I don't know a petal from a petiole. What's this tree?

July 24, 2012 7:54 PM

Can you help me identify this tree? I tried to key it out but ran into the limits of my tree vocabulary. It's in Burnet Woods in Cincinnati and you can view photos of the tree, the leaves (which are alternate and barely serrated), the bark, and the fruit.
posted by toodleydoodley to science & nature (15 answers total)

First glance, and thinking horses not zebras, puts me at black walnut
posted by rockindata at 7:59 PM on July 24, 2012 [3 favorites]

looks like some kind of chestnut/walnut tree.
posted by lester's sock puppet at 7:59 PM on July 24, 2012

Looks like black walnut to me as well.
posted by RogueTech at 8:03 PM on July 24, 2012 [1 favorite]

Smear some of the juice from the fruit on your hand. If it's still stained brown next week, it's definitely a black walnut :)
posted by circleofconfusion at 8:05 PM on July 24, 2012 [3 favorites]

I had one of those growing up in my back yard as a kid. Looks like a black walnut.
posted by munchingzombie at 8:08 PM on July 24, 2012

Black walnut - we had lots growing outside the building we lived in when I was in high school (Boston).
posted by rtha at 8:08 PM on July 24, 2012

Oh yeah! So, do black walnut trees propagate by suckering, or by germinating the seed? My dad's neighbor has a tree like this in his yard and it sends runners in every direction, that seem to grow into trees.
posted by toodleydoodley at 8:18 PM on July 24, 2012

no, your dad's neighbor has an ailanthus, aka tree of heaven, aka f-ing nuisance! they look like black walnut but grow very rapidly, reproduce by suckers AND seed and smell funny. different funny than black walnut. they are an invasive exotic. i spend half my summers pulling the stinky little sprouts. grrr.
posted by miss patrish at 8:22 PM on July 24, 2012 [3 favorites]

the black walnut is native, slow-growing, food source for squirrels (and people!) and after many years' growth are an excellent hardwood tree.
posted by miss patrish at 8:24 PM on July 24, 2012

Ok, I'm prepared to believe the tree in question is ailanthus, except the fruit is definitely a capsule, not a samara. Walnut trees don't sucker?
posted by toodleydoodley at 8:40 PM on July 24, 2012

um, the tree you are asking about in this post is black walnut. they do not sucker and produce nuts. which squirrels bury, thus propagating new trees. however, the tree your dad's neighbor has is an ailanthus, which does sucker, as well as reproducing by seed. two different trees. sorry to be confusing.
posted by miss patrish at 9:02 PM on July 24, 2012

Black walnuts sucker heavily under the right conditions.
posted by oneirodynia at 9:04 PM on July 24, 2012

wow, oneirodynia; i've lived in missouri (apparently the black walnut capital of the universe! who knew?) my entire life and have never known a black walnut to send out suckers to produce new trees. i mean, they'll send up sprouts from the stump, but i've never known them to send out underground runners. it looks like you're in california? maybe there's a different variety of walnut there?
posted by miss patrish at 9:24 PM on July 24, 2012

I think what happens here is that many of the eastern black walnuts that are around now (in California) were originally rootstocks. Though they aren't native, and there's not really a black walnut crop here, English walnuts used to be regularly grafted to black walnut. Even if they overgrow their scionwood they've never had a true leader, so maybe that's part of why they are more likely to root sucker as well. Maybe our summer dry climate also encourages more surface rooting, which can mean wounds to tree roots, and then suckers. The trees are uncommon, most of the ones I see are old and in poor shape. These days english walnuts are more likely to be grafted to Juglans hindsii, the California walnut.

So a tree under poor conditions, with a watering regime it doesn't like, and surface roots that have been injured can sucker, more likely in urban/suburban areas.

toodleydoodley, your neighbor's tree might also be Rhus ssp. Fruits are drupes, and they often sucker.
posted by oneirodynia at 7:11 PM on July 25, 2012

Oneirodynia, I think you're right about it being a black walnut suckering under stress. Cincinnati is in a drought-flood cycle and the city has lost hundreds of healthy trees in the last few years. Maybe my dad can get his neighbor to water his tree so it won't be quite so stressed. Thanks, all, for your help.
posted by toodleydoodley at 6:39 AM on July 26, 2012