From what I can see, there looks to be both opposite and alternate leaves. The alternate leaves are not far from being opposite.
I would swear that some leaves are opposite, check this photo from MOBOT ..
http://www.missouribotanicalga...
Tree of heaven resembles the sumacs and hickories, but is easily distinguished by the glandular, notched base on each leaflet
http://www.invasive.org/weedcd...
You can see on the next link howclose to being opposite the leaves are ..
http://www.namethatplant.net/g...
I cropped part of Sharon's pic to show the leaf notches which look glandular, and alternate leaves.