Trees help clean the air we breathe, filter the water we drink, and provide habitat to over 80% of the world's terrestrial biodiversity.
Forests are being destroyed and degraded at alarming rates. Deforestation comes in many forms, including fires, clear-cutting for agriculture, ranching and development, unsustainable logging for timber, and degradation due to climate change.
Check with your city for their tree planting program. It's important that the tree be native to your area. Native plants require much less watering, fertilizer, and pesticides. In fact, they can prevent water run-off and improve air quality. They provide a habitat to support native birds and pollinators and wildlife. Sadly many city parks and recreation departments don't know this. Help educate them
One Tree Planted - https://onetreeplanted.org/
National Forests - https://www.nationalforests.org/get-involved/tree-planting-programs
Urban Tree Foundation - http://www.urbantree.org/
Plant a Billion Trees - The Nature Conservancy - https://www.nature.org/en-us/get-involved/how-to-help/plant-a-billion/
Endless Orchard project asks you to plant a fruit tree in your front yard and map it for others to see. https://endlessorchard.com/