Pasture Species and Cultivars Flashcards
Define apical meristem
growing point which is a translucent dome of cells
Grasslands Kara - species, growth habit, flowering and grazing
Cocksfoot, erect, mid-season flowering, rotational grazing (not sheep)
Name the most common Italian-type hybrid ryegrass and its persistence range
Grasslands Manawa - 2-3 years
Name 1 early and 1 late flowering cultivar of Timothy
Grasslands Charion early, Grasslands Kahu
What is different about the flowering dates of Timothy than Ryegrass?
Even the early flowering variety of timothy flowers much later than Ryegrass
Grasslands Nui - species, flowering, grazing, ploidy
Diploid perennial ryegrass, early flowering, rotational/set stocked
Ceres Torpedo - species, flowering, grazing / growth habit
Tall fescue, mid flowering, rhizomes so requires lax grazing to increase Summer and Autumn growth.
Fertility requirements of PR and IR
medium-high
Fertility requirements of Tall Fescue
medium-high
Fertility requirements of Cocksfoot
medium-high
Fertility requirements of Phalaris
medium-high
Fertility requirements of Timothy
medium-high
Fertility requirements of Prairie Grass
medium-high
What are the environmental requirements for tetraploid ryegrass?
high fertility, high moisture, lax grazing
Nevis - species, flowering, ploidy
Perennial ryegrass, early flowering tetraploid
Quartet - species, flowering, ploidy
Perennial ryegrass, late flowering tetraploid
What is the main legume species found on a steep dry hill country slope?
Sub Clover
What was the pasture yield on a steep dry hill country slope vs a stock camp
5.8t/ha vs 15.6t/ha
What was the ryegras % on high country steep slope vs a stock camp?
43% ryegrass vs 64% RG
Grasslands Advance - species, growth habit, grazing requirements
Tall Fescue, broad leaf, rotational grazing
Grasslands Maru - species, best time of growth
Phalaris, Autumn and early winter
Tall Fescue Establishment temperature?
10 degrees
Describe the trend in age of grass tillers on a plant
The oldest tillers are found at the bottom and newer tillers at the top.
What is found at the nodes?
shoot buds
Explain a phytometer and its location on a grass plant
Make up of nodes, internode and the attached leaf which are stacked like plates. Found on the true stem.
Explain the two components of each tiller leaf
Leaf blade/lamina. Leaf-sheath which wraps around the stem rolled into the pseudostem.
How does the physical structure of a tetraploid ryegrass differ to a diploid?
double the chromosomes, large leaves and seeds. More palatable to livestock.
What is the optimum temperature for annual sub clover?
12-15 degrees
List 3 drought tolerant legumes
Lucerne, red clover, sub clover
List 3 low-fertility grasses
Grazing brome, yorkshire fog, browntop
List 3 grass species which require more than 600mm of rainfall?
Perennial and Italian ryegrass. Timothy
Why does Ryegrass contribute the most to pasture growth during the cool season compared to the rest of the season?
grows fast in spring due to beginning to change from vegetative production to reproductive. Getting stalky which requires a high DM content to lift the seed to the top of the canopy. More suited to optimum temperature of growth, too hot in summer.
Why does WC have a higher DM growth rate over Summer and Autumn than PR?
After the ryegrass tillers have flowered they die. White clover has a higher optimum temp for growth at 25-29 degrees compared to PR so can grow faster when it is hot and moisture is not limiting.
How does the legume content of pasture change at low-high Olsen P levels?
At low Olsen P, there is a low legume content due to lower N fixation. At a higher Olsen P, legume increases and N fixation increases, but this also increases the N available for pasture growth and therefore the clover can get outcompete in the long-term.
What are the main 3 factors used to match species to an environment?
Grazing management, temp response, moisture
What 2 grass species dominate steep-dry low fertility pastures?
Cocksfoot and browntop
What is the optimum temp for white clover?
25-29 degrees
What is the optimum temp for perennial ryegrass ?
18-21 degrees
What rainfall does Lotus require?
1000mm
What aspect of cocksfoot grazing management is important?
Grazing to minimize seed heat as forage quality declines quickly and becomes lower than PR when excess seed head is present.
Grasslands Tekapo - species, grazing management, flowering time
Cocksfoot, sheep hard grazing, early flowering
List 3 high-medium fertility legumes
White, red clover. Lucerne
What is the maximum photosynthetic temperature for Tall Fescue?
26 degrees
In an expiriment by Gray, how much did yield change over how long in response to SSP stopping application
decrease in 4.9t/ha over 4 years
In the expiriment by Gray, how much did the WC and Browntop content change over 4 years after SSP stopped being applied?
18 less white clover, 22% more browntop.
What is Phalaris’s temperature required for establishment
15-20 degrees
List 4 low-medium fertility legumes
caucasian and sub clover, birdfoot trefoil, lotus.
List 4 grass species which must be rotationally grazed
Tall Fescue, Phalaris, Timothy, Prairie Grass
List 5 grass species which are tolerant to hard grazing
PR and IR. Tall fescue, cocksfoot, phalaris
Compare the ryegrass tillers per m2 on high SR and high fertility and Low SR and Low fertility
High SR = 10,500 tiller per m2 and low SR - 2480 tillers per m2
What are hybrid ryegrasses? Why are they added to pasture mixes?
Mix between perennial ryegrass and Italian ryegrass. Added to boost cooler region growth and animal performance during winter.
How to tetraploid ryegrasses change animal intake compared to diploid?
Increase intake by 3-4%
Explain early tiller development of a grass plant
A leaf primordium bulges out of one side of the leaf. A tiller bud begins to form with cells at the bottom of the leaf primordium expanding and dividing. These close over the growing point and lengthens to form a leaf lamina and sheath.
Explain the positions of 5 phytometers at any 1 time
2 in the process of elongation. 1 with leaf emerging into the light. 2-3 with fully emerged leaves.
How can a grass tiller structure be conceptualized to improve grazing management?
A chain of phytometers at different stages of development.
What factors do we consider when matching a particular cultivar to an environment ?
grazing type, insect/pest challenge, drought tolerance, endophytes
List 4 grass species which are low-rainfall tolerant
Tall fescue, cocksfoot, browntop, phalaris
How much tillers are present per m2 in a ryegrass pasture at any one time
4-8,000
Grasslands Ariki - species, type, persistence
Perennial type hybrid ryegrass, 10 years in moist conditions, 1-2 years in dry conditions.
Ceres Atom - Species
Prairie Grass
Compare WC tiller number in a high stocking rate, high fertility area vs a low stocking rate and low fertility area.
782/m2 vs 3740/m2
Concord Wrightson - species and ploidy
Diploid Italian ryegrass
Grasslands Moata - species and ploidy
Tetraploid Italian ryegrass
Define pseudostem
A soft, stem-like structure formed when leaf sheaths wrap around each other in concentric circles.