Arbor Day is a day dedicated to planting and caring for trees. It is observed on different dates in different countries, the last Friday of April in the United States, early June in Australia, and other dates elsewhere. The US Arbor Day Foundation is the world’s largest tree-planting organisation, with 500 million trees planted since 1972. This page covers what Arbor Day is, when it is observed, how it differs from Earth Day, and how to celebrate it, including how ForestNation’s verified Tanzania reforestation relates to the Arbor Day mission.
Key Takeaways
- Arbor Day is a day dedicated to planting trees. In the United States, it is observed on the last Friday of April, in 2026, that is April 24.
- Arbor Day was founded in Nebraska in 1872 by J. Sterling Morton. On the first Arbor Day, more than one million trees were planted in Nebraska.
- The Arbor Day Foundation is the primary US organiser. ForestNation plants trees in Tanzania, a complementary approach for companies wanting verified, field-measured reforestation for ESG reporting.
- For planting trees as a gift or for corporate programmes: forestnation.com/corporate-gift-a-forest.
When Is Arbor Day 2026?
In the United States, Arbor Day 2026 is Friday April 25, the last Friday of April. Individual US states set their own Arbor Day dates based on optimal planting conditions in their climate: Texas observes Arbor Day in January, Hawaii in November, Alaska in May.
Internationally: Canada observes Arbor Day on the third Friday of April. Australia’s National Tree Day is the first Sunday of August. The UK’s National Tree Week runs the last week of November. Many countries have their own equivalent, the concept of a dedicated tree planting day has spread to over 50 countries.
Arbor Day History
Arbor Day was conceived by J. Sterling Morton, a newspaper editor and later US Secretary of Agriculture, who moved to the Nebraska Territory in 1854. The Nebraska Territory had almost no trees, it was open prairie, and Morton observed that trees were essential for windbreaks, fuel, building materials, and the wellbeing of the landscape.
Morton proposed a state holiday for tree planting to the Nebraska State Board of Agriculture in 1872. The board set April 10 as the date. On that first Arbor Day, an estimated one million trees were planted in Nebraska. The day was so successful that Nebraska declared Arbor Day a legal holiday in 1885, setting the date on April 22, Morton’s birthday. Other US states followed.
The Arbor Day Foundation was established in 1972 to mark the 100th anniversary of the original event. It has since become the world’s largest tree-planting membership organisation, distributing trees and operating reforestation programmes globally.
Arbor Day vs Earth Day, What Is the Difference?
- Arbor Day: Specifically focused on trees, planting, caring for, and celebrating trees. Founded 1872. US date: last Friday in April. The original environmental holiday.
- Earth Day: Broader environmental focus, climate change, pollution, biodiversity, sustainability. Founded 1970. Date: April 22 globally. More political and campaign-oriented than Arbor Day.
- The overlap: Both celebrate the natural environment and promote action. In years where they fall close together (as in 2026, with Earth Day April 22 and Arbor Day April 25), the two days create a natural “tree planting week” for companies and schools.
How to Celebrate Arbor Day
Plant a tree. The most direct Arbor Day celebration. The Arbor Day Foundation offers native tree seedlings for members. ForestNation plants trees in verified Tanzania sites, field-monitored for survival and CO2 sequestration, particularly relevant for companies wanting ESG-reportable reforestation. For planting a tree in someone’s name: plant a tree as a gift.
Learn about trees in your local area. Identify native species in your neighbourhood. Understand which trees are planted where and why. Visit a native tree nursery or arboretum.
Volunteer for a local tree planting. Most local councils and conservation organisations run tree planting events around Arbor Day. Physical planting in your own community is deeply connecting.
Support verified reforestation. ForestNation’s Tanzania reforestation programme plants native and naturalistic species at five verified sites, monitored for survival, growth rate, and CO2 sequestration. Field data published at forestnation.com/impact-methodology.
Teach children about trees. Arbor Day is a natural moment for school activities, seed planting, tree identification, learning about the role of trees in carbon cycles, biodiversity, and water systems. See reforestation activities for students.
Arbor Day for Companies
Arbor Day falls at the end of Earth Week in 2026 (April 25, one day after Earth Day April 22), making it a natural extension of corporate sustainability campaigns. Companies can use Arbor Day to plant trees for employees and clients through ForestNation, personalised Gift Stories with field-measured environmental data, globally delivered by email, ESG-reportable. For corporate Arbor Day campaigns: forestnation.com/corporate-gift-a-forest.
Trees for Arbor Day, What to Plant
Native species are the highest-value choice for Arbor Day planting. Native trees support the insects, birds, and mammals that evolved alongside them. Non-native ornamentals often provide little wildlife value despite being beautiful.
- UK native trees: Oak (Quercus robur), ash (Fraxinus excelsior, though now threatened by ash dieback), hazel (Corylus avellana), silver birch (Betula pendula), hawthorn (Crataegus monogyna).
- US native trees (Eastern): Red maple, tulip poplar, river birch, black walnut, Eastern redbud.
- US native trees (Western): California oak, ponderosa pine, big-leaf maple, Pacific dogwood.
- Tanzania (ForestNation sites): Species selection at each of the five sites is determined by local ecology, including Acacia, Terminalia, and other native and naturalistic species appropriate for the specific degraded land being restored.
The Arbor Day Foundation
The Arbor Day Foundation is a nonprofit membership organisation founded in 1972. It operates tree-planting programmes in forests across the United States and internationally, distributes trees to members, runs the Rainforest Rescue programme, and operates the Tree City USA programme recognising communities that maintain urban forests. arborday.org.
ForestNation is a complementary organisation focused on verifiable tropical reforestation in Tanzania, with published field data suitable for corporate ESG reporting. The two organisations serve different needs: the Arbor Day Foundation focuses on membership and local/national planting, ForestNation focuses on corporate programmes with field-measured impact data.
Research and References
- Arbor Day Foundation: arborday.org, history, tree distribution, conservation programmes.
- Nebraska State Historical Society: J. Sterling Morton and the history of the first Arbor Day, 1872.
- ForestNation: verified Tanzania reforestation, field-measured CO2 data. forestnation.com/impact-methodology
Frequently Asked Questions
When is Arbor Day 2026?
In the United States, Arbor Day 2026 is Friday April 25, the last Friday of April. Individual states set their own dates based on local climate. Canada observes the third Friday of April. Australia’s National Tree Day is the first Sunday of August.
What is Arbor Day?
Arbor Day is a day dedicated to planting and caring for trees. It was founded in Nebraska in 1872 by J. Sterling Morton. On the first Arbor Day, more than one million trees were planted. The Arbor Day Foundation now distributes trees and runs reforestation programmes globally, having planted over 500 million trees since 1972.
How is Arbor Day different from Earth Day?
Arbor Day (founded 1872, last Friday of April) is specifically focused on trees. Earth Day (founded 1970, April 22 globally) has a broader environmental focus including climate change, pollution, and biodiversity. Arbor Day is the older holiday, Earth Day the larger one. In 2026 they fall three days apart, creating a natural “tree week.”
What trees should I plant for Arbor Day?
Native species are the highest-value choice, they support the local insects, birds, and mammals that evolved alongside them. In the UK: oak, silver birch, hazel, hawthorn. In the US: varies by region, but red maple, tulip poplar, and Eastern redbud are widely appropriate. The Arbor Day Foundation distributes native tree seedlings to members based on your zip code.
