How air rots a fruit


Trees play an important role in the regional customs the human. In the tree symbolism, the majestic oak stands as the "queen of the forest" for values ​​such as strength, freedom, honor, strength and immortality. The oak is a typical court tree under which judgments have been pronounced for many centuries. The properties attributed to the oak should have a positive effect on the fairness of the judgments.


Typical of the oak is its fruit, the acorn. Due to its high proportion of starch, fat and protein, it is very nutritious, but it is inedible raw for humans due to the bitter substances. On the other hand, can you explain the saying "The best hams grow on oaks"? This refers to the centuries-old fattening of wild boars that were fed the rich acorns. And so it was said that pigs fattened with acorns provide tasty meat and firm bacon.


Speaking of strength: oak is known for its high strength and is therefore often used for furniture production and parquet floors. But not only that! Did you know that seasoned oak wood, i.e. oak wood that has been left lying around for a long time, is so hard that not even a nail can be hammered into it? Oak wood does not rot as long as it is kept permanently under water without oxygen. In the Dutch city of Amsterdam, for example, both the train station and the houses along the historic canals are built entirely on oak piles.

Air conditioning of nature

  • Trees can transport water from the ground to a height of over 100 meters - a top physical achievement! Most of it evaporates again through their leaves and thus contributes to the humidity.
  • They consume more carbon dioxide (C02) than they produce oxygen (02). How much a tree can contribute to fresh air depends primarily on the diameter of its crown and how many leaves it has.
  • A 150-year-old beech tree, for example, produces around 11,000 liters of oxygen every day, which is roughly the daily requirement of 26 people. It evaporates up to 500 liters of water a day through its leaves - that's the content of around four bathtubs.

In addition, trees have other good properties! You...

  • filter dust and other pathogens such as bacteria and harmful fungi out of the air
  • donate shade
  • reduce the wind speed
  • reduce the noise
  • produce wood
  • deliver fruit
  • create habitat and are a source of food for numerous animal species
  • improve the soil with humus through leaf fall and dead wood
  • beautify our cities

    1. How many oak species are there worldwide?

    2. How many kilograms of acorns does an oak tree produce per year?

    3. How old can oaks get?

    4. Many of you have an oak leaf with you every day. How can that be?

  • 1. There are around 600 species of oak known. Oaks are one of the most species-rich genera among the deciduous trees.

    2. Around 150 kilograms. That's about the weight of two men.

    3. You will be over 1,000 years old. That fills the average lifetime of 13 people in Germany. On Johns Island in South Carolina (USA) there is an oak called Angel Oak, which is said to be up to 1,500 years old.

    4. The reverse of the German 1, 2 and 5 euro cent coins shows an oak leaf. Take a look! It is a symbol with history: in the German Coin Treaty of 1837, Germany was made a unified economic area. To emphasize this new unity and strength of the German states, the oak leaf was chosen as a symbol for the coins. Nothing has changed to this day!

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