Achieving this goal does not come without challenges. Large tree planting initiatives are faced with many problems, including losses from climate change, tree pests and invasive species, and urban development.

Michelle Kondo

The major ways that nature or green space can improve health include improved social contact and cohesion -- how we relate to each other other, it can also improve stress levels and increase opportunity for physical activities.

One thing we do know : In areas where neighbors are coming together to do gardening, there is less gun violence -- as opposed to hiring contractors to come in and do the work. There's more social cohesion, and people activate [ public ] spaces, there's also the broken windows theory -- when Michelle Kondo see a space that's uncared for.