Knotweed attracts honey bees in fall. Bamboo honey it is called for those apiaries foraging it. It also supports a fly parasite of Japanese beetle and a wasp parasite of Japanese beetle. One fly emerges from the adult beetle. This coincides with the mating in the fall and the blooming of the plant. Honey bees attend it heavier than any fall native plants like golden rod which is a good plant for preparing the bees to winter over. It produces a significant amount of resveratrol a polyphenol protective molecule found in smaller quantities in grapes. Both plants aid human health. A heavy ground cloth will kill it, successive cutting will also kill it and ammonium sulfamate has been used as an effective chemical control. See wikipedia it on ammonium sulfamate, it covers the herbicidal properties in more detail. The spring shoots are edible and have been consumed in its native lands for thousands of years by indigenous people.
