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Invasive Plants - page 3
Within every ecosystem, niche, or natural environment, on each and every continent and island of the earth, there are hundreds of thousands of creatures; plants, animals, birds, insects, bacteria, fungi, amoebae, protozoa, and other microbes that have evolved together over millenia, even millions of years. During this long time they have established complex relationships with each other synchronized to the various rhythms of seasonal climactic changes, yearly species migrations, and a number of other variable factors unique to their own particular biomes. Some animals are predators. Some are prey. Most are both. Individually, and as species, they are all playing the game of survival, doing their best to stay alive and healthy, one day at a time. Collectively, they make up the vast diversity of life on earth. The more varied and numerous the forms of life, the more stable and sustainable the ecosystems inhabited by them.
This bumblebee appeared as if it were resting, sleeping, or perhaps intoxicated into a stupor by the fragrance of this oregano flower, just prior to the taking of this photo.
All photos are copyrighted and may only be used with permission.
This common Chokeberry, Aronia melanocarpa, a shrub native to North America, attracts and feeds a wide variety of insects, which in turn pollinate its flowers. Once pollinated, the flowers become a delicious berry fed upon by other wildlife.
Everything is interconnected and interdependant...
When the ice sheets from the last glaciation period finally receded from North America into the arctic about twelve thousand years ago, this was a vastly different place than it was before this most recent ice age. Where there had once flourished lush vegetation and animal life, there was now bare bedrock, boulders, gravel, and assorted alluvial debris. Entire habitats and communities of plants and animals as far south as Virginia had been scoured away. No longer did foxes prey upon rabbits here. No longer did hawks swoop down upon smaller birds or squirrels. No longer did mountain lions pounce upon deer. The natural world that was here before the glaciers was gone. The ecosystem had been simplified, stripped of its diversity by the unstoppable crushing, grinding power of billions and trillions of tons of ice moving slowly southward over the land. Even the earthworms were gone.
Then the worldwide climate began to warm again and from south to north the glaciers slowly melted. From a small valley in the a mountain range we call the Great Smokies today, far enough south that it escaped the ravages of the destructive ice, plants and animals that had survived there began moving northward again.
This northward migration progressed very slow. Before animals could return, growing plants were required for food, and before most plants could repopulate an area there first had to exist soil, but on bare rock it could take a thousand years for an inch of top soil to form and many inches would be needed.

Soil is an amazing substance. It is not just dirty sand. When examined under the microscope it can be observed that soil is actually a complex living community. Comprised primarily of mineral matter from underlying bedrock, organic material called humus, detritus, air, water, and billions of living organisms, natural soils sustain all terrestrial life on earth. Soils also contain some surprising additional components. Volcanic dust, blasted high in the atmosphere during eruptions, circles the globe, settling out slowly upon soils worldwide adding trace mineral nutrients required by plants. Great sandstorms in the Middle East and Eurasian steppes also lift mineral dust and organic particulates into the upper atmosphere redistributing these materials worldwide, aiding soil fertility.
What is soil and why is it so important?
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