George Mason’s Virginia Climate Center Releases First-ever Statewide Climate Assessment

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Cover of the First Virginia Climate Assessment, Virginia Climate Center–George Mason University

George Mason University’s Virginia Climate Center (VCC) has unveiled the commonwealth’s first comprehensive, peer-reviewed climate assessment—a landmark report that provides science-based insights into Virginia’s changing climate and its impacts on communities, infrastructure, and the economy. 

This report marks the inaugural comprehensive assessment of climate conditions across the Commonwealth of Virginia. While Virginia’s diverse weather and climate patterns have been examined in both local and broader national and global contexts, no prior effort has synthesized the wealth of scholarly research specific to Virginia into a unified resource.

The Virginia Climate Assessment provides a science-based evaluation of the ways past, current, and anticipated climates have and will impact Virginia and its people. As the first report of its kind for the state, it provides a collection of evidence-based key messages that have been prepared and extensively reviewed
by technical and scientific experts across Virginia and beyond. It is expected to be the first in a series of such assessments, establishing a baseline against which future changes and impacts can be measured and understood, and adaptation effectiveness and resilience can be evaluated.

READ THE FULL REPORT

An executive summary for busy readers and the VCA’s top findings.

KEY MESSAGES

1. Virginia’s climate is shaped by weather patterns stemming from higher and lower latitudes, while regional variation reflects topography and coastal
proximity (high confidence).

2.The Virginia climate has become warmer (very high confidence) and wetter (medium confidence) in recent decades, with greater precipitation extremes
(high confidence) and more frequent tidal flooding (very high confidence) along the Atlantic coast.

3.Climate projections indicate continued warming (very high confidence) and wetting (medium confidence) for Virginia through the middle to late 21st century, with chronic tidal flooding along the Atlantic coast (very high confidence).

The Virginia Climate Assessment is intended to be used to inform climate adaptation plans, resilience strategies, and policy decisions, and provide evidence for developing targeted responses to climate impacts. Key Messages can be used to identify areas of critical need for strategic planning, provide supporting evidence for budget proposals, and outline potential directions for policy development or climate action planning.

DWR Asking Public to Report After Increase in Suspected Cases of Avian Influenza

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Photo: Joe Subolefsky – Black Vultures./Audubon Photography Awards

PRESS RELEASE: RICHMOND, VA

The Virginia Department of Wildlife Resources (DWR) has recently received reports of groups of dead black vultures across the state including several counties in Southwest Virginia. Preliminary testing indicates that the likely cause is H5N1 highly pathogenic avian influenza (HPAI). Although disease activity is currently centered in black vultures, with migration season beginning, it is likely there will be mortalities in other bird species as well.

DWR asks that if you observe any of the following, please notify the Department by calling the Virginia Wildlife Conflict Helpline at 1-855-571-9003 or emailing wildlifehealth@dwr.virginia.gov.

  • �� Five or more dead vultures, waterfowl, shorebirds, or seabirds in the same area within five days
  • �� Sick or dead eagles, hawks, owls, or turkeys, excluding ones found on the road
  • �� Ten or more dead wild birds of any species in the same area within five days

The public is advised to avoid picking up or handling sick or dead wild birds. If you must dispose of a dead bird on your property, wear rubber gloves and other personal protective equipment, such as a mask and eye protection. Dead birds should be buried or double bagged and disposed of in a secured outdoor trash can or landfill. After disposing of the carcass, wash hands thoroughly with soap and water or use an alcohol-based hand sanitizer, and disinfect clothing, and shoes. If you are frequently in contact with poultry, including backyard flocks, or other domesticated birds, you are encouraged to have separate clothing and shoes for use in the areas where you keep those birds. In addition, keep flocks away from vultures and ponds or similar bodies of water that are also accessible to wild waterfowl. Taking these precautions will help reduce the risk of spreading the virus.

If you develop any flu-like symptoms after handling wild birds (fever, body aches, red or itchy eyes, etc.), contact your state or local health department.

More information on Avian Influenza can be found on the Virginia DWR website.

Article Review: “Ospreys May Be in Trouble Again”, Article by Glenda C. Booth

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Photo: By Glenda Booth, Osprey and their young at the Belle Haven Marina platform nest on June 18, 2025. 

This complete article by Glenda C. Booth appeared in the July 17th edition of the Alexandria Gazette Packet:                       https://www.alexandriagazette.com/news/2025/jul/17/ospreys-may-be-in-trouble-again/

Glenda C. Booth’s article, “Ospreys in Northern Virginia,” is a well-crafted and engaging piece that combines local wildlife reporting with broader environmental concerns. Ms. Booth effectively relates scientific insights and on-the-ground observations from concerned community members to illustrate the troubling decline in osprey populations across Northern Virginia.  She describes the breeding observations at nesting sites like Dyke Marsh and Porto Vecchio. She also mentions potential stressors to breeding success —such as fish shortages, climate change, habitat loss, and commercial menhaden harvesting. The article makes complex ecological issues understandable. Ms. Booth’s article is informative and timely. It surely raises awareness about the challenges ospreys face and the broader environmental implications behind their struggles.

Article Review: “For the First Time in Decades, Hikers Can Walk in Forests of Mature, Wild American Chestnuts” Article by By Eric Wallace

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Eric Wallace’s Article: “For the First Time in Decades, Hikers Can Walk in Forests of Mature, Wild American Chestnuts”, published in the July 24, 2025, Garden & Gun: Article Link

Eric Wallace’s article is a well-written and inspiring piece that effectively highlights a significant ecological achievement—the partial restoration of the American chestnut. It balances historical context, scientific detail, and emotional appeal.

For the first time in nearly a century, hikers can once again walk through mature forests of wild American chestnut trees, thanks to long-term conservation efforts. Once known as the “redwood of the East,” the American chestnut dominated forests from Mississippi to Maine, offering durable wood and abundant nuts. However, a devastating fungal blight introduced in the early 1900s wiped out nearly all mature trees within a few decades, rendering the species functionally extinct.

In response, the American Chestnut Foundation (ACF) and its partners spent decades developing blight-resistant hybrids by crossbreeding American chestnuts with Asian varieties and then backcrossing to retain the original tree’s genetics. These efforts are now bearing fruit—literally and figuratively—with sites like Lesesne State Forest in Virginia hosting 60-year-old, 70-foot-tall chestnut trees that are once again producing nuts.

Today, visitors can hike through several restored chestnut groves across Virginia, including Matthews State Forest, Sky Meadows State Park, and Mountain Lake Wilderness. The trails range from two to four miles and offer a rare opportunity to witness the rebirth of a species that once seemed lost. This resurgence of the American chestnut is more than a conservation victory—it’s a hopeful sign that damaged ecosystems can be healed with persistence and science.

Article Review, “Dyke Marsh: A Fragile Treasure” by Glenda C. Booth, President, Friends of Dyke Marsh

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Photo by Ned Stone, A Dyke Marsh inlet.

Article: “Dyke Marsh: A Fragile Treasure”, published in the July 14, 2025, Northern Virginia Bird Alliance News:  https://www.nvbirdalliance.org/news/dyke-marsh-a-fragile-treasure

Glenda Booth’s article presents a thorough overview of Dyke Marsh’s ecological importance, biodiversity, history of degradation, and current restoration efforts.

Dyke Marsh, part of the George Washington Memorial Parkway and overseen by the NPS, is one of the largest tidal freshwater marshes remaining in the Washington, D.C. area—some parts are over 2,200 years old. It is a vital habitat supporting over 230 bird species and a rich variety of plants and wildlife. This area delivers vital ecological services such as flood mitigation, water purification, and biodiversity support.

Once damaged by decades of dredging, it has faced severe erosion, invasive species, and pollution. Restoration efforts, including a breakwater and shoreline stabilization, aim to reverse the damage. The Friends of Dyke Marsh (FODM) actively support conservation through invasive species removal, wildlife monitoring, and public education. Despite its fragility, Dyke Marsh remains a valuable natural refuge for both wildlife and visitors.

Dyke Marsh stands as a rare and vital natural habitat in the D.C. region—rich in biodiversity and ecological function, yet under serious threat from past dredging, ongoing erosion, invasive species, and human disturbance. Thanks to significant funding, restoration actions, and volunteer efforts by FODM, there is hope for its recovery and continued benefit for wildlife and people.

Biodiversity or Mosquito Fogging: You can’t have both

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Article and photo by Plant NOVA Natives

Ah, the mosquito. It plagues our summers and can ruin our outdoor fun. Is anyone a fan? If so, consider the Asian tiger mosquito, which has no regard for personal space or time. If you happen to have it in your yard, it bites everyone, morning, noon, and night. In winter we long for warm weather, but when it finally arrives, in some neighborhoods we are indoor prisoners. Understandably we want to rid ourselves of this awful pest.

Some of our neighbors turn to commercial-grade mosquito fogging, persuaded by marketing claims that the product is both effective and “safe”. But a closer examination of these claims reveals an ineffective process that is devastating for native bees, butterflies, moths, and a plethora of other beneficial insects we work so hard to attract with native plants.

How effective is mosquito spraying? How effective can it be when the chemicals in the product only target adult mosquitos and only those adults within direct range of the fog? By some estimates, no more than 20-30% of adult mosquitos are killed in one treatment. Meanwhile all mosquito larvae, which are laid and hatched in standing water, are unaffected. They continue to grow and emerge as if nothing harmful has happened in their environment. As a result, the adult population of mosquitos is quickly replenished while nearly every other insect the fog touches is indiscriminately killed.

Mosquito spray producers point to EPA statements that the chemicals are safe for bees when used according to label instructions. But there are severe limitations to the EPA’s testing method. The agency only tests on honeybees and only measures the chemical toxicity resulting from surface exposure, not oral ingestion.

This is highly problematic. Honeybees are only one species of bees and are non-native to boot. That leaves 400 species of native bees in Virginia, along with all butterflies, moths, dragonflies, ladybugs, fireflies, and numerous other beneficial insects that are not tested. Those insects have entirely different life cycles, foraging methods, and ways of protecting and feeding their larvae which render them tragically vulnerable. It is a complete folly to extrapolate EPA’s honeybee-focused test results to any other insect species.

Consider this: One spray of mosquito fog leaves a persistent residue on the surface of everything it touches. Repeating the applications every 10-30 days, as many commercial services recommend, just compounds the problem. The EPA says it considers how long the chemical residue persists in the environment and its effect on honeybee colonies. However, honeybees can forage up to 5 miles away from their hives if necessary, far away from the fogged area and the residue. Our native mason bees, on the other hand, forage no further than 300 feet from their nests. They are wholly dependent on the health of their immediate surroundings to eat and reproduce. Adults have no way to avoid exposure.

Neither do their larvae. Leaf cutter bees and mason bees, for example, produce dough balls that are left in hollow stems for their developing larvae to eat. The balls are composed of pollen and nectar from the flowers in their immediate foraging range. As the larvae hatch and eat the dough balls, they ingest concentrated levels of the pesticides and die. For our native bees, there is no honeybee equivalent of the hive to ensure their survival. They live their lives alone. As their larvae die, all subsequent lines of offspring from affected individuals are gone for good.

Fortunately, as research has advanced on fogging, so too has the thinking on several alternative, inexpensive methods of control. Here are some very safe and effective suggestions, especially when used together as a suite of tools.

Source Removal. The most effective method of mosquito control by far is “source removal,” or emptying/eliminating all sources of standing water on your property. This practice kills mosquito larvae before they become biting adults. Regularly inspect your property for containers or areas that hold water, then remove or empty them. Remember to inspect flowerpots, buckets, or any other feature or item that can hold water. Change the water frequently in places where you want it – like birdbaths – so the larvae have no time to grow and emerge. Maintain your gutters and downspouts so the water flows. Keep your swimming pools and hot tubs clean and properly chlorinated.

Mosquito Buckets: This is a favored method of control by Doug Tallamy, an entomologist at the University of Delaware and national proponent of supporting biodiversity in our own backyards. He recommends filling a five-gallon bucket of water, placing it in the sun, then adding a handful of hay, grass, straw, or leaf litter to decay and attract egg-filled female mosquitos. After they lay their eggs, add a mosquito dunk tablet you can purchase at any hardware store, garden center, or home improvement retailer. It contains a bacteria that kills several species of fly larvae, including mosquitoes. A more detailed explanation of the process – and photos of lovely painted buckets –  can be found on Dr. Tallamy’s Homegrown National Park website.

Ovitraps: Ovitraps, which are available from the same stores as mosquito dunks as well as on Etsy, use scent to attract adult egg-laying females, trap them, and kill both the adults and the larvae they produce.   

Water Wrigglers: Water Wrigglers are devices you can purchase to keep water moving in birdbaths. They were designed to attract birds to the sight and sound of running water but are also highly effective in stopping female mosquitos from laying eggs.

Deck Fans: Mosquitos are weak fliers. Turn on a fan while you enjoy your deck and make it harder for mosquitos to reach you.

Personal Protection: When spending time outdoors, consider wearing long pants, sleeves, and a hat, and spraying your clothing and skin with insect repellant. Personal precautions such as these can prevent mosquito bites entirely.

Community Efforts: Mosquito control is very successful when several neighbors in a larger community participate. Talk to your neighbors about source removal, ovitraps, fans, and water wigglers. Show them your homemade mosquito bucket and encourage them to do the same – or bring them one as a gift! Some studies tout this approach above all others, suggesting that mosquito populations can be reduced by 85% when the whole street or block works together. One way to approach your neighbors is by inviting them to join a Pollinator Pathway and giving them a nifty little sign to display which will encourage other neighbors to rethink their mosquito-spraying contracts.

We all enjoy our yards and our pollinator gardens, and we understand how including native plants promotes biodiversity. But along with joy comes responsibility. If we don’t protect the very life we’ve helped emerge, no one will. We can have improved biodiversity, or we can have pesticides. They do not co-exist.

 

The Grist Mill at Colvin Run Mill Park

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Feature photo: Fairfax County Park Authority

Article and other photos by FMN Stephen Tzikas

Just off Route 7 in Great Falls, Virginia, is a rare working grist mill from the early 19th century. The Colvin Run Mill campus is part of the Fairfax County Park Authority, and is an opportunity to see nature and engineering working together.  Grist mills offer the opportunity to observe engineering principles related to powder technology in a park setting.  In 2002, my first visit to a mill, known as Evins Mill, coincided with a chemical engineering course on powder processing I attended in Tennessee. The instructor wrote the Size Reduction and Size

Close up of the water wheel

Enlargement chapter in Perry’s Chemical Engineering Handbook. The simple grist mills of the past represented the beginnings of powder technology engineering. Powders are used in a variety of industries including the pharmaceutical, consumer products, food and industrial chemical sectors.  The handling of powders requires a knowledge of properties related to particle size, moisture sorption, surface area, surface chemistry, hardness, density, and flowability. Operations include segregation and powder sampling, as well as key unit operations of mixing, grinding, agglomeration, classification, fluidization, drying and compaction, as well as solids transport between unit operations.

The grinding unit

The Colvin Run Mill is powered by a 20-foot waterwheel. The use of elevators, moving belts, and Archimedean screw conveyors made the milling operation more efficient and profitable, as an early example of mass production. The wheel’s axle transmits power from the turning waterwheel into the mill. The greater face gear attached to the axle in the mill basement turns the wood gears that operate the grinding stones, grain elevators, and sifting machinery. The waterwheel produces up to 26 horsepower, turning (outside) at a rate of 10 rpm, resulting in a top grindstone rate of 100 rpm.  Premium burr stones were imported from France to grind the grain.

The tour of the mill’s four floors includes the main grinding floor, the

The racker unit, which cools the powder and prevents its caking

basement, the gear pit, and other processing units. The mill offers the ability to load, convey, sift, grind, separate and dry grain into various desired grades. Each of the four floors of the building served a specific function in turning the grain into flour or cornmeal.

The engineering processes seen at the Colvin Run Mill tour will include:

  • Gears: Falling water moves the water wheel and all gears throughout the mill’s operation. The speed of the water wheel can be adjusted, thereby controlling the speed of the
  • Lever: A beam scale weighs grain from farms. A receiving hopper gathers the grain.
  • Pulley: Pulleys move grain upstairs for cleaning. The grain flows down a chute where it is captured by cups, and transported to the top floor and emptied into another chute.
  • Screens: Screens remove dirt, seeds, sticks, straw, chaff, fungus, smut, broken grains, and bugs. Shaking shifts the grain.  There are different size mesh screens for final processing of the milled grain.  They range in size from super fine to coarse.
  • Inclined plane: A inclined plane sends the cleaned grain to the grinding operation.
  • Grinding: Special French millstones mill the wheat. A screw lifts the mill stone into place for grinding. Wedges line the millstone where they grind the grain. These special French millstones are fossils called burr stones. They rip and shred the grain.  Shafts in the stones move the grain to the next operation.
  • Raking:  Since crushing the wheat generates heat and warms the grain powder, rakes (known as hopper boys) help cool the wheat and prevent caking and clumping

 

Beech Leaf Disease (BLD)

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Photo: Courtesy of FCPA, Beech Leaf Disease observed in Burke Lake Park

The following Information comes from the Urban Forest Management Division Annual Report Fiscal Year 2024, Released April 2025

Beech Leaf Disease (BLD)

What is it?
BLD, a relatively new disease of native American beech as well as other
Fagus/beech species, is caused by a foliar-feeding nematode (a
microscopic roundworm). The nematodes enter the tree’s leaf buds in
the fall where they overwinter, multiply, and feed on newly forming
leaf tissues. The nematodes further multiply and spread throughout
the tree from year to year until leaf buds no longer produce leaves.
As healthy foliage decreases, the tree’s energy, nutrient, and water
uptake decreases, and the tree eventually dies.
Why is it a problem?
Beech trees are critical to the native forest ecosystem, providing
food for a wide variety of wildlife, and bearing nutrient-rich fruit with
seeds that last through the winter and serve as a food source when
other plants have long stopped producing. There are approximately 4.3
million beech trees in Fairfax County, making them tied with red maple
for the County’s most common tree species. BLD, nearly 100% fatal,
is spreading rapidly; and there is no known safe treatment option for
forested environments.
What is being done?
County staff achieved the following results and milestones in FY 2024:
 Mapped 6 infestations totaling 60 acres at regional and County parks (previously 13 acres in FY 2023).
 Established 4 monitoring plots in beech stands confirmed to have, or at high risk of developing, BLD.
 Participated in a comprehensive U.S. Department of Agriculture (USDA) Forest Service study spanning the full geographic reach of
both BLD and beech bark disease.
 Hosted a webinar—“Unraveling the Mystery”—in partnership with Virginia Cooperative Extension (VCE) to raise awareness.
 Contributed BLD samples for a regional nematode DNA study out of the University of Connecticut.
How YOU can help!
– First, learn to IDENTIFY early symptoms of the disease, infected leaves, and other diseases that can appear like BLD.
– REPORT sightings on iNaturalist, an easy-to-use app that shares information with community scientists.
– And finally, PRACTICE good tree care such as proper mulching and watering during droughts; and be considerate and responsible when it
comes to selecting soil treatments and other landscaping services.

This report is in PDF format which allows you to search for other pest like the hemlock woolly adelgid, and the spotted lanternfly..

 

Pollinator Pathways: Connecting your yard to the bigger picture

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Photo: Plant NOVA Natives

Article by Eileen Ellsworth

Imagine the world as it once was. Verdant forests, buzzing meadows, and numerous other natural areas were immense, whole, and pulsing with life. Over time, human activity emerged and carved the natural world into disconnected, even isolated parts. Ecologists refer to this process as habitat fragmentation. You can see it in urban settings where green parks are biological islands surrounded by buildings and concrete roads. You can see it in rural settings where agriculture simplifies ecosystems and amplifies the populations of only certain insects to the detriment of others. You can see it in suburban settings where developments destroy natural habitats and where landscapes are “replaced” with all non-native species.

Large and mostly undisturbed ecosystems can still be found, of course, especially in our beloved national parks and forests. But even they are distant from each other, understaffed, and too small in total acreage to sustain the biodiversity of the continent. Any solution to the problem of habitat fragmentation and the resulting loss of biodiversity, therefore, must be found right here among the throng of human life – where we live, work and play.

Is it possible to reconnect isolated fragments in our urban, suburban, and rural settings to benefit pollinators and the creatures that depend upon them? That was the question that sparked the “pollinator pathway” concept in 2007 by Sarah Bergmann, an artist living in Seattle. As part of a social and ecological project, she envisioned and described a network of native gardens that could create a “pathway” to support pollinators. This core idea led to the creation of a nonprofit – Pollinator Pathway – by Donna Merrill, a conservationist from Wilton, Connecticut, in 2017. Since then, the group has helped inspire and launch a national movement.

The idea is a powerful one. Anybody can take part, even at a novice level. There are very few barriers to participation. If all you have is one native tree or a  small pollinator garden – preferably one with some native plants – it’s a start, and you can build from there.

The main goal of a pollinator pathway is to reinstate connectivity between several small but healthy habitats. A single native tree can support bees and other pollinators as much if not more than a flower garden. Building a pollinator pathway on your street, for example, may include adding a new native tree or two, or creating new healthy gardens on communal grounds or private property as “stepping stones” along the way. It may include the expansion of existing native plant areas. Removal of invasives that disrupt the pathway will certainly be part of the plan, along with pledges to avoid all broadcast pesticides including mosquito and tick sprays. Only unpoisoned ecosystems can be included in the work.

Many communities across America are already building pollinator pathways and proving the concept. You can recruit participants on your own, or have fun working with like-minded people to muster engagement. Hold a kick-off meeting to build some early momentum. Don’t over plan. Take some early action, starting with 1 or 2 easy planting projects, then see where it takes you.

On a new webpage just launched by Plant NOVA Natives you will find some handy tools to help you build a pollinator pathway in your neighborhood or community. They include:

  • A tip sheet for pollinator pathway organizers
  • Instructions for ordering medallion signs that will be delivered to your house from Plant NOVA Natives for you and your participants. If you are in Northern Virginia, we will have the sign company mail you the first five for free.
  • Ideas for how to pitch the idea to the folks you want to engage
  • Pollinator Pathway handouts to leave with your neighbor.

Join the movement! Let’s work with our neighbors and friends to connect the fragments, rebuild some beneficial habitats, and heal the everyday ecosystems that surround us. Their resilience is astonishing. New life, activity, and hope will certainly emerge, along with a new joy in being part of something much bigger than our own backyards.

“Distillation” on the Trail

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Charcoal Trail Greenstone Outcrop at Catoctin Mountain Park

Article, photos & illustration by FMN Stephen Tzikas

A few months ago, I prepared a roadside chemical engineering field trip to the Catoctin Iron Furnace in Maryland, for the local chapter of the American Institute of Chemical Engineers.  One of the features on that excursion was a discussion of nature’s “distillation column.” While chemical engineers study distillation at university, nature has its own type of “distillation column.”

The Bowen Reaction Series

Geologists call it the Bowen Reaction Series. The Bowen Reaction Series is a set of reactions that occur when molten igneous rock cools, usually on its way to the surface.  These reactions can be rather gradual (“continuous”) or abrupt (“discontinuous”). Virginia has many igneous rocks, often delivered to the surface as a consequence of past orogenies, or mountain building collisions with land masses off the East Coast, over the period of the last billion years.  Locally, one can find igneous rocks at Great Falls Park and its museum, as well as the outside massive rock collection surrounding the property of USGS in Reston.

A little further west and north of Fairfax County is mountainous terrain.  One finds a lot of greenstone, such as the old greenstone lava flows of Shenandoah National Park, or those rocks of Catoctin Mountain Park. Greenstone, a term for dark green metamorphic rocks, is primarily composed of altered mafic igneous rocks like basalt and gabbro. These basalt and gabbro rock textures would likely have olivine, pyroxene, and calcium plagioclase in them.  When these rocks underwent metamorphism, secondary minerals formed like chlorite, actinolite, and epidote, contributing to the green color.  Specifically, about 500 million years ago molten lava rose up through fissures on the Earth’s surface creating the igneous rocks like basalt. Through metamorphic processes that occurred afterwards, this rock was transformed into metabasalt greenstone.  Hence, the greenstone you will see all around at nearby Catoctin Mountain Park is a result of “natural distillation” processes initially originating from the Bowen Reaction Series.

Charcoal Trail Greenstone Rock Samples at Catoctin Mountain Park

Felsic and mafic rocks are two main types of igneous rocks.  Basalt and gabbro rocks are known as mafic rocks.  A mafic mineral or rock is a silicate mineral or igneous rock rich in magnesium and iron. Most mafic minerals are dark in color, and common rock-forming mafic minerals include olivine, pyroxene, amphibole, and biotite. Mafic rocks often also contain calcium-rich varieties of plagioclase feldspar. Basalt is an extrusive rock, while gabbro is intrusive. Extrusive rock refers to the mode of igneous volcanic rock formation in which hot magma from inside the Earth flows out onto the surface as lava or explodes violently into the atmosphere to fall back as pyroclastics. In contrast, intrusive rock refers to rocks formed by magma which cools below the surface.

At the other end of nature’s “distillation column,” we find felsic rocks, such as granite, that are high in light-colored minerals, including feldspar and quartz.  They are high in silica (SiO2), while mafic rocks are low in silica.  Felsic rocks are also enriched in the lighter elements such as silicon, oxygen, aluminum, sodium, and potassium.