Unit 3-Final Exam Study Guide Flashcards
Peat
Partially decayed plant material and composed mainly of organic matter. Used for its high nutrient and moisture holding capacity. Also reduces acidity of soil.
Bark
Made from both softwoods (conifers) and hardwoods (oak) and is used in a variety of potting mixes as a substitute for peat. Is lightweight and contains major elements such as nitrogen, phosphorus, and potassium.
Sand
An inorganic substance made from minerals but lacks carbon. Commonly used component in many potting mixes because it provides good aeration and drainage. Sand is easy to pasteurize and comes in a variety of particle sizes.
Perlite
Made from light rock that is volcanic in origin. Advantages of perlite include its capability to provide aeration and drainage, and it can be pasteurized easily.
Vermiculite
A very lightweight, expanded platelike material obtained by heat-treating mica; it can be coarse or fine. It has a high moisture and nutrient holding capacity.
Substrate systems
Plant roots are surrounded by either inert or organic materials to provide support
Floating system
Plants are put on a raft and grown in the solution
Nutrient Film Technique system
Plants are placed in a trough with a shallow stream of circulating nutrient solution.
Macronutrient
chemical elements that are required in large amounts for normal growth and development of plants.
Micronutrient
chemical elements that are essential for normal plant
growth and development, but they are needed in much smaller amounts than macronutrients.
Nitrogen deficiency symptoms
stunted growth, yellowing of leaves (chlorosis)
Phosporous deficiency symptoms
dark green leaves with purplish color on underside, stunted plants
Potassium deficiency symptoms
marginal burning of leaves, speckled leaves, leaf curling, reduced size.
Magnesium deficiency symptoms
older leaves, yellowing between veins
Mobile nutrient deficiency shows where?
Shows up on older leaves.
Immobile nutrient deficiency shows where?
Shows up on newer leaves.
When the pH of soil is too low, add:
Limestone.
When the pH of soil is too high, add:
Sulfur/sulfur compounds.
Based on a fertilizer grade, determine what each number of the fertilizer stands for.
The first number= Nitrogen, second number=phosphate, third number=potassium.
A fertilizer is complete if:
It contains all three major nutrients.
Broadcasting
evenly spreading the fertilizer on soil surface.
Top dressing
placing fertilizer uniformly around stem of plant
Side dressing
lacing fertilizer in bands and in the sides after seedling emerges.
Banding
fertilizer is placed 2-3 inches on one side of seed.
Describe the benefits of organic matter.
increases water holding capacity; provides pore space; enhancing root growth; regulates soil temperature; releases small amounts of nitrogen and other nutrients as it decays; increases the soil’s ability to hold nutrients; promotes the growth of microorganisms.
