Recent greenhouse research with Japanese knotweed (Fallopia japonica) and related species
This is F. baldschuanica, also known as Polygonum aubertii or "Silver Lace Vine".
The silver lace vine has set seed every summer in the University greenhouse, even in the month after it was first sent to me as a dried out root ball with bare stems. However, I have had no luck getting the seeds to germinate.
Mom (and Dad?) and Baby
F. japonica var. "Variegated", a horticultural variety available for sale in the U.S., which is male-fertile and can also produce seed.
Offspring of F. japonica var. "Variegated"
F. japonica var. "Crimson Beauty" (note the red pigment in the
vegetation and inflorescences), also available for sale in the U.S.
Crimson Beauty produces shorter, rounder fruits than wild F. japonica, and the fruits have a pink tinge to them.
Knotweed seedlings compete for light and space in the growth room at the UMB Greenhouse.
Offspring grown from seed to adulthood were a mixture of male and female plants. On the left is a female plant with developing fruit, and on the right is a male plant in flower.
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