AgScience Applications Objective 3.03 Understand basic horticultural (ornamental, fruit and vegetable) and agronomic principles and practices.

A. Type of Plant Growing Media 1. Soil is the top layer of the Earth’s surface and is the primary medium of cultivated plants. a. Topsoil b. Subsoil c. Parent material

2. Sphangnum moss is used for encouraging root growth under certain conditions

3. Peat moss consists of partial decomposed mosses in waterlogged areas called bogs.

4. Perlite is a volcanic glass material that has water-holding capabilities and used for starting new plants and in media mixes.

5. Vermiculite is a mineral-type mica used for stating plant seeds and cuttings and in media mixes.

B. Amending the Plant Growing Media 1. Most soil amendments are made to add organic matter, specific nutrients or modify soil pH

2. Improper soil/media pH will have the most impact on the availability of nutrients in the soil/media.

3.The pH is the measure of the degree of acidity or alkalinity are made more acidic (lowering the pH) by adding sulfur or aluminum sulfate.

4. soil/media with high alkalinity are made more acidic (lowering the pH) by adding sulfur or aluminum sulfate.

5. soil/media with high acidic level is made more alkaline (raising the pH) by adding lime. Lime is usually applied as finely ground dolomitic limestone that supplies both Ca (calcium) and Mg (magnesium).

C. Fertilizers 1. A complete fertilizer contains the three primary nutrients: N (nitrogen), P (phosphorus), and K (potassium). Ex

2. Organic fertilizers include animal manures and compost made with plant or animal products. Ex: a. Dried cow manure b. bone meal (high in phosphorus) c. blood meal

3. Organic fertilizers are usually slow acting and long lasting forms of N but lacking other primary nutrients (expect bone meal).

4. Inorganic fertilizers have a higher analysis of soluble nutrients that have been blended together for a specific purpose. Ex:

D. Fertilizer Application 1. Broadcasting or evenly spreading over the entire surface of a lawn other growing area.

2. side-dressing is done by placing fertilizer in bands about 8” from the row of growing plants. Popular for field crops like corn and soybeans.

3. Foliar application is the spraying of liquid fertilizer directly onto the leaves of plants.

E. Principle Parts of Plants 1.Roots a.Generally two types- fibrous or tap root systems. b.Their function is to anchor the plant and take in water and nutrients.

2. Stems a. two basic types of aboveground stems- woody and herbaceous. b. the stem supports other plant parts such as leaves, flowers, and fruit. c. through it water and nutrients are carried up to the leaves and sugar made in the leaves is transported down the roots.

3. Leaves a. the leaf manufactures food for the plant by using light energy (photosynthesis). The chemical equation for photosynthesis is: light energy 6CO2 + 6H2O = C6H12O6 + 6O2

b. photosynthesis occurs best in a temperature range of degrees F. c. Leaves are very useful in identifying plants and vary greatly. The leaf margin (edge), shape and arrangement are all important in plant identification.

4. Flowers a. the primary function of flowers is the production of seeds b. the male flower part is the stamen(anther, filament) and the female part is the pistil(stigma, style, ovary.) c. Flowers can be male, female or both d. petals attract insects to aid in pollination

5. Fruit a. the ovary (lower part of the pistil) of a flower matures into a fruit that surrounds the seeds ex. Apple. b. seed develops in the female part(pistil) of the flower. The seed has 3 basic parts 1.Seed coat- protection for the seed 2.Endosperm- food for the seed. 3.Embryo- baby plant

D. Common Plant Science Practices (skills) 1.Transplanting- can be done by hand or machine and is done in all areas of horticulture. It involves moving a young plant from one location to another. Ex. A seedling tomato from a cell pack in the greenhouse into a garden home.

2. Propagation- Is increasing the number of plant species or reproduction of a species. A. sexual- is the use of seeds for reproducing plants.

B. Asexual(vegetative)- is the use of a part or parts of a plant for reproducing plants. This results in an exact duplication of the parent plant. 1) cutting (stem)- vegetative parts that the parent plant uses to regenerate itself. ex. Swedish Ivy. Rooting hormones are often applied to the cutting to speed up the development of roots.

2) Division- is a method of dividing or separating the main part of a plant into smaller parts ex. Liriope

3) Grafting- is the method of joining two plants together to grow as one. ex. Apple trees.

4) tissue culture (biotech method)- is the use of a very small piece of a plant (explant) to produce a large number of new genetically identical plants. ex: Boston Ferns