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Photosynthesis. Germination and Seedling E stablishment. Life Cycles and Phenology. Secondary Compounds. Seasonal Growth Rates. You are here. Seasonality and Life Cycles. Plant Physiology. Forage Quality. Water and Nutrients. Carbohydrates and Allocation. RDM. Grass
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Photosynthesis Germination and Seedling Establishment Life Cycles and Phenology Secondary Compounds Seasonal Growth Rates You are here Seasonality and Life Cycles Plant Physiology Forage Quality Water and Nutrients Carbohydrates and Allocation RDM Grass Anatomy Forb Anatomy Grazing Effects Grazing and Plant Growth Morphology Shrub Anatomy Grazing Resistance Reproduction Grazing Optimization Range Plant Growth and Development
Seasonality and Life Cycles • Terminology • Life Cycles • Seasonal growth rates • Forage Quality • RDM Life Cycles and Phenology Seasonal Growth Rates You are here Seasonality and Life Cycles Forage Quality RDM
The Phenology Handbook, pg 1-15 George et al. 2001. Annual Range Forage Production George and Bell. 2001. Using Stage of Maturity…….. Seasonality and Life Cycles Reading and references SEASONALITY & LIFE CYCLES Return to Course Map
SEASONALITY & LIFE CYCLES • Terminology • Life Cycles • Forage Quality • Seasonal growth rates • RDM Plant Physiology Return to Course Map
Annual Seasonality and Life Cycles Terminology Return to Course Map • Perennial
Seasonality and Life Cycles Terminology Return to Course Map Grass: monocot, most are not woody Forb: dicot, non-woody • Shrub Dicot, woody
Seasonality and Life Cycles Terminology Return to Course Map • PHENOLOGY is the science that measures the timing of life cycle events for plants, animals, and microbes, and detects how the environment influences the timing of those events. • In the case of flowering plants, these life cycle events, include leaf budburst, first flower, last flower, first ripe fruit, seed set, leaf shedding, others.
SEASONALITY & LIFE CYCLES • Terminology • Life Cycles • Forage Quality • Seasonal growth rates • RDM Plant Physiology Return to Course Map
Seasonality and Life Cycles Life cycles Return to Course Map
Seasonality and Life Cycles Annual Life Cycles Return to Course Map • Annuals • Germination • Vegetative • Seedling establishment • Leaf growth • Winter growth is slow • Growth accelerates in spring • Flowering • Seed Set, Drying • Dry and Die
Seasonality and Life Cycles annual life cycle CALENDAR Return to Course Map Timing of phenological events
Seasonality and Life Cycles Perennial Life Cycles Return to Course Map • Perennials • Lives several years • Sexual reproduction • Vegetative reproduction • Stolons and Rhizomes • Winter dormancy • Dry season dormancy • Vegetative phase • Flowering • Seed set and dispersal • Dormancy
Seasonality and Life Cycles perennial life cycle CALENDAR Return to Course Map Timing of phenological events
Seasonality and Life Cycles Phenology and Life Cycles Return to Course Map Phenological events
SEASONALITY & LIFE CYCLES • Terminology • Life Cycles • Forage Quality • Seasonal growth rates • RDM Plant Physiology Return to Course Map
Seasonality and Life Cycles Phenology and forage quality Return to Course Map Crude protein decreases in annual grasses with stage of maturity (see ANR Publications 8019 and 8022)
SEASONALITY & LIFE CYCLES • Terminology • Life Cycles • Forage Quality • Seasonal growth rates • RDM Plant Physiology Return to Course Map
Seasonality and Life Cycles Seasonal growth rates Return to Course Map D1 J1 F1 M1 A1 M1 Peak http://groups.ucanr.org/sierrafoothill/files/67089.pdf
Seasonality and Life Cycles Seasonal growth rates Return to Course Map • Growth rates of perennials in northeastern California
SEASONALITY & LIFE CYCLES • Terminology • Life Cycles • Seasonal growth rates • Forage Quality • RDM Plant Physiology Return to Course Map
Seasonality and Life Cycles Litter: Residual Dry matter Return to Course Map Moderate grazing results in recommended RDM levels Heavy grazing results in low RDM levels Light grazing results in high RDM levels
Seasonality and Life Cycles Summary Return to Course Map • In this section you have learned the differences between annual and perennial life cycles and how plant growth rates and forage quality change as range and pasture plants move through their life cycle.
Photosynthesis Germination and Seedling Establishment Life Cycles and Phenology Secondary Compounds Seasonal Growth Rates You are here Seasonality and Life Cycles Plant Physiology Forage Quality Water and Nutrients Carbohydrates and Allocation RDM Grass Anatomy Forb Anatomy Grazing Effects Grazing and Plant Growth Morphology Shrub Anatomy Grazing Resistance Reproduction Grazing Optimization Range Plant Growth and Development
Morphology Grass Anatomy Forb Anatomy Shrub Anatomy Reproduction Grass Anatomy Forb Anatomy Morphology and Development Shrub Anatomy Reproduction You are here
Briske, 1991. Chp 4. Dev. Morph and Phys of Grasses. Introduction and Developmental Morphology Sections. Skinner and Moore. Growth and Dev of Forage Plants How Grass Grows Reading and references MORPHOLOGY
morphology Grass Anatomy Forb Anatomy Shrub Anatomy Reproduction Plant Physiology Return to Course Map
Please review “How Grass Grows” at the link below. • Overview of the Grass Plant • Shoot Development • Crown • Leaf Formation • Leaf Expansion Dynamics • Tillering • Rhizome and Stolon Development • Flowering • Root Development • Germination Process • Seasonal Development Morphology and Development Grass Anatomy Return to Course Map http://www.files.ahnrit.vt.edu/files/flash/howgrassgrows/howgrassgrows.swf
Apical meristems (flower) Axillary buds (give rise to tillers, rhizomes and stolons) Intercalary meristems or collar (leaf expansion) Some growing points become elevated as the growing season progresses. Buds near the ground are less likely to be grazed Delaying bud elevation reduces risk of bud removal by grazing Morphology and Development Growing Points Return to Course Map
Morphology and Development Growing Points Return to Course Map • Apical meristems (flower) • Axillary buds (give rise to tillers, rhizomes and stolons) • Intercalary meristems or collar (leaf expansion) • Some growing points become elevated as the growing season progresses. • Buds near the ground are less likely to be grazed • Delaying bud elevation reduces risk of bud removal by grazing
Apical meristems (flower) Axillary buds (give rise to tillers, rhizomes and stolons) Intercalary meristems or collar (leaf expansion) Some growing points become elevated as the growing season progresses. Buds near the ground are less likely to be grazed Delaying bud elevation reduces risk of bud removal by grazing Morphology and Development Growing Points Return to Course Map
Apical meristems (flower) Axillary buds (give rise to tillers, rhizomes and stolons) Intercalary meristems or collar (leaf expansion) Some growing points become elevated as the growing season progresses. Buds near the ground are less likely to be grazed Delaying bud elevation reduces risk of bud removal by grazing Morphology and Development Growing Points Return to Course Map Apical meristem rising
In the vegetative phase, shoots consist predominantly of leaf blades. Leaf blade collars remain nested in the base of the shoot and there is no evidence of sheath elongation or culm development. Morphology and Development Vegetative Phase Return to Course Map
Floral induction - Apical meristems is gradually converted from a vegetative bud to a floral bud. During the transition phase, leaf sheaths begin to elongate, raising the meristematic collar zone to a grazable height. Culm internodes also begin elongation in an "un-telescoping" manner beginning with the lowermost internode thereby raising the meristematic zone (floral bud and leaf bases) to a vulnerable position. Morphology and Development Elongation (Transition) Phase Return to Course Map
The flowering phase begins with the conversion from vegetative to floral bud. Much of this is unseen until the emergence of the seed head from the sheath of the flag leaf (boot stage). Within a few days, individual florets within the seed head are ready for pollination. Morphology and Development Reproductive Phase Return to Course Map Apical meristem rising
morphology Grass Anatomy Forb Anatomy Shrub Anatomy Reproduction Plant Physiology Return to Course Map
Morphology and Development Forb anatomy Return to Course Map
Morphology and Development Forb growing points Return to Course Map Growing point or apical bud
morphology Grass Anatomy Forb Anatomy Shrub Anatomy Reproduction Plant Physiology Return to Course Map
Morphology and Development Shrub Anatomy Return to Course Map • Coast live oak resprouts • Chamise resprouts
morphology Grass Anatomy Forb Anatomy Shrub Anatomy Reproduction Plant Physiology Return to Course Map
Long Day Plants Short Day Plants Sexual Reproduction (flowers and seeds) Vegetative Reproduction (stolons, rhizomes) Morphology and Development Reproduction Return to Course Map
Morphology and Development • Reproduction - LONG DAY PLANTS Return to Course Map • Some plants are long-day plants and others are short-day plants. • The long-day plants reach the flowering phenological stage after exposure to a critical photoperiod and during the period of increasing daylight between mid April and mid June. • Generally, most cool-season plants with the C3 photosynthetic pathway are long-day plants and reach flower phenophase before 21 June.
Short-day plants are induced into flowering by day lengths that are shorter than a critical length and that occur during the period of decreasing day length after mid June. Short-day plants are technically responding to the increase in the length of the night period rather than to the decrease in day length. Generally, most warm-season plants with the C4 photosynthetic pathway are short-day plants and reach flower phenophase after 21 June. The annual pattern in the change in daylight duration follows the calendar and is the same every year for each region. Morphology and Development • Reproduction short Day Plants Return to Course Map
Plant populations persist through both asexual (vegetative) reproduction and sexual reproduction. The frequency of true seedlings produced from seed is low in established grasslands and occurs only during years with favorable moisture and temperature conditions in areas of reduced competition from older tillers, and when resources are easily available to the growing seedling. Morphology and Development Reproduction Return to Course Map
Sexual reproduction is necessary for a population to maintain the genetic diversity enabling it to withstand large-scale changes. However, production of viable seed each year is not necessary to the perpetuation of a healthy grassland. Morphology and Development Reproduction SEXUAL Return to Course Map
Morphology and Development Reproduction SEXUAL Return to Course Map • Reproductive shoots are adapted for seed production rather than for tolerance to defoliation • Grass species that produce a high proportion of reproductive shoots are less resistant to grazing than are those species in which a high proportion of the shoots remains vegetative.
Reproduction Vegetative growth is the dominant form of reproduction in semiarid and mesic grasslands Annual plants are dependent on seed production each year for survival. Short-lived perennials depend on seed production. Long-lived perennials rely more on vegetative reproduction. Morphology and Development ASEXUAL OR VEGETATIVE Return to Course Map
Morphology and Development tillering
Bunch grasses spread by the production of tillers. Stoloniferousgrasses spread by lateral stems, called stolons, that creep over the ground and give rise to new shoots periodically along the length of the stolon. Rhizomatousgrasses spread from below ground stems known as rhizomes. Morphology and Development Reproduction ASEXUAL OR VEGETATIVE Return to Course Map
. Morphology and Development Summary Return to Course Map In this section you learned about plant growing points, how plants grow, phases of plant growth and reproduction. You learned that vegetative reproduction in the form of tillers, stolons and rhizomes are more important than reproduction via seeds in most grasslands. You also learned that buds close to the ground are less vulnerable to grazing than when they are elevated.