Introduction to Turfgrass

1. Introduction to Turfgrass

2. Introduction • Turfs were developed to enhance the environment • Turfs are important in human activities • Turfs provide many benefits to those who plant them

3. Benefits (Environmental) • Control wind and water erosion of soil • Reduce glare, noise, air pollution, heat buildup • Increase property values • Increase aesthetic value • Oxygen conversion

4. Benefits (Recreational) • Baseball, football, golf, hiking, polo, rugby, soccer, etc. • Provide cushioning effect reducing injuries • Benefit health by its use in recreational activities

5. Benefits (Ornamental) • Beauty and attractiveness • Provide pleasant environment

6. History of Turfgrass • Turf referenced in Biblical literature • Date to medieval times (200-800 A.D.) • Mowing machine first invented in 1830 (before that mowed by livestock) • Earnest research on turf began in 1880 (Beal, Michigan State) • Most major advances have occurred since 1950’s • Improved cultivars released • Pesticides developed specifically for turf for weed, disease, and insect control • Formulation of fertilizers specifically for turf • Major advances in the mechanization of cultural practices

7. Importance • Cover nearly 32 million acres in the US • Largest irrigated crop in the U.S • That’s 3 times as much as all the corn! • Over 28 billion dollars spent each year on lawns in the US • That’s about $1200/household (of an approx. 25 million households) • One of the only crops that increase with urbanization

8. Terminology • Sod – refers to plugs, blocks, squares, strips, or rolls of turfgrass plus adhering soil that are used for vegetative planting. • Green – Smooth, grassy area maintained for golf, bowling, other sports. • Lawn – Ground covered with fine textured grass and kept closely mowed. • Sward – Grassy surface of a turf that may be composed of more than one species. • Turf – A covering of closely mowed dense vegetation, usually grass, growing intimately with an upper soil stratum of intermingled roots and stems.

9. Turf Quality • Uniformity • Density • Texture • Growth habit • Smoothness • Color

10. Controls of Turfgrass Quality(Inherited characteristics) • Susceptibility • disease, nematodes, insects • Tolerance • Heat, cold • Drought, flood • Shade • Wilt • Salinity • Wear • Recuperative potential • Primarily used for selection purposes

11. Controls of Turfgrass Quality(Environmental characteristics) • Light • Temperature • Water • Nutrient level • Soil aeration • Traffic • Can be controlled at least partially through management/culture

12. Climactic Zones of Turf Adaptation YOU ARE HERE!

13. Cool Season Grasses • Start growth at 5 °C (41 ° F) • Fastest growth rate when temperatures are between 10-25 °C (50-77 ° F) • In climates that have relatively mild/cool summers, two periods of rapid growth (spring and fall) • They retain their color well in extreme cold and typically grow very dense, carpet like lawns

14. Warm Season Grasses • Start growth at temperatures above 10 °C (50 ° F) • Grow fastest when temperatures are between 25 °C and 35 °C (77-95 ° F) • One long growth period (over the spring and summer) • Go dormant in cooler months, turning shades of tan or brown • Typiclaly drought and heat tolerant • Temperatures below -15 °C (5 °F) can kill most warm season grasses.

15. Cool Season • Kentucky bluegrass (Poa pratensis) • Perennial ryegrass (Lolium perenne) • Creeping bentgrass (Agrostis stolonifera) • Tall Fescue (Festuca spp.) • Buffalo grass (Buchloe dactyloides)

16. Cool Season • Kentucky bluegrass (Poa pratensis) • Perennial ryegrass (Lolium perenne) • Creeping bentgrass (Agrostis stolonifera) • Tall Fescue (Festuca spp.) • Buffalo grass (Buchloe dactyloides)

17. Kentucky Bluegrass • “Blue” for the characteristic bluish color of a field when allowed to flower and produce seed. • “Kentucky” due to its widespread occurrence in the relatively fertile limestone soils in Kentucky. • One of the best species for unshaded areas in temperate humid climates • Very aggressive under favorable conditions, spreads rapidly by rhizomes • Looks best mowed at ¾ to 1 ½ inches

18. Perennial ryegrass • Takes its name from European name (“Rai” grass) • Not related to cereal grain • Germinates quickly (7 days or less) • Rapid establishment • Not shade tolerant • Best mowed at 1 ¼ inches or higher

19. Creeping bentgrass • Most commonly used grass on golf putting greens • Strongly developed growth habit of creeping via surface stems that root freely at the nodes • Not well suited to shade • Easiest to injure, difficult to kill • Best when mowed very short (1/2 inch or less)

20. Tall fescue • Useful for more extensive grassed areas that are not maintained as lawns. • Deeply rooted • Broad, flat leaves • Drought tolerant • Grows well in full sun and partial shade • Excellent for areas where other grasses will not grow • Mow at 2 or more inches

21. Warm Season • Zoysia grass (Zoysia japonica) • Bermuda grass (Cynodon dactylon) • Centipede grass (Eremochloa ophiuroides) • St. Augustine grass (Stenotaphrum secundatum) • Bahia grass (Paspalum notatum)

22. Botanical Composition • Monostand – One species of the same variety. • Blend – Two or more varieties of the same species. • Mixture – Two or more species

23. Methods of Establishment • Seed –The mature ovule of a flowering plant containing an embryo, sometimes an endosperm, and a seed coat • Sprig – A single turfgrass stem (stolon, rhizome, tiller, or combination) usually with attached roots and leaves • Sod – Turf harvested as a thin layer composed of a living, dense population of grass palnts with shortened or shallow roots in a growth medium • Plug – A small, usually round piece of turfgrass with adhering soil used in vegetative propagation.

24. Morphology

25. Morphology (continued) • Crown – Compacted series of nodes from which shoots and adventitious roots arise at the base of the culm (stem) of grasses • Tiller – A lateral shoot, or stem, usually erect, arising from a crown bud, common in grasses

26. Morphology (continued) • Rhizome – Usually horizontal, jointed, commonly underground stem of grasses that forms both roots and leafy shoots at its nodes; often enlarged by food storage; may originate from the main stem or from tillers • Stolon – A slender horizontal stem (or shoot) that grows horizontally about the soil surface and is capable of developing leaves, roots, and stems at its tip or at nodes; may originate from the main stem of tillers

27. Morphology (continued) • Bunch type • Ryegrass • Tall Fescue • Spread very slowly through tillers • Spreading • Rhizomes (Kentucky bluegrass, some Tall fescues) • Stolons (Creeping bentgrass) • Both (Bermudagrass, Zoysia grass)

28. Maintenance • Fertilizing • Fertility should be maintained at proper levels. Soil tests should be carried out, and a minimum of 3 lbs./1000 sq.ft. of N should be applied per year • Do a soil test! • Mowing • 1/3rd rule: Only mow off a maximum of 1/3rd the height of the grass at one time • Irrigation • A good system should be able to deliver 1” of water in a 24 hour period

29. IPM • Integrated pest management • An organized program in which the best management methods available (including chemical, physical, cultural, biological, and regulatory) are used to keep pest populations below the economic and/or aesthetic injury level while avoiding adverse effects on humans, wildlife, and the environment.

30. Typical Steps for IPM • Identify key pests to be managed in the turfgrass ecosystem • Define the turfgrass management unit – the turf ecosystem • Develop reliable monitoring technuques, a critical component of any IPM program • Establish aesthetic thresholds • Evolve descriptive and predictive models of what pests are most likely to occur, when they should be expected to appear or become active, and the amount of damage that may take place • Develop an effective and economical turf management strategy

31. Management tactics • Genetic - breeding • Cultural – Uses fertilization, irrigation, site selection, plant selection and/or sanitation to prevent pest problems in the first place. Biological • uses beneficial organisms (insects, bacteria, etc.) to control pests. • Endophytes • Bt • Physical or mechanical – A preventive strategy. It includes screens or other barriers, temperature and humidity modification, traps, physical repellents and hand removal of weeds. • Chemical - pesticides

32. Management tactics • The most important thing you can do is to monitor and observe the management unit for weed, insect pest, and disease problems. • Close observations, assessment of pest and environmental problems, detailed record-keeping • Make sure that if you are going to do something that there is a definite need to do it.

33. Turfgrass Entomology

34. Cutworms • Black cutworm - Dark gray to black with a pale stripe down the back, but with few other distinguishing markings. • Bronze cutworm - Dark brown to black on the upper side of the body and paler on the underside. The upper surface has three narrow yellow stripes and a broad white-yellow stripe running down each side • Variegated cutworm - Grey to brown with an orange lateral stripe and a series of darker lateral markings. A row of yellow or white dots runs down the middle of the back

35. Black Cutworm • Adults (moths) migrate northward from southern states in early spring and deposit clusters of 10 to 20 eggs on grasses and weeds • Wind patterns (which affect the migration and ultimate distribution of the moths) and local environmental conditions strongly influence the severity of black cutworm infestations • As many as three generations per year

36. Bronze cutworm • Overwinter as eggs which hatch in early spring • Fully-grown larvae are present by late April and pupation occurs during mid-August • Single generation each year

37. Variegated cutworm • Overwinter as partially-grown larvae and resume feeding as grasses start to green up in the spring • Adults begin to appear in late spring and deposit up to 2000 eggs in clusters of 100 or more under the sheaths of grass blade • 2 to 4 generations of variegated cutworms each year

38. Cutworm Damage • Cutworms feed at night, cutting grass blades near the soil surface • Small circular dead or dying spots that increase in size to 1 to 2 inches in diameter as the worms mature • Occasionally cause severe damage on golf course greens (especially bentgrass) where they live and feed around the openings made by aerification

39. Determining if cutworms are present: • 1 tablespoon of 1% pyrethrins or 1/4 cup of lemon-scented household detergent in two gallons of water over one square yard of turf • Birds, and/or animals foraging in turf areas is often an indication of cutworms • Examination of cutworm or armyworm-infested turf will reveal clipped or skeletonized grass blades mingled with green fecal pellets

40. Control • Weather is warm and humid, fungal diseases sometimes infect the insects, reducing infestation levels • Parasitic flies and wasps lay their eggs on cutworm and larvae • Predation by birds • Chemical control: Perethrins, Marathon, Dylox, Dursban, Talstar,etc.

41. White Grubs • Immature stages of scarab beetles • White grub larvae are white and soft-bodied, with brown heads • Feed primarily on roots • 6 legs and the body is curved into a C-shape • Pupate underground, later emerging as beetles • Adults are heavy bodied, with widened front legs that are used for digging through the soil • Adults dig out of the soil, mate, burrow into the soil to lay their white eggs to repeat the cycle

42. Symtomology • In general, 10 to 12 grubs per square foot or more will eat enough roots to cause dieback of the turf • Turf will turn brown and can be easily turned back like a carpet • Various animals are attracted to white grubs for food (Raccoon, skunks, birds, armadillos) at levels as low as 3-5 grubs/sq.ft.

43. Determining if there is a problem • Scout at the proper time: late July/early August • Select areas known to have the problem in the past that are sunny, warm, and well-watered • You will have to dig to see the grubs • Quickly count the #, and replace sod • Determine if the numbers are high enough to treat

44. Control of white grubs • Chemical (insecticidal) • In general, mortality in excess of 60 percent is considered to be adequate for control • Insecticide longevity in the soil ranges from about a week to several months • Low persistence = quick kill, can be applied curatively • High persistence = longer kill (up to 3 weeks), should be applied when adults are laying eggs • Must be watered into the root zone (1/2” irrigation) • Diazinon, Merit, Dylox, Mach II, etc.

45. Control of white grubs • Cultural • Back off on irrigation in June and July (less attractive to egg laying adults) • Insecticidal nematodes • In years of high rainfall, there may be no need to treat as eggs will be spread over a large area, reducing threshold levels

46. Billbugs • Billbugs are weevils that attack turfgrasses and other crops • Frequently confused with white grubs • 2 most important: Bluegrass and hunting • Bluegrass billbug: cool season turfs • Hunting billbug: warm season turfs • Adult billbugs are poor fliers (localizes damage)

47. Billbugs (continued) • Larvae feed on roots • Adults feed on stems, stolons, and crowns (sawdust) • Overwinter as adults, about 1/4 inch long and blackish • Very hard shelled and have an elongated “snout” which houses chewing mouthparts • Adults are active on warm winter days and throughout the spring

48. Billbugs • Insert their eggs into stems and leaf sheaths • Larvae burrow in until too big then migrate to root zone (1/4 to ¾ in. in size) • Larvae can be found at any time of the year, although they are most common in June and July

49. Billbug control • Adult vs. grub stage control • Adults: foliar sprays (chlorpyrifos aka. Dursban) • Larvae: Usually controlled in June and July by soil drenches (just like other white grubs)