Shoot growthShoot growth

• After germination, the embryo develops into After germination, the embryo develops into a seedling plant. a seedling plant.

Shoot growthShoot growth

• After germination, the embryo developes into After germination, the embryo developes into a seedling plant.a seedling plant.

• The crown becomes more fully developed.The crown becomes more fully developed.

Shoot growthShoot growth

• After germination, the embryo developes into After germination, the embryo developes into a seedling plant. a seedling plant.

• The crown becomes more fully developed.The crown becomes more fully developed.

• The crown gives rise to leaves, roots, tillers, The crown gives rise to leaves, roots, tillers, and in some cases elongated lateral stems.and in some cases elongated lateral stems.

A highly compressed stem with apical A highly compressed stem with apical meristem, nodes, internodes, axillary buds, meristem, nodes, internodes, axillary buds, and roots. The crown is one of four types of and roots. The crown is one of four types of stems that occur in grasses. stems that occur in grasses.

The CrownThe Crown

A highly compressed stem with apical A highly compressed stem with apical meristem, nodes, internodes, axillary buds, meristem, nodes, internodes, axillary buds, and roots. The crown is one of four types of and roots. The crown is one of four types of stems that occur in grasses.stems that occur in grasses.

Crowns form from the embryo of germinating Crowns form from the embryo of germinating seed, axillary buds and terminals of rhizomes seed, axillary buds and terminals of rhizomes and stolons, and from axillary buds on more and stolons, and from axillary buds on more mature crowns. mature crowns.

The CrownThe Crown

Apical meristemApical meristem

Primordial leavesPrimordial leaves

Axillary budAxillary bud InternodeInternode

NodeNode

Adventitious rootAdventitious root

Primary rootPrimary root

Diagram of a grass crown.Diagram of a grass crown.

TillerTiller

TilleringTillering

• Tillers arise from axillary buds on crownTillers arise from axillary buds on crown

TilleringTillering

• Tillers arise from axillary buds on crownTillers arise from axillary buds on crown• Grow upward between enclosing sheath andGrow upward between enclosing sheath and main axismain axis

TilleringTillering

• Tillers arise from axillary buds on crownTillers arise from axillary buds on crown• Grow upward between enclosing sheath andGrow upward between enclosing sheath and main axismain axis

• Apogeotropic (upwards) growth differs from Apogeotropic (upwards) growth differs from that of stolons and rhizomes that of stolons and rhizomes

TilleringTillering

• Tillers arise from axillary buds on crownTillers arise from axillary buds on crown• Grow upward between enclosing sheath andGrow upward between enclosing sheath and main axismain axis

• Apogeotropic (upwards) growth differs from Apogeotropic (upwards) growth differs from that of stolons and rhizomes that of stolons and rhizomes

• Produces an identical daughter plant which Produces an identical daughter plant which

becomes independent of mother plants CHbecomes independent of mother plants CH22O,O, nutrient, and water supply. nutrient, and water supply.

Initial Tiller Appearance Initial Tiller Appearance

Factors influencing tiller developmentFactors influencing tiller development::• Plant agePlant age• PhotoperiodPhotoperiod• TemperatureTemperature• ManagementManagement

NutritionNutritionMowingMowingIrrigationIrrigation

Tillering in Tall FescueTillering in Tall Fescue

• Cool temperatures: Less than 70Cool temperatures: Less than 70ooFF

• Short days: Less than 12 hoursShort days: Less than 12 hours

• Conditions typical of autumnConditions typical of autumn

Tiller DevelopmentTiller Development

Cultural factors that influence tillering:Cultural factors that influence tillering:MowingMowing

• Decreasing mowing height increases tilleringDecreasing mowing height increases tillering

Tiller DevelopmentTiller Development

Cultural factors that influence tillering:Cultural factors that influence tillering:MowingMowing

• Decreasing mowing height increases tilleringDecreasing mowing height increases tillering

• Extremely close or frequent mowing will reduceExtremely close or frequent mowing will reduce

CHCH22O needed for tiller developmentO needed for tiller development

Tiller DevelopmentTiller Development

Cultural factors that influence tillering:Cultural factors that influence tillering:MowingMowing

• Decreasing mowing height increases tilleringDecreasing mowing height increases tillering

• Extremely close or frequent mowing will reduceExtremely close or frequent mowing will reduce

CHCH22O needed for tiller developmentO needed for tiller development

NutritionNutrition

Tiller DevelopmentTiller Development

Cultural factors that influence tillering:Cultural factors that influence tillering:MowingMowing

• Decreasing mowing height increases tilleringDecreasing mowing height increases tillering

• Extremely close or frequent mowing will reduceExtremely close or frequent mowing will reduce

CHCH22O needed for tiller developmentO needed for tiller development

NutritionNutrition

• N applied to CN applied to C3 3 grasses in fall increases tillering grasses in fall increases tillering

Tiller DevelopmentTiller Development

Cultural factors that influence tillering:Cultural factors that influence tillering:MowingMowing

• Decreasing mowing height increases tilleringDecreasing mowing height increases tillering

• Extremely close or frequent mowing will reduceExtremely close or frequent mowing will reduce

CHCH22O needed for tiller developmentO needed for tiller development

NutritionNutrition

• N applied to CN applied to C3 3 grasses in fall increases tilleringgrasses in fall increases tillering

• N applied to CN applied to C3 3 grasses in spring decreases tillers grasses in spring decreases tillers