Test 1 Flashcards
4 reasons Turf grasses are important:
- Provide food.
- Stabilize various environments
- Furnish large group of ornamental grasses.
- Provide the major plants used as turf in lawns,parks, etc.
Turf grasses belong to what family?
how many genera? Species?
Poaceae or Gramineae
600 g, 7,500 species
150 g in us, 1,500 sp. in us
over 100 cultivars for turf managers to select.
What climate zone is Tn in?
Transitional, bermuda, zoysiagrass, tall fescue.
Name grasses in each zone:
Cool Humid:
Warm Humid:
Hot Humid:
CH: bluegrass, fine fescue, tall fescue, ryegrass
WH: Bermuda, zoysiagrass, centipedegrass.
HH: Bermuda, Zoy, centipede, carpet, bahiagrass, seashore paspalum
Describe BermudaGrass:
Cynodon spp.
from: eastern africa to east indies, 1751
9 species chromosomal #s 18-54
advantages of bermuda8:
.5 to 1.5 in cut- low cut height good traffic tolerance drought tolerance rapid recovery times- rhizomes and stolons uses 68% less water than cool season. ph tolerant 5.5-8.5 utilization of effulent water. pesticide and growth regulatory tolerance and disease resistance.
disadvantages of bermuda:
goes dormant when temps fall below 50 degrees
high N reqs .5- 2 lbs N/1000 sq.ft. per gorwing month
encroachment into other grasses.
thatch/mat producing
winter kill potiential
poor shade tolerance
unstable genetics
Scientific names and description of Common bermudagerass:
two cultivars?
C: Cynodon dactylon- 36 chromosomes, medium coarse/density, unsightly seed heads. use in roughs/ball fields. lawns. tetrapolid
seed head 3-5 spikelike racemes.
Yukon and Riveria- more cold tolerant.
Scientific names and description of hybrid bermudagerass:
H: Magennis bermudagrass, (C.Dactylon x C.Transvaalensis)- 27 chromosomes, triploid -Better disease resistance, - finer texture and darker color -tighter density -no viable seed Tiffgreen(328)-- TifWay(419)---TifSport
Ultra dwarf from location: benefits?
Texas-
Carolina-
Hawaii-
Champion
carolina
Hawaii
can be mowed under .187 to .1’’
Characteristics of ultradwarfs-
higher shoot-leaf density
slow vertical growth
increased stoloniferious growth compared to rhizomes
needs intense grooming and mowing less than 3/16’’
Bermudagrasses from Kansas state-
why?
Midfield, Midiron, Midlawn, Midway
shade/ cold tolerance
Zoysiagrass advantages
Best cold tolerance of warm season, good cold,shade, and salt tolerance slowgrowing tolerates moist soils medium to fine texture,wear resistance very dense and prevents weeds.
Zoysiagrass disadvantages-
medium to high matinence needs reel mower heavy thatch poor drought tolerance slow establishment nematode, brown patch, and dollarspot susceptible.
Zoysiagrass manilagrass-
Zoysia matrella fine leaf high matinence less cold hardy diamond, Zeon- putting green
Hybrid Zoysiagrass-
Zoysia japonica x Z. tenuifolia
good shade, dark green
high maint, thatch
Emerald.
Bahiagrass-
3 advantage-
4 disadvantages
Paspalum notatum - v shaped seed head.
- drought tolerant
- deep rooting
- tolerant of dry,sandy soils
- difficult to mow- tough seed stalks
- coarse texture
- poor salt tolerance
- mole cricket damage
Centipedegrass-
3 adv.
4 dis.
Eremochloa ophiuroides ph 5.5, acidic soils 1.seeded or sodded 2.low maintence 3.slow growth 1. poor drought tolerance 2. Iron deficiency sensitive 3. range limited by cold tolerance. 4. stolon growth only
St. Augustinegrass
3 adv.
3 dis.
Stenotaphrum secundatum 1. adapted to alkaline, sandy soils 2. shade and salt tolerant 3. dark green color/dense sod w/ good appearance. 1.Coarse texture 2. cold and traffic wear sensitive 3. sensitive to many herbicides. pest problems. raleigh- shade/cold/chinchbug
Creeping Bentgrass-
Cool season grass, (C3) Stoloniferous fine textured year round green color, superior playing surface.
causes of bentgrass decline 6-
Heat mowing/scalping humidity shade salinity air circulation
Cool season vs. Warm season-
Air temps-
Soil temps-
Cool- 60-75 Warm- 80-95
Soil-50-65 75-85
Tall fescue-
advantages
Testuca arundinacea
- year round color w/ irrigation
- established by seed/ sod
- wear resistant
- Endophytic fungi for insect bio-control
- low fert req.
tall fescue disadvantages-
- summer irrigation needed.
- bunch type growth
- goes semi-dormant during summer
- brownpatch disease.
- white grub susceptible
Kentucky Bluegrass-
4 adv.-
Poa pratensis cool season- most widely used vigorous rhizome system 1. year round color- when irrigated 2.established by seed or sod. 3.fine to coarse texture 4. better cold tolerance than ryegrass or tall fescue.
Ky Bluegrass dis adv.
- summer irrigation needed
- semi dormant in summer
- thatch problems
- not tolerant to close mowing heights
- diseases- rust and leaf spot.
Perennial Ryegrass
3 adv-
Lolium perenne-
short lived, medium texture,
1.fast establishment
2.tolerates lower mowing height than kyb or tF
3. Used to overseed bermuda tees/ fairways.
Rerennial Ryegrass disadv. 3-
- doesnt tolerate drought
- doesnt tolerate extreme temps
- thin or damaged areas must be reseeded.
Annual BlueGrass-
Rough stalk Bluegrass-
Poa Annua -weed in some areas prolific seed heads -tolerates close mowing -poor heat/disease tolerance
Poa trivialis-bright green, bremuda overseed
Seashore Paspalum-
Paspalum vaginatum -Salt tolerance -Argentina -poor herbicide tolerance/cold tolerance SeaIsle 2000
Seashore Paspalum ADV
Salt tolerance to 34,500ppm low fert req great drought tolerance Strips easily Good playability
Seashore paspalum Limitations-
Lack of selective bermudagrass control minimal shade tolerance limited cold tolerance slower green up than warm season- 2 weeks later seedheads/thatch
How much rain do we normally get :
50-65 inches
Buffalograss-
low maintenance,
10-25 inches of rain yeaarly
stolons and seeds(burs)
Buffalograss adv-
low main, water/fert needs
deep rooted, good drought tolerance
seeds available
tolerates soil textures and pHs, prefers alkaline soil
Buffalo Dis-
Cold ,
rainfall over 25 in
goes dormant during drought
thin open growth
Native Warm season grasses-
Big bluestem- 6ft
Little Bluestem- 2ft
Broomsedge
Weeping love grass-2ft
Switchgrass
Indiangrass
Other cool season grasses
Orchardgrass
Timothy
Blue Fescue
Junegrass
-use a mix
Study of plant germination growth and development.
What 3 processes does this include
Plant Physiology
Photosynthesis, Transpiration, Resipation
Describe which processes cool season grasses and warm season grasses undergo during the Winter and summer:
Winter cool- Photosynthesis/ Summer cool- Respiration
Winter warm- Respiration /Summer warm- Photosynthesis
Describe Photosynthesis-
Light is converted into usable energy(carbohydrates)
produces O2
occurs in chloroplasts
Light reaction- thylakoid membrae
Dark Reaction- Stroma
Light reactions produce ATP and NADPH, which enter the calvin cycle and become NADP, ADP that go back to light reactions. Calvin cycle produces Glucose.
What is a stack of thylakoids-
Granum
What wavelenghts are photosynthetically active radiation?
WHat colors do plants absorb-
380-775
red and blue, mostly red=low energy= easier to process
Bermuda needs 8 hours min
Name the light absorbing pigments-
Chlorophyll a and b(green)
Carotenoid(light yellow to orange) less but broaden spectrum.
Describe the Calvin Cycle-
Transmission of electrons in the stroma to produce glucose.
Describe the cycle used by cool season grasses-
C3 cycle
- forms 3 carbon sugar or 3-PGA
- 6 carbon sugar for sucrose, starch, cellulose
- ADP AND NADP are cycled back to light portion.
6CO2 +12NADPH+12H+18ATP+H20= C6H1202+17Pi+18ADP+12NADP
Describe the cycle used by warm season grasses-
C4 cycle
- 4 carbon sugar (OAA)-
- glucose used for starch and sucrose
- Needs higher temps and light intensities.
C3 plants:
leaf anatomy-
large are spaces and less CO2 conc.
Optimum temp=59-77
not as efficient.
Have RuBP carboxylase- which is sensitive to CO2 and 02
C4 plants
Leaf anatomy-
optimum temps-
Krans anatomy- mesophyll around bundle sheath cells, concentrates CO2
temps= 85-117
Has PEP carboxylase only sensitive to CO2, more efficient
Compare C4 to C3-
In C4 leaf veins are closer together and surrounded by a layer of bundle sheath cells. less airspace= higher concentration of CO2 and more efficiency.
C4 plants have smaller stomal openings, thus less water loss.
C4 less overall N content. =use N more efficiently
Reversal of photosynthesis where sugars and staches are synthesized for plant energy-
describe when warm and cool season do these-
Respiration
Glycolysis+ Krebs Cycle+ Oxidative Phosphorylation
warm: spring and fall when less light is available.
cool-during the summer to fight heat when stoma are closed.
After two turns the end result is a net sum of 36 ATP
Describe photorespiration between C4 and C3 plants-
on bright, hot, dry days C3 plants reduce transpiration by closing the stomates so CO2 levels drop and O2 levels increase.
temps rise, c3 plant lose efficiency because faster CO2 loss by photorespiration.
stomates must open to allow more CO2 but then plant loses water.
C4 plants lose less water per unit of CO2
Describe growth patter of warm vs cool season:
Warm peak in summer
Cool peak in Spring and Fall (spring slightly higher)
fert cool season 1 lb in spring, 2 lbs in fall
a group of cells which are able to divide and enlarge-
where are these located in grasses-
meristems
top of crown
intercalary meristem- between leaf blade and sheath
roots that develop out of the crown-
describe the primary root-
what do roots need?
Adventitious
a root that develops out of the seed then withers.
oxygen for respiration
roots are the immune system of the plant.
Rooting: Optimum soil temps- Soil pH- Nutrients- Light-
warm-75-85 / cool 50-65
pH 5.0- 8.0
K, P, Fe, Ca
shade discourages deep rooting.
Which type of grass have larger root diameters and greater rooting depth?
Warm,
total length, number of root hairs, total surface area
What do roots need from shoots?
What do shoots need from roots?
When is shoot growth favored over root growth(3)
roots need carbohydrates, shoots need water and minerals
soil temps above optimum, close mowing height,(less Ps)
Low light conditions(less Ps = less carbohydrates)
the process of a turfgrass producing new stems and leaves? few factors that promote this-
Tillering
shade increase, morderant N levels, Longer days, decreases as soil dries.
Max soil temp for root growth in cool season-
70-75
Max Air temp and Soil temp for Suggested planting
Cool Air-75-80, Soil 60-70/ Warm Air-80-90 Soil 70-80