Tree advice from Arthur Lee Jacobson, author of “Trees of Seattle”

In the second edition of his book “Trees of Seattle,” Arthur Lee Jacobson points out that Seattle has only 33 species of native trees, but more 1,400 different kinds of trees are planted here, more than in any other city. “This,” he says, “is analogous to how few people in Seattle were born here compared to how many moved here from elsewhere.”

Born here or not, there are lots of opportunities for everyone to steward trees. While advice on taking care of trees might seem to apply only to property owners, Eastlake has a long tradition of neighbors just taking it on themselves to remove trash and invasives, to prune and garden our parks and public green spaces. Some trees belong to all of us.

There are also volunteer opportunities for aiding our urban forests on the city of Seattle website: https://www.seattle.gov/trees/get-involved.

In planning the ECC tree walk, which is taking place this Saturday, Oct. 23, I had a fun conversation with Jacobson about trees. Here is a summary of his advice:

Combat global warming, create natural cooling

Yes, plant trees! Planting trees is one good way to mitigate global warming. Plant a deciduous tree, says Jacobson, in the southwest corner of your lot if you can. It will provide shade in the summer to cool your dwelling and let light through in the winter.

If you can’t plant a tree, Jacobson who is a relatively recent apartment dweller has some alternate advice: Using R TECH Insulfoam that he found at the hardware store, sold like plywood in 4×8 sheets, he was able to cut it with a sharp knife to fit into his windows. A little duct tape around the edges didn’t hurt either. “These panels can be used to block summer heat/light,” he says, “and then used in winter night to retain heat.”

It’s never been easier to educate yourself

Once you discover a plant’s name, there’s a wealth of information that can be found about it on the internet. One cavate, he adds, a lot of gardening advice can have an East Coast bias.

Fall is the best time to plant trees – maybe, maybe not

Fall is promoted as the best time to plant trees, says Jacobson, because the winter months will water them. And newly planted trees need a lot of water.

But you can also plant trees in spring and summer when the selection for trees is at its peak.  And now is a good time to place your order for a particular tree if it’s not available for fall. And it may not be due to the pandemic and a rush on trees and plants.

You may even want to plant in spring and summer because the trees available by fall may not have been well tended by their nursery. Just remember to water.

Find the right tree

Many of the trees planted here thrive in our wet winters only to suffer in our dry summers. It doesn’t have to be that way. There are a lot of native and non-native trees that can do just fine here, says Jacobson. He has a list of 25 trees on his website that usually thrive: https://www.arthurleej.com/drytrees.html.

One size does not fit all

Be sure your space will accommodate the tree’s full-grown size.

Besides water, what can we do to nurture the trees we have?

“Mulch!” says Jacobson. That’s key. But what is mulch? (Check the internet!) It’s things like leaves, grass clippings, wood chips, or compost. Laying a thick layer on top of dirt helps to control weeds and conserve water.

Many trees are surrounded by grass, and the best thing to do after mowing is to leave the clippings on the grass, he adds. Too often people remove the clippings and keep removing them. “Always taking and taking, and never giving back.”

If decomposing clippings are too unsightly, there are mowers now that will dice clippings to a fine, short-lived dust over the lawn.

Finally, consider replacing suffering and thirsty trees with native and drought-tolerant ones.

Get Creative

Besides the 25 trees listed above, Jacobson also has a list of 20 trees that are hard to find but that he says he’d love to see more of and that usually do well here so merit planting: https://www.arthurleej.com/a-Trees%20of%20merit.html.

For more information, check out his website at https://www.arthurleej.com/index.html