Alicia,
Even though you are almost as far to the East side of the continent as you can get, might I suggest one or two Left Coast organizations for the mix? Sempervirens is similar to the Nature Conservancy, but centers its efforts on the West Coast. They purchase land that can be annexed into state and national parks. As the name implies, their traditional emphasis has been stands of Sequoia sempervirens, the coastal redwoods that are found from Central California to southern Oregon. Barb and I give something to them each year. My Scout Council sold half of one of our camp properties in the Santa Cruz Mountains to them, that forms a bridge joining two state redwoods parks, which now form an almost continuous chain along the SF Peninsula (still a few gaps). There is a trail system that goes through these parks.

The Pacific Crest Trail Association is similar to the AT association, but for the PCT. The PCT is longer than the AT, stretching from the Mexican Border to the Canadian Border.

Of course you may suggest some, Bill! Thanks for doing so.

We aim to support a mix of local, regional, national and even international organizations. I like to balance it out and have a range of groups. For example,some groups, like LNT and the American Hiking Society, seem obvious for us to support, but The Trust for Public Land may not be quite so obvious. However, they do quite a bit of work with parks in urban settings to provide natural places accessible to everyone, something I think is necessary if we want people to become engaged with the outdoors.

So I review the list each year. It can be tough, because there are lots of places doing good works.

Since we support the ATC, I'll look into supporting the PTC too.

Sempervirens sounds nice too. I'd like to consider ways to choose a different charity or two each year that our members like.

More than a year ago we did a contest and entered everyone who wrote a review in a certain time frame for the chance to have a donation sent to the charity of their choice.

Maybe we should do something like that for Earth Day.

Other thoughts?