ALLEGHENY NATIONAL FOREST
Elk - Forest - McKean - Warren
EARTHCACHE REQUIREMENTS
Each cacher must send his/her own answers BEFORE logging a find. ... "Geocachers must complete the tasks before they log the EarthCache as found." (4.3. EarthCache logging tasks)
Enjoy the journey (learning adventure) as well as the destination (smiley earned). Remember to take only pictures and leave only footprints. To get credit for this Earthcache, complete the following tasks:
ANSWERS ... SEND ALL ANSWERS VIA MESSAGE
LOG ... INCLUDE THREE ON-SITE VERIFICATION PICTURES ... Westline / Corydon / Discovery
WESTLINE
There are four rocks at this site. Answer from left to right. This site shows common examples.
1a. MESSAGE …. a. Number of tap roots. (Based on the number of trunks on the rock) / b. In addition to tree roots, describe other examples of Biological Weathering that is taking place here. Vascular (flowering plants) and Nonvascular (moss, lichens, ferns) / c. Look at the bare rock vs rock covered with vegetation. This comparison is your percentage. Based on the percentage of Biological Weathering occurring on each rock, which one is experiencing the greatest impact?
1b. LOG ... Post a picture of you or your signature item at or near the coordinates.
CORYDON
This site shows a unique example.
2a. MESSAGE …. a. Number of tap roots. (Based on the number of trunks on the rock) / b. In addition to tree roots, describe other examples of Biological Weathering that is taking place here. / c. What is unusual about this tree-rock that is not evident in most others? / d. Explain how this tree-rock formed? / e. Based on the unusual relationship between this tree and rock, hypothesize whether this will increase or decrease weathering of the rock.
Interesting note from my reviewer ... Is the tree raised above the rock because the roots elevated it, or, in Pennsylvania, is it possible the tree originated from a nurse tree? In the temperate rain forests of Alaska, when a cedar or hemlock tree falls, new trees will start to grow from the fallen tree which eventually rots away, leaving the tree trunk elevated above the ground standing on its roots
2b. LOG ... Post a picture of you or your signature item at or near the coordinates. Do not include any spoilers.
DISCOVERY ROCK
The pictures on this cache page show both commonly found examples, as well as unusual examples. Four are from the ANF, and three are from our travels outside the ANF.
3. LOG ... Discover a rock-tree you think is amazing. a. What type of biological weathering is occurring here? (tree roots, vascular, nonvascular) / b. Post a picture of you or your signature item -and- give the location of the tree-rock you discovered.
OPTIONAL - Please respect the time and effort involved in finding and creating this earthcache by adding A and B to your log.
A. JOURNEY OF THE MIND ... Science explains what we observe. Relate (in your own words) something you found interesting in the reading. This adds to your learning adventure and your log.
B. JOURNEY OF THE HEART ... Art shares our personal experience of what we see. Share something special you found on site, and why it is special to you ... prose / story / poem / picture. This is a memorable addition to your log and will make other hearts smile.
Journeys of Heart and Mind ...
Stories to Touch the Heart and Puzzles to Challenge the Mind / Rainbow Tree Story
Thank you Bradford Ranger Station for all your help.
ROCK TREES IN THE ALLEGHENY NATIONAL FOREST
Due to weathering, soil is continually being formed. Consequently, when soil finds its way into cracks in rock surfaces, plants take hold. There are countless examples of trees, both large and small, growing out of rocks.
"Some 445 million years ago, what is now the Allegheny National Forest was submerged beneath a shallow, inland sea. Over time, weathered material eroded from ancient mountains in eastern Pennsylvania and filled in the sea floor. These deposits left large rocky outcrops, known as Olean conglomerates, which are seen throughout the Allegheny National Forest today. Mud and sand was also deposited, burying microscopic marine life and creating the rich oil deposits by which Pennsylvania would later become so well known." ANF
NURSE TREES / STUMP TREES / ROCK TREES
Nurse Tree is the name given to a tree that has survival value to smaller plants of the same or different species by providing protection from sun, wind and other sources of potential mortality. Stump Tree is the name given by the ANF for trees that fall over and new trees grow out of the stump. A common Stump Tree is Hemlock (State Tree), which provides support and habitat for animal life when it falls. Rock Tree is the name given by CO to describe trees that are growing atop a rock. This is possible by biological weathering, which can be caused by the seedling's root growing into the cracks of the boulder. As they grow bigger, the roots push open the cracks and make them wider and deeper, allowing the tree to grow. To begin this process, soil (even a small amount) needs to be be present. Soil accumulates in the depressions and cracks allowing growth of the tree.
SOIL FORMATION
The formation of soil happens over an extended period of time, often more than 1000 years. Soil is formed from the weathering (breaking down) of rocks and minerals. The surface rocks break down into smaller pieces and is then mixed with organic matter (decaying plants and animals). Over time this creates a thin layer of soil and continues until the soil is fully formed. The soil then supports a large variety of different plants.
WEATHERING
Weathering is the breaking down of rock into smaller fragments. All rock weathers over time. Grains of sediment fall out. Cracks develop on the surface and deep inside. Weathering causes rocks to fracture, buckle, and crumble into soil and sediment. There are two types of weathering - mechanical and chemical.
Mechanical weathering breaks apart rocks without changing their chemical composition. Each fragment and particle weathered away by a mechanical process retains the same characteristics as the original rock. Mechanical weathering can be caused by growing plants, expanding ice, lightning, and expansion and contraction with heating and cooling. These physical processes create enough force to break rocks into smaller pieces.
Chemical weathering occurs when water, air, and other substances react with the minerals in rock. In chemical weathering, the composition of the rock changes.
BIOLOGICAL WEATHERING
Living organisms contribute to mechanical weathering through the growth of roots or the burrowing of animals. Tree roots grow into cracks and joints, increasing the surface area for continual weathering by plants, wind, and water. Plants give off organic acids as part of their life and decay processes. These acids help to break down rocks chemically. Decaying remains of dead animals in soil may form organic acids which, when dissolved in water, cause chemical weathering.
VASCULAR PLANTS (larger and grow out from the rocks)
Plant roots and seedlings sprouting in a crevice exert physical pressure as well as providing a pathway for water and chemical infiltration. The evidence that some soil is present is found in the plants which appear to be growing "out" of the rock. In reality, these plants have roots that are growing in soil that is located in the cracks of the rock.
TREE ROOTS
The function of roots of all types is to both provide water and nutrients, and to anchor the tree in the soil, balancing the upper growth. Tap roots extend from the bottom of the tree, then stop growing. Diagonal heart roots and lateral feeder roots take over from the tap root.
NONVASCULAR PLANTS (smaller and cover surface of rocks)
Lichens and mosses grow on essentially bare rock surfaces and create a more humid chemical microenvironment. The attachment of these organisms to the rock surface enhances physical as well as chemical breakdown of the surface microlayer of the rock.
ANIMALS
Burrowing animals and insects disturb the soil layer adjacent to the bedrock surface thus further increasing water and acid infiltration and exposure to oxidation processes.
RESOURCES ... Biological Weathering ... Tree Roots ... Tree Roots
THANK YOU
Sun and Earth for your many gifts.
Universal Tree
