You look down at the little seedling sticking up out of the dirt. It’s hard to imagine that one day, this small tuft of green might grow to be a tree that towers over you.
But where will this tree get all of the materials it needs to grow? From the soil? From the water? What about from the air? Like humans, plants are made of mostly of water.
But, when you take away the water, where does the rest of the mass of a plant come from? If you removed the water from our bodies, you would find that carbon makes up most of the rest of our mass, or weight.
The same is true for plants. Humans and animals get carbon from the food they eat, which is often plants. So where do you think the plants get carbon?
They get it from the air. The air around you seems empty, but it’s not. Air is made of tiny bits called molecules.
When you look closer at the molecules in our air you will find that it is mostly nitrogen, oxygen, and carbon dioxide.
Plants actually absorb this carbon dioxide from the air through small openings in their leaves or other tissues. These openings are called stomata.
Once inside a plant, the carbon dioxide is broken down, and some of the carbon ends up in the chloroplasts. Chloroplasts are special cell parts that hold chlorophyll, the molecules that make most plants green.
Chloroplasts are also where photosynthesis takes place which is how plants convert sunlight energy into food they can use.
Carbon, water, and energy are used in this process, to make glucose which is a type of sugar. Glucose molecules can then combine to form long chains called cellulose, which are used to build plant structures,
like cell walls. So the carbon from the air, along with water and energy from the sun, help to make these structures. As cells grow, they divide, and make new cells.
These new cells are how plants get bigger. The most amazing part of this process is changing air into plant material.
This sort of “magic trick” transforms something which seems weightless and empty into material that has weight and that you can see.
From a tiny seedling to a tall tree making seeds of its own From a tiny seedling to a tall tree making seeds of its own plants grow by pulling carbon out of the air.
plants grow by pulling carbon out of the air. So in the end, plants really are made out of thin air.
Reports of climate change, global warming and greenhouse gas emissions have been all over the news lately. What does this have to do with agriculture? After many decades of being pointed to as a source of environmental issues, field crop agriculture is being looked to as one of the solutions to global climate change. The basis for this environmental remediation affect is corn’s and other crops’ tremendous potential to remove carbon dioxide (CO2), a major greenhouse gas, from the atmosphere. In fact, Michigan growers can now receive payment for storing carbon in the soil via private sector carbon credit trading managed through the Chicago Climate Exchange.
How much carbon dioxide does an acre of Michigan corn absorb in a growing season? That is a question that is often asked, and the answer may surprise many people.
Our calculations show that number to be in excess of 36,000 lbs. of carbon dioxide per acre! Of course, much of that carbon is eventually returned to the atmosphere as the
corn crop residue decomposes or the grain is consumed as feed or burned as biofuel, but farmers can maintain a significant amount of carbon in the soil with proper management
including implementing reduced or no-till cropping systems. Currently, the Climate Exchange bases Michigan carbon payments on approximately 0.4 to 0.6 tons of carbon dioxide
equivalent per acre per year depending upon your location and the specific management practices implemented. The price paid per unit of carbon is based annually upon current market prices.
When used as a renewable fuel source such as ethanol, corn also displaces petroleum-based gasoline, a significant contributor of carbon dioxide to the atmosphere.
Each gallon of gasoline burned emits 19.4 lb. of carbon dioxide (5.3 lb of C) to the atmosphere. In fact, the USEPA estimates that the average car in the United States emits
approximately 6 tons of carbon dioxide to the atmosphere annually. Current estimates put U.S. gasoline consumption at about 140 million gallons per year and climbing. The
carbon emitted from gasoline is new additional carbon in the atmosphere – carbon that was formerly buried deep under the earth’s surface. Conversely, burning renewable fuels
such as corn ethanol has the potential to be carbon neutral since emissions would be essentially recycled carbon.
In what is perhaps his best-known experiment, Jean Baptist van Helmont placed a 5-pound willow in an earthen
pot containing 200 pounds of dried soil, and over a five-year period he added nothing to the pot but rainwater or distilled water. After five
years, he found that the tree weighed 169 pounds, while the soil had lost only 2 ounces. He concluded that “164 pounds of wood, bark and roots
arose out of water only,” and he had not even included the weight of the leaves that fell off every autumn. This tree was grown entirely without
How can trees be so tall. And do they grow from from nutrients out the air or ground.
In what is perhaps his best-known experiment, Jean Baptist van Helmont placed a 5-pound willow in an earthen pot containing 200
pounds of dried soil, and over a five-year period he added nothing to the pot but rainwater or distilled water. After five years, he found that the tree weighed
169 pounds, while the soil had lost only 2 ounces. He concluded that “164 pounds of wood, bark and roots arose out of water only,” and he had not even included
the weight of the leaves that fell off every autumn. This tree was grown entirely without any fertilizer!
Why is it that we dont understand as much as we think we understand. 7 years old do better than PhDs.
Richard Feymann on Tree and Plant Growth Explains Tree and Plant Growth