Costa Rica’s newest arboretum (website here) is a combination of innovative conservation technology and cutting-edge botanical research. The Osa Arboretum protects more than 300 native, rare, endemic and threatened tree species in the Osa Peninsula, a Costa Rican biodiversity hotspot. It aims to be one of the largest arboretums in Central America, with a trail network that spans more than 625 acres across old growth, secondary, mangrove and coastal forests.

When I arrived years ago at the piece of land I now garden, I saw it as a blank canvas and set about madly planting things, imagining my efforts would bring every square foot to life. I did not understand then that the heavy lifting had already been done — and probably by some blue jay, or maybe a squirrel.

One in four hardwood trees in the eastern United States was once an American chestnut. But no one today can take a walk in these woods beneath the once towering chestnut trees because the species is functionally extinct. 

There is increasing interest in tree planting as a nature-based solution to climate change. Many countries around the world have made pledges to the Bonn Challenge to bring millions of hectares of degraded land under restoration. However, there is growing concern in the biodiversity conservation and ecological restoration community that there is too little attention paid to which species are planted and where.

The Guelph area has a surprising diversity of tree species, and the Arboretum at the University of Guelph has just the thing to help schoolchildren identify them.

The Arboretum is producing hundreds of “Native Tree Leaves” sheets for distribution to more than 3,000 local Grade 6 students, and is working with the Upper Grand District School Board and the Wellington Catholic District School Board on ways to incorporate the resource into everyday learning.

In an effort to receive advanced warning of destructive pests that could wreak havoc on native plantings, researchers from Europe, the United States and China are growing "sentinel trees" in strategic locations around the world.

Faced with deforestation, climate change, invasive pests, and new diseases, many trees are in trouble. Foresters and conservationists are scrambling to save them, but can’t protect every stand of woods. And prioritizing which places—and even which individual trees—warrant preservation has been a challenge. For example, “You want a lot of genetic diversity in a conservation area. … The higher the diversity, the more the chances that the population will survive,” says F. A. (Phil) Aravanopoulos, a forest geneticist at Aristotle University of Thessaloniki.

Societal Impact Statement

A Cultural Landscape Foundation report lists the Holden Arboretum in Kirtland among 10 U.S. landscapes threatened by climate change.

The Foundation recently released Landslide, its annual report on the topic. Sites range from the Cape Hatteras National Seashore to Death Valley Scotty Historic District.