Agricultural Crop and Forage Practice Exam Flashcards

A set of 30 vocabulary flashcards covering corn and soybean growth, forage quality, tillage, and soil management based on lecture notes.

Nitrogen deficiency

Commonly identified on corn leaves as yellowing from the tip down the midrib.

GDD (Growing Degree Days) Formula

$$\frac{\text{High} + \text{Low}}{2} - 50$$

Inoculants

Substances used to increase fermentation rate and efficiency.

Hard red wheat

The most common wheat class used in many products such as bread.

Grain fill

A process occurring during the reproductive stages $R3$ to $R5$.

Autotoxicity

A condition where the source of toxicity comes from the alfalfa plant itself.

Dry hay baling

The stage where the highest field loss occurs (field cured hay in bale).

Aflatoxins

Toxins that primarily cause liver damage.

Nitrogen dioxide

A dangerous silo gas represented by the mnemonic "NO oxygen" causing lung damage.

Indeterminate soybeans

Soybeans that continue to flower and grow vegetatively simultaneously.

ADF/NDF Relationship

Higher levels of these components lead to lower Relative Feed Value (RFV) and lower quality.

Corn grain content

The component of silage that contributes at least $50\%$ of the energy.

Soybean flower abortion

The process where soybeans abort a large portion of flowers, approximately $45\text{--}60\%$.

Day length

The factor that controls soybean flowering (rather than weather).

Oleic acid

The fatty acid most desirable for cooking stability.

Unsaturated fats

The preferred type of fats mentioned in the context of oils.

V1 Stage

The soybean vegetative stage characterized by having the first trifoliate leaf.

$$86^{\circ}F$$

The temperature at which corn growth peaks.

Drought

An environmental stressor that increases nitrate accumulation in crops.

Broadleaf crops

Crops that fit well in rotation with small grain or grass type crops.

Chisel plow

A specific implement used for primary tillage.

Deep tillage

Systems using tillage implements that work the soil deeply; does NOT describe conservation systems.

Radish and pea

A common fall cover crop mix used before planting corn.

Soybean residue

The most fragile type of crop residue.

Vegetative (V) Stages

Corn growth stages related to the development of leaves.

Reproductive (R) Stages

Corn growth stages related to grain, often referred to as "Refill the kernels."

Trifoliate

A leaf structure in soybeans described as "1 plant, 3 leaves."

Relative Feed Value (RFV)

A measurement that decreases when Acid Detergent Fiber (ADF) and Neutral Detergent Fiber (NDF) increase.

Primary tillage

The category of soil cultivation that includes the use of a chisel plow.

Nitrate buildup

A consequence of drought stress that results in "Dangerous silage."