Primary Cultural Primary Cultural PracticesPractices

MowingMowingFertilizationFertilizationIrrigationIrrigation

MowingMowing

Most basic but has the Most basic but has the greatest effect on how much greatest effect on how much

we irrigate and fertilizewe irrigate and fertilize

Why do we Mow?Why do we Mow?

• maintain top growth within specific maintain top growth within specific limitslimits

• control undesired vegetationcontrol undesired vegetation• to sustain an ornamental or to sustain an ornamental or

recreational turfrecreational turf

EquipmentEquipment

• reel Mower reel Mower • rotary Mowerrotary Mower

Turf Response to MowingTurf Response to Mowing

• grass tolerates mowinggrass tolerates mowing• mowing is always a stress – cuts the outer mowing is always a stress – cuts the outer

cuticle of the grasscuticle of the grass• creates point of entry for diseasecreates point of entry for disease• temporary cessation of root growthtemporary cessation of root growth• temporary water loss from cut endstemporary water loss from cut ends• reduced water absorption by rootsreduced water absorption by roots• loss of photosynthetic tissueloss of photosynthetic tissue• reduces ability of plant to produce reduces ability of plant to produce

carbohydratescarbohydrates

When you Mow:When you Mow:

• rooting is decreased as mowing rooting is decreased as mowing height is loweredheight is lowered

• carbohydrates that would go to carbohydrates that would go to rooting are instead used to produce rooting are instead used to produce a denser turf to compensate for a denser turf to compensate for foliage loss.foliage loss.

Mowing Tolerance RangeMowing Tolerance Range

• lowest and highest mowing heightslowest and highest mowing heights• below range:below range:

-turf will thin during stress-turf will thin during stress

-weed invasion-weed invasion

-scalping will occur-scalping will occur

Scalping: Scalping:

• removing more than 33-40% of removing more than 33-40% of grass, stops root growth for up to 6-grass, stops root growth for up to 6-14 days.14 days.

• scalping is caused by lowering your scalping is caused by lowering your mowing ht. too quicklymowing ht. too quickly

• can seriously damage or kill turfcan seriously damage or kill turf

FERTILIZATIONFERTILIZATION

Primary determinate in turf Primary determinate in turf persistence and quality persistence and quality

Elements involvedElements involved

• 13 elements are referred to as 13 elements are referred to as mineral nutrients, they are in the mineral nutrients, they are in the soil and taken in by the root systemsoil and taken in by the root system

• macro- N, P, K, macro- N, P, K, • secondary macrosecondary macro - - S, Mg, Ca S, Mg, Ca• micro – Mo, Cu, Zn, Mn, B, Fe, Clmicro – Mo, Cu, Zn, Mn, B, Fe, Cl

NITROGEN (N)NITROGEN (N)

• mineral element used in greatest mineral element used in greatest quantity in turf or by turfquantity in turf or by turf

• N is the most mobile of essential N is the most mobile of essential elements in soil and plantelements in soil and plant

DEFICIENCY:DEFICIENCY:

• one of first signs is a yellowing of the one of first signs is a yellowing of the plant –plant – chlorosis:chlorosis: lack of chlorophylllack of chlorophyll

• slowing of growth (based on clippings)slowing of growth (based on clippings)• low densitylow density• rooting can be affectedrooting can be affected• can cause disease development can cause disease development

(Dollar Spot, Rust, Red Thread)(Dollar Spot, Rust, Red Thread)

EXCESSIVE NEXCESSIVE N

• excessive aerial shoot growthexcessive aerial shoot growth• poor root and lateral shoot growthpoor root and lateral shoot growth• higher disease incidencehigher disease incidence• reduced carbohydrate reservesreduced carbohydrate reserves• poor tolerance to heat, cold, drought, poor tolerance to heat, cold, drought,

traffic, and other stressestraffic, and other stresses• possible shifts in turfgrass community exp possible shifts in turfgrass community exp

Bermuda/CentipedeBermuda/Centipede• too much N can cause brown patch diseasetoo much N can cause brown patch disease

PHOSPHORUS (P)PHOSPHORUS (P)

• important in many plant compounds that important in many plant compounds that are essential for plant growth.are essential for plant growth.

• important for helping young plants important for helping young plants maturemature

• relatively immobile in the soil, does not relatively immobile in the soil, does not move as readily as most elements, move as readily as most elements, unlikely to leach from the soil can make it unlikely to leach from the soil can make it harder for plant to reach the P.harder for plant to reach the P.

• grasses have fibrous root system; grasses have fibrous root system; therefore turf fertilizers have less P (ex. therefore turf fertilizers have less P (ex. 16-4-8)16-4-8)

DEFICIENCY DEFICIENCY SYMPTOMS:SYMPTOMS:

• reduced growthreduced growth• dark green color (sickly green), and dark green color (sickly green), and

on rare occasions: purple in coloron rare occasions: purple in color• narrow leaf bladesnarrow leaf blades

EFFECTS OF P:EFFECTS OF P:

• improved disease resistanceimproved disease resistance• helps with heat, cold and drought helps with heat, cold and drought

tolerancestolerances

POTASSIUM (K)POTASSIUM (K)

• second only to N in plantsecond only to N in plant• does not become any part of plant does not become any part of plant

biochemicalsbiochemicals• involved in opening and closing of involved in opening and closing of

stomata.stomata.• role in heat/cold temp, wear role in heat/cold temp, wear

tolerance.tolerance.

DEFICIENCY DEFICIENCY SYMPTOMS:SYMPTOMS:

• difficult to recognize (subtle) difficult to recognize (subtle) • carbohydrate production downcarbohydrate production down• less resistant to plant diseasesless resistant to plant diseases• less tolerant to environmental less tolerant to environmental

stressesstresses• general reductions in growthgeneral reductions in growth

Fertilizer Frequency Fertilizer Frequency

• depends on the turfgrass use depends on the turfgrass use • types of fertilizer sources usedtypes of fertilizer sources used• availability of essential nutrients availability of essential nutrients

Fertilization TimingFertilization Timing

• two restraints: Disease and two restraints: Disease and environmental stress toleranceenvironmental stress tolerance

• cool season grassescool season grasses

-avoid late spring and summer -avoid late spring and summer applications of Nitrogenapplications of Nitrogen

• warm season grasseswarm season grasses

-avoid late summer and fall -avoid late summer and fall applications of Nitrogenapplications of Nitrogen

IRRIGATIONIRRIGATION

The process of adding The process of adding supplemental water when supplemental water when

rainfall is insufficient to meet rainfall is insufficient to meet the needs of the plantthe needs of the plant

Evapotranspiration (ET)Evapotranspiration (ET)

Combination of evaporation and Combination of evaporation and transpirationtranspiration

Factors effecting ETFactors effecting ET

humidityhumiditytemperaturetemperature

windwind

How much water to How much water to apply?apply?

depends on turf grown and depends on turf grown and environmental conditionsenvironmental conditions

• depends on rooting: depth and depends on rooting: depth and extent of root systemextent of root system

• soil type: Coarse textured to fine soil type: Coarse textured to fine textured soilstextured soils

• soil Compactionsoil Compaction

When and how often to When and how often to water?water?

• timing depends on soil and plant timing depends on soil and plant conditionsconditions

• morning is best, avoid afternoon morning is best, avoid afternoon irrigationirrigation

• frequency: Deep and infrequent frequency: Deep and infrequent