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Unfortunately where I am Google is blocked so my searching for this tree is somewhat crippled.
Found by a staircase to an overpass in the city of Urumqi, with temperatures ranging from -/+ 34 deg Celcius. Right now it's closer to the latter.
And seed pods opened
That looks like a northern catalpa, or catalpa speciosa (but probably another kind of catalpa; I'm just only intimately familiar with northern catalpas). Whatever it is, it's a catalpa.
We've had a few of those in our yard (and lots of seedlings as weeds). I grew up with a neighbor who had a couple large ones in their yard. Here's a picture of one that I just took moments ago:
Since you're in China, it might be a Chinese catalpa (Catalpa ovata), which is a Chinese native, though. It looks more like ours to me, though, or maybe a southern catalpa (Catalpa bignonioides). The pictures I saw of the pods of the Chinese catalpa had very thin pods.
It could also possibly be the Manchurian catalpa (Catalpa bungei), which is also from China. This kind has pink flowers, and the others all have predominantly white flowers, I believe. I'm not sure if the Manchurian catalpa can have white flowers, too, or not, but there may be different breeds.
The northern catalpa can survive as low as USDA hardiness zone 4. The Chinese can handle 3 or 4, depending on who you ask. The Manchurian and Southern can handle as low as zone 5. Northern catalpas are great with summer heat and drought in a BSk climate, but they come from a humid climate (something like Cfa). I'm not sure about the others.
The northern catalpa gets 40-60' high with a 20-40' spread (rather large). The southern gets 30-40' high. The Chinese gets 20-30' tall. I believe the Manchurian gets various sizes (I think some are dwarfs and some get bigger).
The seeds in your pictures have more prominent non-papery portions than those of our northern catalpa trees. So, I'm guessing you have a different species.
The only species I know about with reported edible parts is the Chinese catalpa (Catalpa ovata). It is said to have edible flowers and seed pods. I believe at least one species has toxic roots.
The main pest I've heard about for catalpas (northern and southern catalpas) is the catalpa sphinx (Ceratomia catalpae; a kind of hawk moth). The caterpillars eat the leaves, although it's not supposed to harm the tree. I don't see those on catalpas in my area, though. Not even birds enter the northern catalpa trees in my area (usually; if there's a bird feeder in one, they will—I think I've seen a hummingbird on the very top a few times). I think I've seen black, winged aphids on the leaves before (and flying around the trees).
Northern catalpa trees we've cut down tend to try to grow back a lot. The wood seems pretty light, and seems to burn quickly.
Looks like Catalpa Speciosa to me.
