Growth and Development
Tall waterhemp is a summer annual that produces a large amount of very small seed. It is considered an r-strategist. Emergence can span several months and often occurs later in the season than other annual weeds, allowing the weed to evade typical weed control strategies such as herbicide application and tillage. One study observed 80% emergence not occurring until ten weeks after the initial emergence. Extreme temperatures have little effect on seed viability. Germination occurs typically after soil temperature alternation, as this is required to break seed dormancy. Waterhemp has been found to germinate in a wide range of soil and temperature conditions. It has been found to germinate 17 years after seed set
While tall waterhemp cannot self-pollinate, due to having separate male and female plants, it does not require any vectors for pollination This allows for wind pollination over large distances, generating a large amount of genetic diversity. Another factor contributing to genetic diversity is the large amount of seed produced. Tall waterhemp in competition with soybean has been reported to produce from between 300,000 to 5,000,000 seed per plant. Tall waterhemp also has a rapid growth rate, 50%-70% greater than other annual weeds.
Read more about this topic: Amaranthus Tuberculatus
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