-sedimentary-rock-with-glacial-scarring

Upturned metamorphic sedimentary rock with glacial scarring

 

faulting-caused-by-the-expansion-of-freezing-water

Cracking caused the expansion of freezing water

 

 

 

Volunteers Remove Old Bridges from Halle Ravine

Sixteen people attended our end-of-year Saturday morning work session at Halle Ravine and helped to remove old bridges from deep in the Preserve.  Students and seniors, mothers, and dads all carried out boards and even one entire bridge, as shown in this video.  Together we are stronger!  We leave the forest, stream, and trails in better shape after much work in Halle Ravine in 2016.   Projects are ongoing to control invasive species around the pond, with planting planned for this Spring.  We also plan to replace the decking on one or more bridges next year.  Be in touch to lend a hand!

img_20161203_104139324img_20161203_104136114halle-bridgesimg_20161203_094431505

 

 

 

Assessing the Impact of Deer Browse on Forest Regeneration

Browse Line by Andy Jones

Browse Line by Andy Jones

Forests in Pound Ridge and surrounding areas are under siege by one of the gentlest of animals, the white-tailed deer.  Deer are keystone herbivores and eat from five to seven pounds of vegetation per day.  In summer, deer dine richly on the buffet of tender plants provided by home landscaping.  In winter, our subsidized deer herds turn to the forest to browse buds, tender saplings, and even tree bark.   At ideal densities of 10-15 per square mile, deer browse checks the growth of plant life without hindering forest regeneration.  At higher densities, they can strip the understory bare.  With deer density in Pound Ridge as high as 65 per square mile, we face the loss of wildflower species first, and then the pollinators that depended upon them, and then the birds that can’t find shelter or food, and finally, the forests themselves as trees are not replaced.

deer_exclosure-areas-definedIs the situation really so dire?  Scientists and natural historians have documented all of these effects, including our friends at Mianus River Gorge who found that tree sapling diversity in a local protected forest decreased from 15 species to 4 over the last thirty years, due to overbrowse by deer.  Local land managers seek solutions, but first we must know our problem.  I will describe here a simple method for assessing the level of deer browse in virtually any patch of forest in Pound Ridge.  Rather than counting deer or deer density, we are going to measure the effect of deer browse on each plot and use that as a baseline that guides future management.  This methodology was developed by Thomas Rawinski of the United States Forest Service, who shared his knowledge and skill with us in a training session this summer.

We begin by choosing a site for our study plot(s).  The circular plot covers 100 square meters and must include at least ten measurable saplings of one of the indicator species.  Measurable means that the sapling is still below the average browse line and therefore vulnerable.  Indicator species include any browsed species with beech and sassafras preferred followed by the shrubs; maple-leaf viburnum, sweet pepperbush, alternate-leaf dogwood, red elderberry, choke-cherry, and even the invasive burning bush.  I do not mean to imply that deer prefer these plants – rather, they avoid them – so that browse levels reliably indicate the severity of deer pressure on forest growth.

Barren understory in midsummer

Barren understory in midsummer at Armstrong

Once the indicator plant has been selected and the plot margins delineated, we set out to find the ten tallest measurable saplings of our chosen species.  Then we average those ten measurements to find the definitive “tallest” for that plot.  In itself, this doesn’t tell us much.  Over time though, we can discern trends and hope to associate those with management actions.  We can also make comparisons among plots to measure relative levels of browse across landscapes.  For example, Sugar maples at Armstrong were browsed down to 8.9 inches, while those at Halle measured 8.1 inches.  Deer pressure may be more severe at Halle than it is at Armstrong.

We can avoid the costly and time-consuming task of measuring deer density by using this simple approach to assess deer impact on our preserves.  We will measure again next year and compare our findings both within PRLC holdings and with a larger community of land managers and report back to you then.

deer-impactsFor more information, please see http://www.na.fs.fed.us/pubs/2014/NA-IN-02-14_WhitetailedDeerNEForestsWEB.pdf 

 

Amateur Geologists Converge on Bye Preserve

boulder-field-from-glacial-recessionTwenty-three people attended our guided geology tour of Bye Preserve on Nov. 12 and saw firsthand how history has shaped this land for the last 1.1 billion years.  Stay tuned for a summary and photos of what you can find on your next visit.

Halle Ravine Volunteer Projects

img_20161001_111157107 A dozen community members assisted in native plant restoration at Halle Ravine at our most recent Volunteer Work Session on October 1.  A lively group of students, neighbors, town officials, and PRLC board members spent the morning working on and off trails in the north end of the Preserve and along the steep bank of the eastern side of the ravine.  They cleared invasive weeds, planted a variety of native plants that will better support wildlife, and fenced valuable trees and shrubs from deer browse.  Our aim is to encourage more shade cover in the Preserve to protect soils from erosion and drought and to provide for the needs of animals.  Come out for a tour with us next summer and see the results!

We also completed the installation of a new staircase along the steepest section of trail in the Preserve.  Help is still needed to carry out construction materials and begin bridge repairs, so please join us on Saturday November 5, 10am-noon to lend a hand.

 

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carson-p-at-halle-ravineimg_20161001_131321605

 

 

 

These projects were supported by funding from the Land Trust Alliance Conservation Partnership Program and by private donors.

 

Fall Mushrooms at Armstrong Preserve, Pound Ridge NY

We had a great turnout for the mushroom hike at Armstrong Preserve on October 23, 2016 and turned up some interesting finds.  The most distinctive was a single specimen of the Dog stinkhorn, Mutinus ravenii, so-named for its shape and strong odor.  We also found a few edibles, noted in the captions below.  Please use caution when foraging for wild mushrooms and refrain from eating any that are not verified by an expert.  Please also note that collection of mushrooms, along with plants and animals, is not permitted on Pound Ridge Land Conservancy preserves except during our guided hikes.  If you would like to join our email list to be notified of future mushroom forays, email PRLC’s land steward or call our office at 914-205-3533.

Thank you to our event participants for the photographs, and happy hunting!

Fomes fomentarius-tinder polypore

Fomes fomentarius-tinder polypore

Ishnoderma resinosum

Mutinus ravenelii,dog stinkhorn

 

 

 

Panellus serotinus, late fall oyster, edible but not choice

Panellus serotinus, late fall oyster, edible but not choice

Under side of Panellus serotinus, late fall oyster, edible but not choice

 

 

 

 

 

 

 

 

 

 

Phlebia radiata

Pholiota sqarrosoides, edible

 

Pleurotus ostreatus, oyster mushroom, choice edible

Pleurotus ostreatus, oyster mushroom, choice edible

Russula xerampelina, edible but not recommended, use caution

Russula xerampelina, edible but not recommended, use caution

underside of Russula xerampelina, edible but not recommended, use caution

 

 

 

 

 

 

 

 

 

 

 

Tyromyces chioneus

Tyromyces chioneus

 

 

 

 

Shall We Go On A Mushroom Hunt?

Mycophile or mycophobe?  Most people fall into one of these two categories, being either mushroom-loving or mushroom-fearing.  European and Asian cultures are generally mycophilic, passing on knowledge of favorite edibles and medicinals, along with hunting grounds for finding them, from generation to generation.  Americans tend to mushroom-phobic, being more concerned with the potential for toxicity, or perhaps simply lacking in knowledge due to the shorter history of our culture.

In this installment of the Living Lighter on the Land blog, I will provide a brief overview of fungal life forms in hopes of inspiring you to take another look, for this is the time of year to find them.  I also encourage you to join our Guided Walk and Talk in search of mushrooms, scheduled for September 21st.  Please email me to register for this free and family-friendly event.

Mushrooms, or fungi, are an exceedingly diverse group of organisms whose taxonomy and biology are bound by certain genetic contraints, which is why they can be described as comprising a kingdom of life.  They are known as the decomposers and are vital to ecological processes such as nutrient cycling. By transforming matter on the molecular level, making it available for trees and plants for example, mushrooms support all life on this planet.

Fungi come in forms both familiar and not, from the molds on our food to the classic polka-dotted parasol to vast networks of underground hyphae or mycelium.  They generally reside in the substrate upon which they eventually “flower,” or more accurately, fruit.  What we see are highly modified extensions of the hyphae which are formed in order to disperse spores, or reproductive cells, into the environment.  In this way, harvesting mushrooms is akin to picking berries from a bush.

Mushrooms can be divided into categories based upon their growth forms, and knowing these groupings is a first step for any budding mycologist:

      Slime molds   Sac Fungi   Puffballs   Jelly fungi   Corals   Bracket Fungi    Boletes   Gilled

Like plants and animals, fungal species have specific habitats and substrates that they are best adapted to and which provide clues to the kinds of fungi we can expect to find.  Most mushroom identification guides include keys to identifying species, and these will include details on growth form and environment, in addition to physical characteristics of the mushroom itself.

When I find a mushroom that I would like to identify, I take immediate note of the following:  the substrate upon which it grows, surrounding trees, fruiting habit (single, scattered, or clumped), and color, odor, and moisture level of the mushroom itself.  At home, the first thing I do is make a spore print: break the cap off (if there is one) and lay it gill- or pore-side down on a sheet of paper.  It works best to use a half black/half white sheet of paper, laying the mushroom down in the center, so that white or black spores show up against the contrasting color of the paper.  It might take a day or more for the spores to drop out.

While I wait, I make note of the following characteristics of the mushroom’s form (a good field guide can help to familiarize you with descriptive terms used for each factor):

cap diameter, shape, edge, surface texture and color

flesh thickness, brittleness, odor, and presence/absence of latex

gill attachment, spacing, color, thickness, depth, and margin

stalk size, shape, texture, color, hollowness, ring structure, cup structure

There is quite a lot of information that goes in to identifying a mushroom to species, and sometimes the differences between them are so subtle that genetic analysis is necessary.  Don’t be discouraged!  The joy of mushrooming is in experiencing the wonder of their ephemeral form and their place in nature.  With practice and the help of other mushroomers, you might one day enter the world of foraging fungi for food and medecine.  I recommend joining on-line groups such as Facebook’s Mushroom Identification Forum, as well as groups that meet in-person for forays, such as the Connecticut Westchester Mycological Assocation (COMA).

All photographs courtesy of the author.

 

Please help us keep dogs on our preserves

prlc_03-11-2014Please help us keep dogs on our preserves – leash your dog!

The Pound Ridge Land Conservancy is committed to allowing dogs on our preserves, but we need you to keep your dog on a leash.     

We have had some incidents that could have been prevented if the dogs had been leashed.  In addition,  dogs going off trails because they are not leashed can cause significant unintentional damage to the plant growth we are trying to protect.   During hunting season (October 1 – December 31), roaming dogs can interfere with deer control efforts as well.    

Your cooperation will enable us to keep our preserves dog-friendly.  

Thank you!

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