ENVIRONMENTAL FACTORS

LIGHT Turf needs at least 4 hours of full sun Bermudagrass 6 hours Bermudagrass 6 hours –‘Tifgrand’ and ‘Celebration’ 60% shade 60% shade

LIGHT Shade Less PS, less CHO Less PS, less CHO Not as stress tolerant Not as stress tolerant Reduced density Reduced density

LIGHT Shade Symptoms Shallow rooting Shallow rooting

LIGHT Shade Symptoms Succulent growth for pests Succulent growth for pests

LIGHT Shade Turfgrass St. Augustine and Carpetgrass best St. Augustine and Carpetgrass best

LIGHT Trees Compete for moisture and nutrients Compete for moisture and nutrients Reduces amount and quality of light Reduces amount and quality of light Allelopathy: chemical warfare Allelopathy: chemical warfare

LIGHT Shade Management Shade tolerant turf, groundcover, or mulch Shade tolerant turf, groundcover, or mulch

LIGHT Shade Management Reduce traffic Reduce traffic

LIGHT Shade Management Raise mowing height Raise mowing height

LIGHT Shade Management Reduce N fertilization Reduce N fertilization –Nitrogen forces growth –Consumes what little CHO is produced in shade

LIGHT Shade Management Root prune trees Root prune trees Reduces root competition Reduces root competition

TEMPERATURE: HEAT High respiration, low CHO production

TEMPERATURE: HEAT Evapotranspiration Evaporation: water changes from liquid to gas Evaporation: water changes from liquid to gas The conversion requires energy and absorbs heat The conversion requires energy and absorbs heat

TEMPERATURE: HEAT Evapotranspiration Transpiration: water evaporates from openings, stomates, of leaves Transpiration: water evaporates from openings, stomates, of leaves Water as liquid goes through plant and changes to gas at stomates Water as liquid goes through plant and changes to gas at stomates Cools plant by absorbing heat! Cools plant by absorbing heat!

TEMPERATURE: HEAT Heat Management Transpiration: provide adequate moisture Transpiration: provide adequate moisture –Syringing, short cycles of irrigation on golf greens

TEMPERATURE: HEAT Heat Management Wind: promote air circulation Wind: promote air circulation –Increase transpiration

TEMPERATURE: COLD Occur when temps below 20F Occur when temps below 20F Turf looks water soaked Turf looks water soaked

TEMPERATURE: COLD Cold damage worse when: Poor drainage Poor drainage

TEMPERATURE: COLD Cold damage worse when: Excessive thatch Excessive thatch

TEMPERATURE: COLD Cold damage worse when: Shade Shade

TEMPERATURE: COLD Cold damage worse when: Excessive fall N Excessive fall N

TEMPERATURE: COLD Cold damage worse when: Close mowing Close mowing

TEMPERATURE: COLD Cold Management Cold hardy turf Cold hardy turf Establish turf Establish turf August last N August last N Apply K Apply K

MOISTURE Maintains cell turgidity (footprinting) Maintains cell turgidity (footprinting) Transports nutrients Transports nutrients Transpiration Transpiration

MOISTURE Wet Turf Lack of oxygen to roots Lack of oxygen to roots Disease Disease Compaction Compaction

MOISTURE Wet Turf Management Install drainage Install drainage

MOISTURE Wet Turf Management Grade surface drainage and re-establish turf Grade surface drainage and re-establish turf

MOISTURE Wet Turf Management Disease resistant turf Disease resistant turf

MOISTURE Wet Turf Management Avoid traffic Avoid traffic

MOISTURE Wet Turf Management Plant groundcover or mulch Plant groundcover or mulch

MOISTURE Drought Resistance Varies among species and cultivars Varies among species and cultivars Remove thatch Remove thatch Encourage deep roots Encourage deep roots –Deep and infrequent irrigation Avoid fertilization during drought unless irrigation is provided Avoid fertilization during drought unless irrigation is provided

MOISTURE Dew Water accumulation in morning hours Water accumulation in morning hours Condensation and guttation Condensation and guttation

MOISTURE Condensation Water vapor content, or relative humidity Water vapor content, or relative humidity Amount of water vapor that can be held by the air is proportional to air temperature Amount of water vapor that can be held by the air is proportional to air temperature

MOISTURE Condensation Increasing air temp, increase water content Increasing air temp, increase water content Temperature drop causes condensation Temperature drop causes condensation

MOISTURE Nutrient-rich water Guttation: diffusion of plant moisture through openings at ends of leaves Guttation: diffusion of plant moisture through openings at ends of leaves Water pressure builds up in roots due to low transpiration Water pressure builds up in roots due to low transpiration

MOISTURE Nutrient-rich water Nutrients enhance disease Nutrients enhance disease Cause minor tip burn (salts) Cause minor tip burn (salts)

MOISTURE Dew Management Syringing greens to wash off nutrients Syringing greens to wash off nutrients Dew whip Dew whip

MOISTURE Frost Dew forming ice crystals at about 38 F Dew forming ice crystals at about 38 F Avoid traffic on heavy frosted turf Avoid traffic on heavy frosted turf Damage leaves, will not kill crown Damage leaves, will not kill crown

Frost symptoms Frost symptoms

SALINITY High salt levels cause turf to weaken and decline in quality High salt levels cause turf to weaken and decline in quality

CAUSES OF SALINITY Salts not leached excess from soil Salts not leached excess from soil High ET rates High ET rates –Leave behind salts

SALINE SYMPTOMS Initially resemble drought stress Initially resemble drought stress –Shoot browning –Narrow, stiff and darker to blue-green

EFFECTS ON PLANTS Inhibits osmotic water absorption Inhibits osmotic water absorption –Can even remove water from roots

EFFECTS ON SOIL Deterioration of soil structure Deterioration of soil structure Clog pores, reduces soil aeration and infiltration Clog pores, reduces soil aeration and infiltration

TURF RESISTANCE Seashore paspalum, bermuda (hybrids more tolerant), St. Augustine, and zoysia Seashore paspalum, bermuda (hybrids more tolerant), St. Augustine, and zoysia

SALINE MANAGEMENT Test water and soil Test water and soil