Even though silk never became a major commodity in North America, it indirectly made an impression on American gardening. The tree that was developed to most efficiently feed silkworms is now among the most popular of shade trees. The fruitless mulberry, Morus alba, wastes no resources producing fruit while providing only abundant foliage, which is the only sustenance for silkworms.

Young trees grow at a good rate to nearly thirty feet tall, and can eventually reach fifty feet. They are often pollarded (pruned severely back to the same burly ‘knuckles’ every winter), which causes them to regenerate stems at an alarming rate during summer. Shoots from mature pollarded knuckles have no problem reaching fifteen feet in all directions! Mulberries incidentally have the distinction of the fastest motion known to the plant kingdom, because they launch their pollen at more than half the speed of sound!

The serrate leaves are quite variable. Those of vigorous young shoots of pollarded trees are mostly about six inches long with rounded wide lobes, but can be nearly a foot long! They turn bright yellow and typically fall neatly from the tree within a limited time in autumn, facilitating raking. Leaves on slower growing stems of lightly pruned mature trees are mostly unlobed and less than six inches long. They begin to fall earlier in autumn and linger over a longer time, sometimes with slightly subdued autumn color.