We would like to plant a special evergreen tree that would be a large heirloom or heritage tree. We would like this to be the centerpiece of our back yard. We know the type of trees that typically fall into this category will be slow-growing, so we want to plant it soon so that it will be big enough for our grandchildren to climb in, swing from, play under, etc.
We would like a tree that is quite large and wide (possibly even wider than it is tall, around 40 feet tall x 40+ feet wide), with branches that start relatively low on the trunk, but do not go all the way to the ground (so you could both climb into it and have a picnic table under it).
I recommend visiting your local arboretum. If you are in the Seattle area, the Washington Park Arboretum is one place where you will find many examples of mature trees, some of which are coniferous evergreens, some of which are broadleaf evergreens. There are also many useful books to help you select the tree that best suits your needs. Since you are interested in evergreens, I particularly recommend Richard Bitner’s Conifers for Gardens: An Illustrated Encyclopedia (Timber Press, 2007) and Portland, Oregon author Sean Hogan’s Trees for All Seasons: Broadleaved Evergreens for Temperate Climates (Timber Press, 2008).
Here are websites that are useful in narrowing down tree lists once you have a few ideas in mind. (Note: Some of the sites have a zone option, i.e. where the trees grow best. Seattle is in USDA Zone 8b & Sunset Zone 5). In some cases, you can narrow down the selection even further, by selecting tree attributes (see the SelecTree site below).
Virginia Tech’s Department of Forest Biology and Environmental Conservation has a series of
Tree Identification Fact Sheets. This site is best for descriptions when you already have a species in mind.
Search the SelecTree database from CalPoly.
The best way to get a good list (with numerous options) is to click on Select Tree by Attribute.
A classic source is the USDA Forest Service internet version of Silvics of North America. It will not help with selection since you will need to know what species you want, but it will provide more information than you will ever need.