From the appearance of the leaves
1. The roots of toona sinensis leaves are light green and the tip of the leaves are yellowish brown; while the roots of the leaves of Ailanthus altissima are dark green and the tips of the leaves are gray-green.
2. There are sparse serrations on the edges of toon leaves; while Ailanthus altissima leaves do not.
3. The number of leaves. Ailanthus altissima has odd-numbered leaves and Chinese toon has even-numbered leaves. That is to say, the number of leaves on each branch of toon is always even. For example, six pairs, seven pairs, eight pairs, etc. The number of leaves on each branch of Ailanthus altissima is singular. It is always out of several pairs, and one more piece grows at the upper end, forming six and a half, seven and half, eight and a half, etc.
From the smell
1. Take a leaf and rub it with your hands, and smell it. "Ailanthus", commonly known as Ailanthus altissima. It looks like toon but the smell is weird and unacceptable.
2. The trunk is different. The surface of the tree trunk of Ailanthus altissima is smooth and not cracked, while the trunk of Ailanthus altissima is often peeled off.
3. The fruits are different. Toona sinensis is a capsule and Ailanthus sinensis is a samara.