Agronomy General Knowledge Flashcards
Which of the following represents a fixed cost in a row-crop operation?
a. Labor
b. Depreciation on equipment
c. Fuel
d. Fertilizer
Depreciation on equipment
___________ is a type of pre-harvest loss where stems break and plants fall to the ground
Lodging
Which of the following facts can be found on a seed tag?
a. Country of origin
b. Percent hard seed
c. Percent chaff
d. Weight of bag
Percent hard seed
If a producer wants a corn population of 23,500 seeds per acre, and the seed is 80% viable and 90% pure, how many seeds per acre do they need to plant?
a. 21,150
b. 47,000
c. 32,638
d. 18,800
32,638
In the disease triangle, the ____ is the sum of conditions favoring susceptibility.
Host
Which of the following grasses is a warm-season grass?
a. Big Bluestem
b. Timothy
c. Kentucky Bluegrass
d. Tall Fescue
Big Bluestem
Unheated air may be used to dry harvested grain that contains no more than ______ moisture
15%
Which of the following plants is not classified as a legume?
a. Alfalfa
b. Clover
c. Birdsfoot Trefoil
d. All of these are legumes
All of these are legumes
Which of the following processes can decrease soil bulk density?
a. Wheel traffic on wet soils
b. Adding organic matter
c. Removal of crop residues
d. Continuous tillage
Adding organic matter
In using a rye cover crop for soybeans, a 2021 study showed early-season weed emergence was suppressed by about _____ when cereal rye was terminated before stem elongation was complete and a residual herbicide was applied at soybean planting
97%
Which of the following are factor(s) used in federal grain grading?
a. Moisture content
b. Test weight per bushel
c. All of these are factors in federal grain grading
d. Color
Test weight per bushel
During which stage of growth do plant nutrient needs dramatically increase?
Vegetative growth
Which of the following is true about purple-stained soybeans?
a. Symptoms appear in R3 stage
b. Caused by fungus Cercospora kikuchii
c. Caused by wet conditions at pod fill followed by dry weather
d. All of these are true
Caused by fungus Cercospora kikuchii
______________ refers to the projected loss of a crop that is equivalent to the cost of the treatment.
Economic threshold
The _________________ has the mission to protect human health and to safeguard the natural environment upon which life depends. They enforce state and federal laws developed to protect the environment.
Environmental Protection Service
_____________ is the system of planning narrow seedbeds without disturbing the soil, using herbicides to control weeds.
No-till
Evapotranspiration (ET) rate is largely a function of __________.
Atmospheric demand
Which of the following is a symptom of soybean cyst nematode (SCN) damage?
a. Leaves wilt in the morning more than those of healthy plants
b. Occurs in small to large oval areas of a field
c. Roots will appear lighter in color
d. Roots will have more nitrogen fixing nodules
Occurs in small to large oval areas of a field
Which type of erosion is small channels formed by running water that are small enough for implements to pass over, and can be easily filled?
Rill
________ protect soil surface from running water, raindrops, and wind erosion by slowing water and wind velocity, allowing sedimentation.
Cover crops
Which of the following particles contributes most to the Cation Exchange Capacity (CEC) of a soil (by weight)?
a. Illite clay
b. Kaolinite clay
c. Soil organic matter
d. Vermiculite clay
Soil organic matter
_________ refers to the amount of chemical that is required to cause death in 50% of a test population of laboratory animals
LD 50
___________ refers to the release of a nutrient when an organic materials (e.g. soil organic matter) is decomposed by soil microorganisms.
Mineralization
Which of the following crops has the lowest annual water usage?
a. Corn
b. Grain Sorghum
c. Soybeans
d. Alfalfa
Grain Sorghum
Plant available P is generally highest over a pH range of ______
5.5 – 7.0
When using manure for fertilizer, which of the following statements is true?
a. Less decomposed manure contains less organic N
b. All animal manure has similar nutrient content
c. As manure loses water, Ammonium (NH4+) is converted to Ammonia (NH3) and lost to volatilization.
d. Inorganic compounds like Phosphorus become more soluble as precipitates form
As manure loses water, Ammonium (NH4+) is converted to Ammonia (NH3) and lost to volatilization.
_________ is the conversion of organic N to ammonium (NH4+) by microorganisms as they decompose organic materials
Ammonification/Mineralization
Pesticide absorption through the skin is known as ____________________ absorption.
Dermal
Plant pathogens who survive as mycelia, spores, and sclerotia in infected plants, debris, soil, and insects is known as ________.
Fungi
Which of the following is NOT a hazard or limitation for cropping?
a. High water table of less than 3.5 feet
b. Land slopes longer than 90 feet and/or in excess of 2% slope
c. Less than 12 inches of available water in the upper 60 inches of the profile
d. All of these are a hazard or limitation for cropping
Less than 12 inches of available water in the upper 60 inches of the profile
he moisture content of silage at harvest is generally greater than _______
50%
____________is owned and supervised by the original plant breeder (usually an agricultural experiment station). This seed requires labels or tags.
Foundation seed
Which of the following would be considered a cultural pest control system?
a. Applying an insecticide
b. Releasing a disease into an insect population
c. Crop rotation
d. Generically modified crops
Crop rotation
Which of the following practices is NOT a part of Integrated Pest Management (IPM)?
a. Pesticides
b. Biological controls
c. Cultural Controls
d. All of these can be components of IPM
All of these can be components of IPM
At what grain moisture level will corn ears begin to be well dented?
35%
Which of the following is NOT a strategy for renovating a forage stand?
a. Overgraze grass during early fall and winter to remove plant material
b. Broadcast legumes in winter so freezing and thawing will cover seed
c. Avoid using Nitrogen in fertilizer mix as N stimulates older grass
d. All of these are forage stand renovation practices
All of these are forage stand renovation practices
The optimum temperature for soybeans to germinate is _________.
68 F
What bacterium is necessary for soybean nitrogen fixation?
Rhizobium japonicum
_______________ are adventitious roots produced above ground, often for climbing.
Aerial Root
Which of the following is NOT a high moisture forage storage system
a. Bunker silo
b. Bags
c. Silo
d. All of these are high moisture forage systems
All of these are high moisture forage systems
At what stage should alfalfa be harvested for hay?
First flower
Which of the following is NOT a corn pest from emergence to knee-high?
a. Thrips
b. All of these are pests from emergence to knee high
c. Southern corn rootworm beetle
d. Billbugs
All of these are pests from emergence to knee high
Which crop is typically planted using the drill method?
Wheat
The husk on the front, ventricle side of the grass seed is known as the _______
Palea
What is a characteristic of using direct heat drying of grain?
Potential to overdry grain (reducing quality)
What is the minimum heat units DD-60s necessary for planting cotton?
0
Which of the following nutrients are not mineralized from soil organic matter?
a. All of these can be mineralized from soil organic matter
b. Phosphorus
c. Nitrogen
d. Sulfur
All of these can be mineralized from soil organic matter
When is forage nutrient value the highest? (PS 43)
Early growth
What new technology allows farmers to apply herbicides and other pesticides through the air?
UAV
Why is cotton not produced in the northern climates?
cotton requires long frost-free periods
Which of the following is a fiber crop?
a. rice
b. flax
c. barley
d. soybean
flax
Seedling emergence is hindered by ________.
surface crusting
What is the Carrying Capacity of a grazing system?
the stock rate that is economically and environmentally sustainable for a particular grazing unit through the grazing season
What is the appropriate stage for maturity for harvest for smooth bromegrass?
Seed heads emerged
An average soil contains ______ mineral matter, 5% organic matter, ____ water, and 25% air.
45% and 25%
Why would hay be ammoniated?
to improve quality by breaking down cell wall linkages
If a forage has cells with thin walls what would you expect to find in the hay analysis?
low A.D. Fiber and N.D. Fiber
Which of the following increases the possibility of genetic resistance developing in a pest?
a. asexual reproduction
b. lack of selection pressure
c. long life cycle
d. single gene inheritance of resistance
single gene inheritance of resistance
What is the THC threshold that Missouri growers can grow Industrial Hemp?
0.3%
In cotton production what are DD-60s?
heat unit measurements used to manage and monitor cotton
Symbiotic nitrogen fixation is the process where atmospheric nitrogen is converted to ammonia in the root nodules of ______.
legumes
In most situations, surface soil _______ will be lower after water erosion occurs.
organic matter content
Which elements do plants obtain from the air?
C, H, O
What is the appropriate stage of maturity for harvest for timothy?
Late boot stage
When a hay sample is analyzed in the lab for forage quality only three values are measured (other than Ca, Mg, P and K) The other quality factors are then calculated using those three. Which are the three that are actually measured?
ADF, NDF, Crude Protein
Which of the following actually neutralizes soil acidity when lime is applied?
a. H+
b. CO3-
c. Ca
d. OH-
OH-
Breeding cotton for insect resistance is important because it ______
eliminates the need for spraying that also kills beneficial insects
Which crop(s) needs(s) to be vernalized to reproduce?
a. all of these
b. wheat
c. soybeans
d. corn
wheat
If substantial ammonia is lost after application of UAN, an ____ inhibitor might reduce this loss
urease
What is the appropriate stage of maturity for harvest for alfalfa?
bud to 1/10th bloom
The Universal Soil Loss Equation, A=RKLSCP uses many factors to calculate soil erosion. What does K stand for in the equation?
soil erodibility factor
What does physiological damage to plants by insects refer to?
disrupting the internal natural process of the plant
What kind of erosion removes a thin layer of soil?
sheet
_____ fungicides are absorbed by the plant and distributed internally to prevent disease infection or kill the pathogen without harming the plant?
systemic
What is the appropriate stage of maturity for harvest for orchardgrass?
blooms emerge
Greenbugs, Midge, and Webworms and major pests to which crop?
grain sorghum
Which of these crops are usually grown as hybrids?
a. grain sorghum
b. soybean
c. corn
d. a and c
e. a and b
a and b
What kind of wheat do you make spaghetti, macaroni, and noodles from?
duram
If you planted a soybean variety in extreme northern Missouri in May that was suited for extreme southeast Missouri what would happen?
it would stay green until frost
What is not an advantage of a bale age harvest system?
a. Increase of 5-6% crude protein in red clover and alfalfa bale age
b. Allows for harvest of higher moisture forage
c. Improved digestibility
d. Reduces ergo valine toxins in the forage
Reduces ergo valine toxins in the forage
Hemp is a dioecious plant. What does that mean?
It has separate male and female plants
By which method is rice planted?
a. drill-seeded
b. water-seeded
c. planted in 30-inch rows
d. a and b
e. a and c
a and c
If alfalfa is the most productive legume why isn’t it grown more widely?
a. it doesn’t thrive on acid or non-fertile soils
b. the seed is expensive
c. it is subject to winter kill
d. all of these
all of these
The part of a chromosome that determines individual plant characteristics is called a/an ___?
gene
When would not be a good time to reduce soybean planting rates?
when you are no-tilling
What is the best way to avoid herbicide resistance by weeds?
a. Using multiple effective modes of action
b. Coming back with a post emergence herbicide
c. Using a preemergence herbicide
d. all of these
all of these
Which of the following pesticides would have the highest probability to move to ground water?
a. insoluble, persistent
b. insoluble, not persistent
c. soluble, persistent
d, soluble, not persistent
soluble, persistent
When is the average date for planting rice in Missouri?
April 15-June 10
What is the appropriate stage of maturity for harvest for red clover
1/4 to 1/2 bloom
What are the benefits of cover crops?
a. erosion control
b. long term soil improvement
c. lower cost of production
d. b and c
e. a and b
a and b
As forage harvest is delayed what do you think would happen to forage quality?
NDF, ADF, and ADL would increase
What is the appropriate stage of maturity for harvest for Reed Canarygrass?
Seed heads emerged
What are N E Lact., N E Gain, and N E Maint. estimated from?
A.D Fiber
A local expert trained to aid the producer in making cotton production decisions is called a _______.
Cotton consultant
What is a cover crop?
They are crops planted when a crop field would otherwise be fallow
What is not a way that producers can control soybean cyst nematodes?
a. spray broadleaf weeds in nearby fields
b. rotate soybeans with nonhost crops
d. all of these are control measures
c. work uninfected fields first to avoid spreading in soil
d. use resistant soybean varieties
spray broadleaf weeds in nearby fields
If a forage has a nitrogen concentration of 2% what then is the Crude Protein concentration?
12.5%
At which of the following soil pHs would phosphorus be most available for plant uptake?
a. 7.2
b. 6.8
c. 7.8
d. 6.2
6.8
How many sq feet are in an acre?
43560 sq ft
How many feet are in a mile?
5280 ft
How many oz in a gallon?
128 oz
How many qts in a gallon?
4 qt
How many oz in a quart?
32 oz
How many oz in a pint?
16 oz