AGRONOMY EXAM WITH UPDATED SOLUTIONS #5
True/false: a weed is any plant growing that is not wanted - correct answer True
True/false: the term weed is applied to unwanted plants in human-made settings -
correct answer True
Agriculture definition of weeds - correct answer Plants that cause economic loss to a
valuable crop, are harmful to humans and livestock, or are detrimental to wildlife
ecosystems
How many years can a weed stay in the soil? - correct answer 40 years
Noxious weed - correct answer the federal and state government's categorization of
weeds that are especially undesirable
Kudzu - correct answer a Japanese vine that is invasive to the Southeastern US
Canada thistle - correct answer a creeping plant that reproduces from vegetative buds
in its root system and from seeds
Itchgrass is native to where? - correct answer Old world tropics
What part of the US is saltcedar found in? - correct answer The American West
Hydrilla is found in and adversely affects what kinds of habitats? - correct answer
Freshwater habitats
What are four characteristics that classify weeds? - correct answer Invasiveness,
environments in which they grow, life cycles, taxonomy
True/false: invasive plants are nonnative plants that become established in natural plant
areas - correct answer True
True/false: invasive plants have the ability to reproduce rapidly and to spread by seed or
asexual means - correct answer True
True/false: a Chinese tallow tree is considered to be invasive - correct answer True
Bahia grass is an invasive species that was brought to America in ____ - correct answer
1751
Where do terrestrial weeds grow? - correct answer Land
Where do aquatic weeds grow? - correct answer Water
, In what ways do aquatic weeds cause problems? - correct answer They destroy wetland
ecosystems and clog irrigation canals
What are four types of annual weeds? - correct answer Morning glory, barnyard grass,
pigweed, cocklebur
How long can perennial weeds live for? - correct answer Three or more years
What region of the world is Johnson Grass native to? - correct answer Mediterranean
What year was Johnson Grass introduced to the US? - correct answer 1830
What type of weeds are the most difficult to grow? - correct answer Perrenial weeds
True/false: once established, perennial weeds are difficult to control except by
herbicides - correct answer True
What is the mission of Animal and Plant Health Inspection Service(APHIS)? - correct
answer to protect and promote US ag health and to regulate GMO use
What does USDA stand for? - correct answer United States Department of Agriculture
What does TDA stand for? - correct answer Texas Department of Agriculture
What is the primary method of weed prevention? - correct answer Herbicides
Advantages of herbicides - correct answer reduced cost, greater flexibility in timing,
effective in eliminating target species, no need for mechanical tillage, long term control
Disadvantages of herbicides - correct answer can kill non-target species, contamination,
can lead to herbicide-resistant species, human error in application
Widespread development of modern herbicides occurred after what year? - correct
answer 1945
How many herbicides are marketed in the US today? - correct answer 100+
What year were roundup-ready soybeans developed? - correct answer 1996
What year was roundup-ready corn developed? - correct answer 1998
What crops are currently roundup-ready? - correct answer Sorghum, canola, alfalfa,
cotton
True/false: glyphosate is a non-selective herbicide and is the most widely used
herbicide - correct answer True
True/false: a weed is any plant growing that is not wanted - correct answer True
True/false: the term weed is applied to unwanted plants in human-made settings -
correct answer True
Agriculture definition of weeds - correct answer Plants that cause economic loss to a
valuable crop, are harmful to humans and livestock, or are detrimental to wildlife
ecosystems
How many years can a weed stay in the soil? - correct answer 40 years
Noxious weed - correct answer the federal and state government's categorization of
weeds that are especially undesirable
Kudzu - correct answer a Japanese vine that is invasive to the Southeastern US
Canada thistle - correct answer a creeping plant that reproduces from vegetative buds
in its root system and from seeds
Itchgrass is native to where? - correct answer Old world tropics
What part of the US is saltcedar found in? - correct answer The American West
Hydrilla is found in and adversely affects what kinds of habitats? - correct answer
Freshwater habitats
What are four characteristics that classify weeds? - correct answer Invasiveness,
environments in which they grow, life cycles, taxonomy
True/false: invasive plants are nonnative plants that become established in natural plant
areas - correct answer True
True/false: invasive plants have the ability to reproduce rapidly and to spread by seed or
asexual means - correct answer True
True/false: a Chinese tallow tree is considered to be invasive - correct answer True
Bahia grass is an invasive species that was brought to America in ____ - correct answer
1751
Where do terrestrial weeds grow? - correct answer Land
Where do aquatic weeds grow? - correct answer Water
, In what ways do aquatic weeds cause problems? - correct answer They destroy wetland
ecosystems and clog irrigation canals
What are four types of annual weeds? - correct answer Morning glory, barnyard grass,
pigweed, cocklebur
How long can perennial weeds live for? - correct answer Three or more years
What region of the world is Johnson Grass native to? - correct answer Mediterranean
What year was Johnson Grass introduced to the US? - correct answer 1830
What type of weeds are the most difficult to grow? - correct answer Perrenial weeds
True/false: once established, perennial weeds are difficult to control except by
herbicides - correct answer True
What is the mission of Animal and Plant Health Inspection Service(APHIS)? - correct
answer to protect and promote US ag health and to regulate GMO use
What does USDA stand for? - correct answer United States Department of Agriculture
What does TDA stand for? - correct answer Texas Department of Agriculture
What is the primary method of weed prevention? - correct answer Herbicides
Advantages of herbicides - correct answer reduced cost, greater flexibility in timing,
effective in eliminating target species, no need for mechanical tillage, long term control
Disadvantages of herbicides - correct answer can kill non-target species, contamination,
can lead to herbicide-resistant species, human error in application
Widespread development of modern herbicides occurred after what year? - correct
answer 1945
How many herbicides are marketed in the US today? - correct answer 100+
What year were roundup-ready soybeans developed? - correct answer 1996
What year was roundup-ready corn developed? - correct answer 1998
What crops are currently roundup-ready? - correct answer Sorghum, canola, alfalfa,
cotton
True/false: glyphosate is a non-selective herbicide and is the most widely used
herbicide - correct answer True
