Tuesday, March 29, 2022

Episode 622 (3-28-22): Tree Buds and Water

CLICK HERE to listen to episode audio (4:59).

Sections below are the following:
Transcript of Audio
Audio Notes and Acknowledgments
Related Water Radio Episodes
For Virginia Teachers (Relevant SOLs, etc.).

Unless otherwise noted, all Web addresses mentioned were functional as of 3-25-22.


From the Cumberland Gap to the Atlantic Ocean, this is Virginia Water Radio for the week of March 28, 2022.  This revised episode from December 2018 is part of a series this year of episodes related to trees and shrubs.

MUSIC – ~ 10 sec – instrumental.

This week, that excerpt of “Hiking in the Highland Firs,” by Timothy Seaman of Williamsburg, Va., opens an episode on a woody plant structure that’s closed during wintertime and whose opening is a mark of spring.  Have a listen for about 15 seconds to some of the weather that trees and shrubs endure during a Virginia winter, and see if you can guess this structure.  And here’s a hint: if you don’t know this, you might ask a buddy.

SOUNDS  - ~15 sec – March wind in previous year's oak leaves.

If you guessed tree and shrub buds, you’re right!  Buds are one of woody plants’ adaptations for surviving winter’s cold temperatures, drying conditions, and damaging winds.  Buds contain meristematic tissue, the tissue that will be future growing stems or flowers.  Sometimes woody plant buds include only the meristematic tissue, but more typically that tissue is covered by small, folded leaves and modified leaf structures called bud scales.  Just like tree and shrub leaves, buds have distinctive shapes and colors, often allowing identification when leaves are gone.

Flowering trees and shrubs form both vegetative and flower buds.  The vegetative buds can be at the end of twigs or along the length of twigs in the axils where leaves attach.  Flower buds may look very different from vegetative buds, for example, as in the Flowering Dogwood.  Non-flowering trees and shrubs—that is, conifers, the cone-bearing woody plants, such as pines, spruces, and firs—also have vegetative buds that can develop into stems or into cones.

In temperate climates, buds typically form at some point during the growing season and then become dormant—that is, stop actively growing—during the winter.  In spring, in response to hormones and environmental conditions, bud dormancy ends as the buds open and the enclosed tissues begin developing and growing.  But there’s much variation among species, and even among individuals within a species, in patterns and timing of bud formation, dormancy, and activity.

Now, what makes woody plant buds particularly a water story?  Here are three answers to that question. First, the availability of water during bud formation in one year can affect how much tissue is stored in the bud for growth and development the following spring.  Second, the meristematic tissue in a bud is protected from drying out by the covering bud scales and undeveloped leaves.  And third, while buds don’t protect plant cells from freezing, their role in preventing dehydration contributes to the plant’s ability to withstand injury from freezing temperatures.

As spring unfolds in Virginia, some do the buds on the Commonwealth’s woody plants, revealing some of the history—and water—of last summer, along with the future of this year’s growing season.

Thanks to Timothy Seaman for permission to use this week’s music, and we close with about 20 more seconds of “Hiking in the Highland Firs.”

MUSIC – ~ 22 sec – instrumental. 


Virginia Water Radio is produced by the Virginia Water Resources Research Center, part of Virginia Tech’s College of Natural Resources and Environment.  For more Virginia water sounds, music, or information, visit us online at virginiawaterradio.org, or call the Water Center at (540) 231-5624.  Thanks to Stewart Scales for his banjo version of Cripple Creek to open and close this episode.  In Blacksburg, I’m Alan Raflo, thanking you for listening, and wishing you health, wisdom, and good water.


This Virginia Water Radio episode revises and replaces Episode 449, 12-3-18.

“Hiking in the Highland Firs,” from the 2001 album “Common Wealth,” is copyright by Timothy Seaman and Pine Wind Music, used with permission.  More information about Timothy is available online at http://www.timothyseaman.com/.   “Hiking in the Highland Firs,” written in honor of Virginia’s Grayson Highlands State Park, was previously featured in Virginia Water Radio Episode 320, 6-13-16, on Virginia’s state parks.

The sound of wind in oak leaves was recorded by Virginia Water Radio in Blacksburg, Va., on March 15, 2013.

Virginia Water Radio thanks Jen Gagnon, John Peterson, and John Seiler, all of the Virginia Tech Department of Forest Resources and Environmental Conservation, for their help with this episode in 2018 and 2022.

Click here if you’d like to hear the full version (1 min./11 sec.) of the “Cripple Creek” arrangement/performance by Stewart Scales that opens and closes this episode.  More information about Mr. Scales and the group New Standard, with which Mr. Scales plays, is available online at http://newstandardbluegrass.com.


Yellow Buckeye bud opening and leaves emerging in Blacksburg, Va., April 1, 2010.

Sawtooth Oak buds and previous year’s leaves in Blacksburg, Va., March 29, 2022.

White Pine bud among needles in Blacksburg, Va., March 29, 2022.

Tulip Poplar bud opening and leaf emerging in Blacksburg, Va., March 29, 2022.

Spruce bud among needles in Blacksburg, Va., March 29, 2022.

Elm buds opening and leaves emerging in Blacksburg, Va., March 29, 2022.


Paul J. Kramer and Theodore T. Kozlowski, Physiology of Woody Plants, Academic Press, New York, 1979. 

Steven G. Pallardy, Physiology of Woody Plants, Third Edition, Elsevier/Academic Press, Burlington, Mass., 2008.  (This book is a revision of the 1979 work by Kramer and Koslowski listed above.) 

John R. Seiler, John W. Groninger, and W. Michael Aust, Forest Biology Textbook, Virginia Tech, Blacksburg, Va., 2022.  Access requires permission of the Virginia Tech Department of Forest Resources and Conservation, online at https://frec.vt.edu/; phone (540) 231-5483.

Texas A&M University AgriLife Extension, “How Trees Grow,” online at https://agrilife.org/treecarekit/introduction-to-tree-care/how-trees-grow/.

For More Information about Trees in Virginia and Elsewhere

Center for Watershed Protection, “Trees and Stormwater Runoff,” online at https://www.cwp.org/reducing-stormwater-runoff/.

Chesapeake Bay Program, “Field Guide: Plants and Trees,” online at https://www.chesapeakebay.net/discover/field-guide/all/plants_trees/all.

Oscar W. Gupton and Fred C. Swope, Trees and Shrubs of Virginia, University of Virginia Press, Charlottesville, 1981.

Sanglin Lee and Alan Raflo, “Trees and Water,” Virginia Water Resources Research Center, Virginia Water Central Newsletter, pages 13-18, online at https://vtechworks.lib.vt.edu/handle/10919/49367.   (A Virginia Cooperative Extension version of this article—“Trees and Water,” by Sanglin Lee, Alan Raflo, and Jennifer Gagnon, 2018—with some slight differences in the text is available online at https://www.pubs.ext.vt.edu/content/pubs_ext_vt_edu/en/ANR/ANR-18/ANR-18NP.html.)

U.S. Department of Agriculture (USDA) Forest Service, Forests of Virginia, 2018,  Resource Update FS-264, Asheville, N.C., 2020; available online at https://www.fs.usda.gov/treesearch/pubs/59963.

U.S. Department of Agriculture (USDA)/Natural Resources Conservation Service Plants Database, online at https://plants.usda.gov.

Virginia Botanical Associates, “Digital Atlas of the Virginia Flora,” online at http://www.vaplantatlas.org/index.php?do=start&search=Search.

Virginia Department of Conservation and Recreation/Natural Heritage Division, online at https://www.dcr.virginia.gov/natural-heritage/.

Virginia Department of Forestry, “Virginia’s Forests,” online at https://dof.virginia.gov/.  Some of the useful pages at that site are the following:
“Benefits of Trees,” online at https://dof.virginia.gov/education-and-recreation/learn-about-education-recreation/benefits-of-tree/;
“Common Native Trees of Virginia,” 2020 edition, online (as a PDF) at https://dof.virginia.gov/wp-content/uploads/Common-Native-Trees-ID_pub.pdf;
“Trees for Clean Water Program,” online at https://dof.virginia.gov/urban-community-forestry/urban-forestry-community-assistance/virginia-trees-for-clean-water-grant-program/;
“Tree Identification,” online at https://dof.virginia.gov/education-and-recreation/learn-about-education-recreation/tree-identification/.

Virginia Native Plant Society, online at http://vnps.org/.

Virginia Tech Department of Forest Resources and Conservation, “Virginia Tech Dendrology” online at https://dendro.cnre.vt.edu/dendrology/vtree.htm.  At this site, one can search for trees by common or scientific name.

A.S. Weakley, J.C. Ludwig, and J.F. Townsend, Flora of Virginia, Bland Crowder, ed.  Copyright by the Foundation of the Flora of Virginia Project, Inc., Richmond.  Botanical Research Institute of Texas, Fort Worth, 2012.  This is the first comprehensive manual of Virginia plants published since the 1700s.  The Flora of Virginia Project is online at https://floraofvirginia.org/.


All Water Radio episodes are listed by category at the Index link above (http://www.virginiawaterradio.org/p/index.html).  See particularly the “Plants” subject category.

Following are links to other episodes on trees and shrubs [good as of Episode 621]

Introduction to trees and water – Episode 621, 3-21-22.
American Sycamore – Episode 176, 8-26-13.
American Witch Hazel – Episode 238, 10-31-14.
Ash trees – Episode 376, 7-10-17.
Early spring wildflowers in woodlands – Episode 573, 4-19-21.
Forestry as work and as an industry in Virginia – Episode 160, 5-6-13.
Maple trees – Episode 503, 12-16-19.
Photosynthesis – Episode 602, 11-8-21.
Poison Ivy and related plants, including the shrub Poison Sumac – Episode 535, 7-27-20.
Rhododendrons – Episode 574, 4-26-21.
Tree colors and changes in fall, including to water movement – Episode 285, 10-9-15.


Following are some Virginia Standards of Learning (SOLs) that may be supported by this episode’s audio/transcript, sources, or other information included in this post.

2020 Music SOLs

SOLs at various grade levels that call for “examining the relationship of music to the other fine arts and other fields of knowledge.”

2018 Science SOLs

Grades K-4: Living Systems and Processes
K.7 – Plants and animals have basic needs and life processes.
1.4 – Plants have basic life needs (including water) and functional parts that allow them to survive; including that plants can be classified based on a variety of characteristics.
2.4 – Plants and animals undergo a series of orderly changes as they grow and develop, including life cycles.
2.5 – Living things are part of a system.
3.5 – Aquatic and terrestrial ecosystems support a diversity of organisms.
4.2 – Plants and animals have structures that distinguish them from one another and play vital roles in their ability to survive.\
4.3 – Organisms, including humans, interact with one another and with the nonliving components in the ecosystem.

Grades K-5: Earth and Space Systems
K.9 – There are patterns in nature.
1.7 – There are weather and seasonal changes; including that changes in temperature, light, and precipitation affect plants and animals, including humans.
2.7 – Weather patterns and seasonal changes affect plants, animals, and their surroundings.
4.4 – Weather conditions and climate have effects on ecosystems and can be predicted.

Grades K-5: Earth Resources
2.8 – Plants are important natural resources.
4.8 – Virginia has important natural resources.

Grade 6
6.6 – Water has unique physical properties and has a role in the natural and human-made environment.

Life Science
LS.3 – There are levels of structural organization in living things.
LS.7 – Adaptations support an organism’s survival in an ecosystem.
LS.8 – Change occurs in ecosystems, communities, populations, and organisms over time.

BIO.6 – Modern classification systems can be used as organizational tools for scientists in the study of organisms, including that organisms have structural and biochemical similarities and differences.

Virginia’s SOLs are available from the Virginia Department of Education, online at http://www.doe.virginia.gov/testing/.

Following are links to Water Radio episodes (various topics) designed especially for certain K-12 grade levels.

Episode 250, 1-26-15 – on boiling, for kindergarten through 3rd grade.
Episode 255, 3-2-15
– on density, for 5th and 6th grade.
Episode 282, 9-21-15
– on living vs. non-living, for kindergarten.
Episode 309, 3-28-16
– on temperature regulation in animals, for kindergarten through 12th grade.
Episode 333, 9-12-16
– on dissolved gases, especially dissolved oxygen in aquatic habitats, for 5th grade.
Episode 404, 1-22-18
– on ice on ponds and lakes, for 4th through 8th grade.
Episode 407, 2-12-18
– on snow chemistry and physics, for high school.
Episode 483, 7-29-19
– on buoyancy and drag, for middle school and high school.
Episode 524, 5-11-20
– on sounds by water-related animals, for elementary school through high school.
Episode 531, 6-29-20
– on various ways that animals get water, for 3rd and 4th grade.
Episode 539, 8-24-20
– on basic numbers and facts about Virginia’s water resources, for 4th and 6th grade.
Episode 606, 12-6-21
– on freezing and ice, for kindergarten through 3rd grade.