Bushkiller was evaluated under inter- and intraspecific competition. In experiment 1, bushkiller, trumpetcreeper, and wild grape were greenhouse-grown alone and in two or three species mixtures in pots. Of the three species, bushkiller grew the tallest and had the greatest final biomass when grown alone. When all three species were grown together, bushkiller grew over twice the height of trumpetcreeper, over three times the height of wild grape, and over four times the biomass of either competing species. Plots of height over time showed that competition did not affect bushkiller or wild grape growth rate, but trumpetcreeper growth was reduced when grown with bushkiller. In experiment 2, bushkiller was grown in cultures of one, two, and three plants per pot to determine intraspecific competition effects on growth. Final height of bushkiller was not affected by intraspecific competition; however, bushkiller biomass decreased with increasing competition.
Nomenclature: Bushkiller, Cayratia japonica (Thunb.) Gagnep.