Sep 11, 2010

early adopters

If you are trying to learn tree identification, certain times of year are better than others. Right now is the time to learn black gum, sourwood, sumac and tuliptree. These trees get a head start on fall, turning colors while the rest of the trees remain green.

Tulips are turning yellow, the others red. Sumac tends toward fiery tones like you might see in a sunset. It also has compound leaves, and if it has produced fruit, the red, conical berry clusters are distinctive. Sourwood takes on regal tones that approach purple.

Black gum has the purest reds. Gums start losing leaves as soon as its fruit ripens, possibly as a signal to birds to come eat. Migrating thrushes are especially fond of black gum fruits. Leaves begin to turn red in August, but it takes weeks for all the leaves to turn, so there are always a few bright red ones on any tree at any point during fall migration.

Right now, all these trees are recognizable at a glance, so it's a good time for roadside dendrology. As you drive around, you can get a sense for how abundant these species are, where they grow and what is distinct about their growth form. As other trees start to turn, new colors will appear and the roster of trees you have learned to identify will get a bit longer.


Gregory Harrison said...

Thanks for these tips. I've been trying to improve my knowledge of trees as I've been serving on my city's "urban forestry" committee. There is a park in nearby San Marino which is helpful because it has lots of trees, and most of the trees have signs which identify them. I know there are a few tuliptrees there, so it will be interesting to see how they are changing - although i suspect the timing of the leaves changing will be later here in southern california.

Rikki Hall said...

Don't use Southern Appalachian tree ID tips too literally on the California coast! There is not much overlap in species, much less timing.

Both places have good diversity of oaks, but virtually none are the same species. Your hills are steep, young and dry; ours are worn, wet and ancient. You've got marine influences; we have glacial remnants.

You also have more introduced trees, some from the eastern US, but also the Mediterranean, Australian or Asian coasts, where climate is similar. I'm not sure our tuliptree (Liriodendron tuliperfera) would do well in San Marino, but I'd be interested if that's the case! I wonder whether you could be talking about the park my grandfather took me to. I remember eucalyptus trees there.

One tree I know we have in common is sweetgum (Acer liquidamber), and it's a tree whose leaves start turning early. It's also a tree you grew up with in W. Mass. My grandparents lived on Wetherby Rd in San Marino and had a big one in the front yard. They had a Southern magnolia and a lime tree in the back, and I suspect all three trees were planted on a cleared lot when the house was built.

Despite all the differences between here and there, it's still a good strategy to pay attention to when trees flower and shed their leaves when you are learning. It's a great way to tell which ones are the same kind.

Jackie said...

I've found that buckeye trees begin turning very early, this year in particular.

Gregory Harrison said...

I intended to take your tips more generally. We do have plenty of non-natives here (although the recent focus is on planting "California natives"... but of course we love the palm trees too.

The Liquid Amber is very popular - although recently a topic of conversation because it is known for "SLD" - sudden limb drop. Some citizens don't like it because of the seed pods, but i discovered one variety that does not have those pods. Not sure how that works though...must have some other seed mechanism.

Lacy Park does have huge eucalyptus trees (I think from Australia?) as well as many oaks, various pines (Torrey Pine, Canary Island pine), deodar cedar and Blue Atlas cedar. And palm trees. I'm fond of the Gingko myself, and another tree I like is called "Smoke tree".