1. AHS Agriculture

2.  What are the basic needs of plants and various factors that make up their environment?

3.  What factors have the greatest impact on plants?

4.  Factors that have greatest effect on plants are:  Water, nutrition, medium, temperature, light, humidity, insects and diseases

5.  70-90% of fresh weight & major component of green plants.  Medium for biochemical rxns  Transports nutrients & manufactured food

6.  Allows sunlight to penetrate leaves & green stems to reach chlorophyll & power production of food  Vapor cools plant

7.  Stress plants  More susceptible to disease & insect attacks  Slow process of photosynthesis

8.  16 elements from soil of fertilizer  Nitrogen, phosphorus & potassium needed most often

9.  Growth greatly influenced by heat  Plants unable to maintain cells at uniform temp.

10.  Heat reproduction parts when ready for fertilization  Cool leaves by transpiration (not constant temp)  Roots less affected – soil

11.  Select plants adapted to area  Some plants require # of days at cold temp to flower (impatiens) 

12.  Growth increases as temp increases up to 86*F  Above 86*,slows or stops  90*-100* severely damage

13.  Reduced growth  Can result in death of plants  Cold-hardy plants can die if sudden drop in temp also

14.  More light= grow & flower better  Too much direct light= damage to shade plants

15.  Spring longer days= growing & flowering  Fall shorter days = perennials, shrubs & trees hardening off & preparing for dormancy & cold temps

18.  Why is soil important?

19.  Soil or soil substitute plants are grown in

20.  Casualty of American agricultural revolution- loss of native soil fungi  Allow plants to grow w/ less water, fewer added nutrients, & fewer pesticides

21.  Can now control plant diseases through use of compost & mulch  Also improves drainage

22.  Sand, silt, clay, organic matter, living organisms & pore spaces that hold water & air  Classified on % of sand, silt & clay

23.  Sand larger then silt, clay smallest  Clay important to hold water & nutrients for plant

24. topsoil – layer plowed/tilled, contains most organic matter Subsoil- oxygen available, roots expand here Soil bedrock/lower subsoil- roots expand until rock, hard clay or water prevents

25.  50% solid material (minerals, organic material)  50% pore space  Amount of moisture held depends on soil type

26.  Silt & clay make up less then 20% of material  Drain well  Little capacity to hold moisture & plant food

27.  At least 30% clay  Heavy soil  Poor drainage & aeration capabilities  Holds fertilizer, plant food & water well

28.  Most desirable  Mixture of equal parts of sand, silt & clay

30.  Answer the questions using the texture triangle to determine the type of soil

32.  What are the varieties of medium?

33.  Drainage & aeration- add organic matter to soil (aggregation)  Lime & gypsum (calcium sulfate)  Raising beds  Ditches

34.  Moisture retention- organic matter  Peat moss- 15x its weight  Animal manure, green manure, peat moss, sawdust- good organic matter

35.  Yellow or pale leaves = nitrogen deficiency  Purple under leaf= phosphorus deficiency

36.  Nematodes – tiny animals  Insects  Crop rotation & compost to control  Chemicals as last resort

37.  Mix uniform  Sterile  Lighter in weight  Good moisture retention & drainage

38.  Blown over bc light  Minor plant food elements missing (iron, sulfur, zinc & calcium)  From mixes to soil- hesitate to extend roots

39.  Perlite- gray-white material of volcanic origin. To improve aeration

40.  Peat Moss- partially decomposed vegetation preserved under water  High moisture-holding capacity, 1% nitrogen, low in phosphorus & potassium

41. Sphagnum moss- dehydrated remains of acid bog plants in shredded form for seeds Sterile, lightweight, controls disease well, excellent water- holding capacity acid

42.  Vermiculite- light, expanded material with neutral pH  High moisture-holding capacity

43.  Limestone- calcium carbonate (CaCO3) raise pH  Tree Bark- pine or oak trees  Slow-release fertilizers- plant food gradually made available

44.  May contain 2 or more of above ingredients  Different plants have different requirements

45.  May

47.  How can we ensure proper fertilization?

48.  Most important plant food element  Plant food must be dissolvable in water

49.  Major elements  Secondary nutrients  Minor nutrients

50.  Show % of or lbs per hundred weight of 3 major elements in large #’s on bag or container

51.  5-10-5  5% nitrogen  10% phosphorus  5% potassium  Other 80% filler material to help spread plant food evenly

52.  Most noticeable effect on plants  Encourages vegetative growth  Dark green leaves  Soft, tender growth, good quality for crops, better tasting

53.  Too much:  Lowers resistance to disease  Weaken stem  Lower quality of fruits  Delay maturity/damage to plants

54.  Lost by leaching (washing out)  Not held by soil particles  Legumes (beans, peas) manufacture own nitrogen

55.  Held tightly by soil  Encourages plant cell division  Flowers & seeds  Hastens maturity, offsetting quick growth from nitrogen

56.  Encourages root growth  Makes potassium more easily available  Increases resistance to disease  Improves quality of grain, root & fruit crops

57.  Can dry out roots by pulling water from roots  Insufficient- purple coloring, reduced fruit, flower & seed production, plant disease, poor quality fruits

58.  Increases resistance to disease  Encourages strong, healthy roots  Essential for starch formation  Development of chlorophyll  Encourages use of carbon dioxide

59.  Deficiency as yellowing on edge of leaves

60.  Affects soil acidity  Availability of plant food elements

61.  Pg. 45 pH scale  Best growth 5.6-7

62.  Sulfur, iron sulfate or aluminum sulfate used  Flushing with low salt irrigation also works

63.  Lime to raise pH  Can also release phosphorus when too acid  Decreases aluminum & iron  Activates soil organisms & encourages release of plant food

64.  Do not lime blueberries, azaleas, & rhododendron  May cause iron deficiency if pH above 6

65. DD

67. Lesson Essential Question  What does a plant need aboveground to survive?

68. Factors  Temperature  Light  Humidity  Plant Diseases  Insects  Gases/Particles

69. Temperature  One of strongest affects  Some grow in cooler temps  Some prefer hot temps  Near & below freezing stops plant growth  86* good temp, above plant growth slows

70. Light  Must be present to produce food  Too much can destroy plant  Some plants only bloom when days shorter (chrysanthemum)

71.  Photoperiodism – response to different periods of day & night in terms of growth

72. Light  Grow towards light  Flavanoids- natural sun blockers in leaves  Enzymes to repair leaf damage from UV lgiht

73. Humidity  Most not affected  40-80% humidity best  High humidity will spread fungus

74. Humidity  Relative humidity- amount of moisture in air as compared with the % of moisture that the air could hold at same temp if completely saturated

75. Plant Diseases & insects  Reduces production  Stem injury may girdle (circle) or clog up a stem & kill plant  Prevent- varieties resistant to diseases and/or insects, crop rotation or chemical sprays

76. Gases & air particles  Carbon Dioxide (CO2) vital  Some add to greenhouse  Damage: sulfur dioxide (coal furnaces) Carbon monoxide (cars)  Consider fumes

77. Adaptability of plants  Plant Heat-Zone Map (AHS)  Plant Hardiness Zone Map (USDA)  Using both, #’s set up to indicate where plants grow best

78. #’s  First 2= cold hardiness 1 st - coldest zone, 2 nd - least cold zone  Second set= heat tolerance & requirement. 1 st - hottest zone, 2 nd - lowest heat zone

79. #’s  EX: Cornus florida, East Coast dogwood (5-8, 8-3)  Other factors will affect plant growth also

80. Activity  Carbon