Sometimes it pains me to take walks. I was on my way home from the Imperial Bottle Shop and Tap Room, walking down SE 26th south of Powell Blvd when I came across these four Katsura trees planted in a 4′ wide parking strip, no curb parking with a painted bike lane right next to the curb. Katsura trees 24″ from the bike lane. How is that going to work? Trees grow. Branches extend and caliper up. Branches hit bicyclists and pedestrians in the face and people crash and or break branches. (Yes, I know these can be limbed up over time but we all know how often that doesn’t happen and what are these trees going to look like if all of the branches are cut off of the street side up to 14′ for traffic clearance. Trucks regularly use this street.) And then there’s the whole it’s just the wrong plant for the growing conditions thing. Katsuras grow in the mixed woodlands of Japan with moderate temps and summer rainfall. So that looks like 3 strikes out of 4 pitches. Landscape architects still love these…so do I, but planting them in positions with reflected heat with limited root runs through compacted mineral soils!!!! It’s 90 degrees today, their foliage is stressed even with their water bags filled around their bases. I have seen many more bad examples of Katsura use over the last 25 years than i’ve seen appropriate. If you’re going to plant them plant them in a woodland or along the edge where they will be protected from intense direct sun and make sure they have a long cool root run. This is so wrong. Now we’ll all have to watch these limp along getting by stressing until they die or become so damaged someone removes them.
Before you choose your street trees walk around with someone who knows trees now, late summer, and notice all of the trees that are showing stress, curled or cupped leaves with burned margins, or stunted leaves with short internodes, trees exhibiting ‘fall’ color in August or already dropping them, trees exhibiting twig and branch dieback along with poor structure. Parking strips aren’t called hellstrips for nothing. Growing conditions tend to be very difficult on them. If you are going to have to baby a tree to get it established here it is likely that years down the road, when you have moved or lost interest and the tree has crowded the available soil with its roots it will become more and more difficult to maintain such trees. Their vigor will start to decline and their structure will serve as a daily reminder that you or someone else made a poor choice. Choose a tree that will do well in the given conditions not one that should be okay or tolerate it.
Trees have a fixed capacity to adapt. If your conditions are near the tree’s limit it won’t take much to push it past them and compromise the tree’s health. Just because someone is willing to sell you a tree doesn’t mean it’s the best or even a good choice…and, just because a tree is on a list of street trees doesn’t mean they are good or even appropriate for your site. It’s not just about what will ‘fit’ beneath the power lines. Know something about the trees you choose. Where do they come from? What are their preferred conditions? Will they their branching habit fit the space? After you plant them be clear about followup care and do it, including structural pruning. This is a parking strip with legally defined spatial limits, defined so for safety reasons. Your trees shouldn’t become obstacles for pedestrians and road users.
The above opinion is just mine. Who knows maybe they’ll be okay in spite of the conditions. Trees are not like annuals that we regularly replace. It’s kind of like in physics, ‘a body at rest tends to stay at rest…, a body in motion…..’ The same goes for trees, especially in a City with so many legal protections for street trees.