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Arbor Day: celebrating the trees' value

Have you ever imagined what the world would be like without trees? If the urban forest is not well cared for, future generations won’t have to imagine cautions the International Society of Arboriculture (ISA). Planting and maintaining trees is vital to preserving the urban forests in communities around the world.

Arbor Day is a national holiday created to recognize the importance of trees. It is celebrated every year on the last Friday in April in United States and the 21st of November in Italy. The most common way people to celebrate Arbor Day is to get together in groups to plant trees.

The day was the brainchild of Julius Sterling Morton, a Nebraskan journalist who later became the U.S. Agriculture Secretary under President Grover Cleveland. Morton was an enthusiastic promoter of tree planting, had long championed the idea of a day dedicated to planting trees.

Arbor Day was first celebrated in Nebraska on April 10, 1874, following a proclamation by Gov. Robert W. Furnas. In less than a decade, the idea for the holiday caught on in other sates until, by 1882, its observance had become a national event. Nebraska made Arbor Day a legal holiday in 1885, moving it to April 22, Morton’s birthday. An estimated one million trees were planted during the first Arbor Day.

Many other countries around the world set aside one day each year to celebrate trees, though not all of them take place on the same day as Arbor Day. One of the oldest is Tu Bishvat, a minor Jewish holiday that usually falls in late January or early February. In ancient times, the people of Israel used this day to plant trees and celebrate their gifts by eating dried fruit and nuts, including figs, dates, raisins, carob, and almonds. Many American Jews still observe this day.

Trees planted today will offer benefits for years to come including altering the environment in which we live. Improving air quality, moderating climate, and conserving water are prime examples of the paybacks the urban forest can provide.

Improvement of air quality is obtained through the filtering process of the leaves.

  • Filtering removes dust and other particulates from the air
  • Absorption of air pollutants such as carbon dioxide, carbon monoxide, and sulfur dioxide
  • Renews the air supply by producing oxygen


Climate Control is obtained by moderating the effects of sun, wind, and rain.

  • Glare and Reflection Control
  • Wind Break, Deflection, and Filtration
  • Protection from downward fall of rain, sleet, and hail
  • Cost reduction due to shade and shelter, reducing yearly heating and cooling cost.

Water conservation occurs due to the interception of water by trees.

  • Reduction of storm run-off, erosion, and the possibility of flooding
  • Improvement of water quality through purification by slowing and filtering rain water

According to Jim Skiera, ISA Executive Director, “We often think of planting trees in a rural setting, overlooking that more than 80% of the population live in our cities, where additional trees can provide the greatest benefit.” As communities grow, individuals need to consider what contributions they can make to improve the urbanized environment we live in.

Skiera advises, “With a small investment individual homeowners can play a role in improving the effects of urbanization by planting and maintaining trees.”  It is never too late to reap the environmental benefits that trees can provide. To paraphrase a Chinese proverb- the best time to plant a tree was 25 years ago, the next best time is today. 

For more facts on the environmental benefits of trees visit

Annex: the official document sent by ISA exclusively for aboutplants 

Writes the president of the ISA. On November 21, a feast of great value, as happens in the U.S. for over a century