Growth and Reproduction
A plant growth experiment was performed in the experimental garden from October 2017 to October 2018 in Yining City (43°50′–44°09′N,80°04′–81°29′E), located in the Yili Valley. This locale has an average annual temperature of 10.5°C and an average annual precipitation of 280 mm. Three irrigation treatment gradients were established in the experimental garden: (1) no irrigation with 280 mm of annual precipitation; (2) 2800 m3/hm2 of irrigation during the growth period (equivalent to 560 mm of annual precipitation supplemented by 400 m3/hm2 of irrigation every month from April to October 2018), and (3) 5600 m3/hm2 of irrigation during growth period (equivalent to 840 mm of annual precipitation supplemented by 800 m3/hm2 of irrigation every month from April to October 2018). Each water treatment was tested with three plots, and eighteen plots were randomly arranged with 3 m × 3 m plots for each irrigation sample area. Plastic film was buried vertically to a depth of 40 cm in the soil around each irrigation plot to separate the water received in each plot. Each plot was uniformly sprinkled with 900 seeds of A. artemisiifolia or A. trifida .