Answers to Resistant Weed Quiz
The answers to the Resistant Weed Quiz are in bold. How did you do?
- What is the definition of herbicide resistance?
- The incremental tolerance of a weed population to a herbicide with each generation, eventually leading to resistance.
- The failure of a herbicide to kill a plant.
- The inherited ability of a plant to survive and reproduce following exposure to a dose of herbicide normally lethal to the wild type.
- Research shows (Bill Johnson, Purdue University) that the prevalence of giant ragweed is highly correlated to the management and use of glyphosate.
- True
- False
- Common Lambsquarters has been officially confirmed resistant to glyphosate in Wisconsin.
- True
- False
- Which state is home to tri-resistant waterhemp (ALS, PS II, PPO)?
- Illinois
- Indiana
- Iowa
- Minnesota
- According to speculation based on university research which glyphosate-resistant weed could be the biggest threat to the cotton industry since the boll weevil?
- Johnsongrass
- Marestail (horseweed)
- Velvetleaf
- Palmer pigweed
- Which weed has become more prevalent in recent years due to the widespread use of glyphosate-tolerant corn?
- Waterhemp
- Volunteer corn
- Giant ragweed
- When is the ideal time to apply glyphosate?
- When weeds are large, since glyphosate can control large weeds.
- Doesn't matter what size the weeds are, glyphosate should be applied in early June.
- When weeds are no larger than 4 to 6 inches tall.
- Name this glyphosate-resistant weed
Is it:
- Marestail (horseweed)
- Palmer pigweed
- Waterhemp
- Common lambsquarters
- Which of the following are good management practices to use on your fields?
- Scouting
- Alternate herbicide modes of action
- Using a pre-emergence residual herbicide
- Apply glyphosate to the proper weed size
- All of the above.
- Researchers estimate that about which percent of the weed population is resistant by the time growers recognize it in the field?
- 10 percent
- 20 percent
- 30 percent
- 50 percent