tering urban plant vegetation may result in a 3-fold increase domestic water use during the summer months (Kjelgren et, 2000; White et al., 2004).

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1 ackground & Perspective: tering urban plant vegetation may result in a 3-fold increase domestic water use during the summer months (Kjelgren et, 2000; White et al., 2004). n Antonio is a recognized leader in water conservation via th n Antonio Water System (SAWS) Conservation Program. n Antonio passed a 2006 Water Conservation Ordinance wit pact on turfgrass.

2 visions: urfgrass associated with new construction after nuary 1, 2006 inimum soil depth of 4-inches beneath the turfgrass urfgrass established after January 1, 2007, shall have mmer dormancy capabilities. Summer dormancy efined as the ability of turfgrass to survive without ater for a period of sixty consecutive days between t onths of May through September. eginning January 1, 2007 SAWS will maintain a list f turfgrasses that have demonstrated summer ormancy capabilities.

3 turfgrass drought tolerance et at 60-day recovery period for survival llowing a 60-day drought. he 60-day periods were arbitrary and not an dustry standard! commercially available turfgrasses ultivars in the San Antonio market ative soil depth - a newly established site oot barrier at a depth of 4-inches.

4 Restrictions tering with an ation system or nkler is allowed once a week re 10 a.m. or r 8 p.m. on your gnated watering as determined our address:

5 Restrictions tering with an ation system or nkler, permitted once a week on designated ering day during hours of 3 a.m. a.m. and 8 p.m. 0 p.m.:

6 Restrictions tion with a soaker hose, end sprinkler or ind irrigation system ed every other week ning on the second day after the Stage III een declared a.m. to 8:00 a.m. and p.m. to 10:00 p.m. held hose, drip tion system or 5 gallon et Tuesdays, Thursdays, days during Stage III.

7 about Smart conservation & Knowing about how much eded oducing a healthy grass that can persist on the least amo rigation water nowing how to water your lawn efficiently for the good of wn eeping applied water on your landscape

8 plants are nearly 80% water by weight! s use water to take up soil nutrients s cool themselves by moving water out h tiny pores in the leaves (a process transpiration) iration cooling is essential for the overall and maintenance of turfgrass. lost though transpiration is greater under er-like conditions high temperature,, windy with low humidity. is also lost from soil reservoir by oration from soil surfaces. transpiration (ET) is a term that describes ater loss from the turf soil system.

9 Water Wise ntial Evapotranspiration (PET) are estimated by weather station hroughout Texas. See the PET te at: stimates the maximum amount ter lost from the soil oration) and grass plant piration) umbers are reported in inches ter lost per day er week or month is also only estimated.

10 no Farms nd own k risto rales elo onio r Aquifer Golf Course Center

11 ntial Evapotranspiration, ETo (also abreviated as PET), is ate of the water requirements of a 4-inch grass growing in soil under well-watered conditions. A turf coefficent (Tc) ed to relate pet to the water requirements of a specific tur lished lawns, the Tc remains constant throughout the activ ing season of the grass. For warm season grasses, such as stine, the Tc is 0.6 throughout much of the year, while the ool season grasses, such as rye, is 0.8. ever, we seldomly apply this amount of water to lawns. W use we do not want maximum production of grass clippin ad, we want to maintain a healthy, attractive turf with as li r as possible. Thus, we modify the coefficent by specifyin ity Factor. complete equation is: ETo x Tc x Qf = turf water requirem

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13 ormant, uiescent, Severely maged, or Dead Recovery Possible Moderately Dry Optimum Health Exces So Mois Low <<<<<<<<<<<<<<<<<<<<<<<Soil Moisture >>>>>>>>>>>>>>>>>>>>> High ation epletion m Death More Discoloration Leaf Firing Dormancy Decreased PS Increased RS CH 2 O Reduction Discoloration & Decreased: Growth Recovery Pest Resistance Stress Resistance Maximum: Growth/Rooting Recuperation Density Uniformity CH 2 O Balance Stress Tolerance Discolora Decrease Growth Rooting Recover Pest Res Stress R

14 Water Stress s of water stress - called wilt will likely appear in local s -watered without watering the whole lawn er stressed grasses usually show visual signs of wilt af rolling ss of turgor pressure in the plant causes wilting. When ass wilts footprints in the turf do not spring back ater stressed or wilted areas turn color from green to a uish/purplish color to off color brown patches. PORTANT: Lawn grasses, can withstand periods of w ess without permanent damage to the plant.

15 roots and the soil holds water for the roots! w you water affects grass root growth and functio drainage or compacted reduce root growth and s initiate growth from the n. s function best when the is healthy and the soil has its pore spaces of the roots are usually in pper 1/2 of the total root m depth - see figure to

16 Water Deeply ant water to reach 6 to 8 inches into soil eep Watering Deeper roots Plants more resistant to stress hort applications Shallow roots Plants not resistant to stress

17 ed to apply and how we pay for water! pay for water in gallons (per gal water used) is a reference of plant use and oration - it is measured in inches. is a term that is linked to urements of inches of water as a ence point for healthy plant th. inch of water over 1 acre equals,154 gallons R 0.62 Gallon/ft2 62 times 128 ounces =79.3 ounces 1 square foot of turf 1 Inch = 80 ounces/ft2

18 esting: gation controllers are cally set to water es for a period of time mber of minutes). me watered rarely links k to gallons watered! challenge is to erstand the linkages hese terms!

19 Much Water Is Applied Over Tim s Catch Cans to sure water applied over in inches! cks the uniformity of r distribution for each kler head. rmines an irrigation em s application rate ach zone. s understand irrigation em weaknesses and gths and the need for

20 inch of water varies with lawn size! cape size are feet) Water/sq. ft./inch (gallons/sq. ft.) Total Water PET Total Wa , , , , , , , ,

21 w much water does my lawn need ypically during the summer 1.0 per week, applied in two applications works well. pring and Fall will require much less depending on rainfall. inter, probably not at all.

22 e best time to water is in the early morning (4:0 0 am) ind is low, water pressure is highest, consumer deman w, evaporation rates are low. tering in the evening laces water droplets on the leaves for extended periods me, which enhances disease. ter as deeply and infrequently as possible! f possible, water to a depth of 6 to 8 inches into the soil ou may have to use additional cycles on the irrigation ystem to achieve this so as to avoid runoff.

23 system puts out? lace several small straight sided cans in the law d the run the system for 15 minutes. Then easure and record the depth of water in each ca d determine the average depth. Multiply the epth by 4. Then you will know the rate of plication. ou must do this for all zones!

24 Cont. xample: you place 5 cans in the lawn and run a ne for 15 minutes, you get the following depth.25 (1/4 ),.3,.20,.25,.25 = / 5 =.25 You collected 1/4 (.25 ) in 15 minutes..25*4= 1.0 per hour is your application rate!

25 ow much water does my lawn need? Cont. nother simpler option would be to place a can he lawn and run the system until you catch 1 o ater! Then you will know how long it takes to pply 1 of water.

26 ere I live the soils are mostly clay, i t out 1 of water on the lawn, most o it runs off! What can I do? t your controller to run multiple short cycle ith at least 1 hour between run times, that w d up to the amount you want to apply. This ay you can apply the desired amount of wate ithout losses to run off.

27 here I live the soils are shallow, if I t out 1 of water on the lawn, most it runs off! What can I do? shallow soils you can apply only a limited mount of water, before the soil reaches field pacity, after that point water will move eith rough cracks in the bed rock or laterally off te. You will have to water more frequently ith smaller volumes.