Study Guide 2025 | Updated Quiz Questions with
Verified Solutions
Weed management Strategies - o mechanical - tillage, mowing, flooding.
o cultural - rotation, competition.
o Biological - bugs
o chemical - herbicides
Growth Regulator Herbicides - Selective, Translocate
Example: 2,4-D
Amino Acid Synthesis Inhibitors - non-selective, translocate
Example: Arsenal, Roundup
Lipid Inhibitor - Selective, translocate, interfere with new hand growth
Seedling Growth Inhibitors - prevent root or shoot development on seedling
Photosynthesis Inhibitors - Interfere with photosynthesis
Example: Spike
Cell Membrane Disruptors - Contact herbicides
Example: Gramoxone
Pigment Inhibitors - Interfere with photosynthesis
Herbicide Application in Annual Life Cycle - Seeding and vegetative
Herbicide Application in Biennial Life Cycle - Seeding and Rosette
Herbicide Application in Perennial Life Cycle - Seeding, bud, early flower, full flower, fall
regrowth
Herbicide Tolerance and Resistance - o Tolerance - when a plant has historically survived
a particular herbicide action
o Susceptibility - when a plant is killed by herbicide action
, o Resistance - when a plant has evolved mechanism to survive a particular herbicide action.
Minimizing Herbicide Resistance - o Tolerance - when a plant has historically survived a
particular herbicide action
o Susceptibility - when a plant is killed by herbicide action
o Resistance - when a plant has evolved mechanism to survive a particular herbicide action.
2,4-D - Selective, growth regulator, high volatility, high potential for drift, peas, grapes,
and tomatoes very sensitive, grain and corn are not sensitive
Soil Residual Herbicides - Last from several weeks to several years, LTR's (long-term
residual herbicides) kill most vegetation and leave soil nonproductive from one to several years
Nozzle types - Solid stream, fan, cone
Nozzle materials: Carbide and Ceramic - Most expensive, most resistant to abrasion and
corrosion
Nozzle materials: Stainless steel - good resistance to abraision and corrosion, moderately
priced
Nozzle Materials: Brass - resist corrosion but not abrasion
Nozzle materials: Aluminum - inexpensive, resist some corrosion, wear quickly
Nozzle materials: Plastic - Swell when exposed to organic solvents
Changing pressure with nozzle sprayers - increasing pressure does not give a proportional
increase in output, so adjust pressure for minor changes in spray delivery rate
Change in travel speed with sprayers - inversely proportional to speed of sprayer: 2x
sprayer ground speed reduces amount of spray by 1/2
Making large changes in sprayer applications - adjusting the size of the opening (nozzle
tip) to increase or restrict flow
Applying Granular herbicides - speed inversely proportional to amount of material- more
speed= less material/ size of opening. larger opening= more granules
Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) - Overseen by US EPA
Pesticide Registration - EPA registers the product and it's uses