Successfully reported this slideshow.
Topdressing To Protect Bentgrass Greens In Winter An Iowa State study finds that fall topdressing treatments and nitrogen applications visibly improve spring recovery on two types of greens. Nick Christians Iowa State University Kern Diesburg Iowa State University Jeff Nus Kansas State University This is a view of two study areas covered in the following article shortly after treat- ment was applied. The modified soil is in the foreground, and the Nicollet soil is in the back. Darker plots have been treated with the 1:1:1 topdressing; light plots with the 7:1:2 topdressing; and the green plots are controls that received no topdressing. The green is the most expensive, periods of ice cover also can damage from desiccation where winter irrigationhighly maintained and delicate turfgrass greens. is not possible.area on the golf course. In the central In the central plains of the United Many techniques and materials haveand northern United States and through States and Canada, desiccation is been used to protect golf course greensmuch of Canada, winter is a particularly responsible for much of the winter from winter desiccation, including thedifficult time to maintain golf course damage on greens. These regions often use of protective blankets, polyethylenegreens. These areas are susceptible to have extended periods in the winter films, wood and synthetic fibers,a variety of forms of winter damage, months with no snow cover and little branches and other debris, fences toincluding cool temperature diseases, moisture from rain. They also are hold snow cover and a soil topdressingdirect low temperature kill, desiccation, known for winter and spring winds that layer. Each technique has been usedtraffic and frost heaving. Extended dry the turf, causing extensive damage Continued on p. 6866 Golf Course Management I September 1987
applications on the spring recovery of Fertilizer treatments were appliedTOPDRESSING from p. 66 these two types of greens. after top growth had ceased, between Two adjacent experimental greens Nov. 10 and Nov. 18 in 1980, 1981, that had been established with Penn- 1982 and 1983. Topdressing treat-with success, but each has its problems, cross in September 1979 were used in ments were applied immediately afterincluding in some instances high the study. One area was formed of a the fertilizer was applied. The areas Nicollet soil with a pH of 6.5. The received no supplementary irrigation second green was composed of a during the winter and early spring. Each A high degree of managerial "modified" soil that had been con- of the treatments was repeated three skill and knowledge is structed of one part sand, one part times on each of the two greens. required for use of any Nicollet soil and one part peat. The pH Data collection began each year in was 7.9. Physical tests performed on the spring with the first sign of green of these methods. this soil before the initiation of treat- color in any of the plot areas and con- ments showed that this soil contained tinued until all plots showed complete 4.6 percent gravel, 62.3 percent sand, recovery from winter dormancy. Thematerial costs - and, with polyethylene 21.3 percent silt and 11.8 percent clay. data collected was designated springfilms and other synthetic materials, an The bentgrass was maintained at a recovery, which was based on color,increase in cool temperature diseases. 1/4-inch mowing height. The area was density and uniformity (the lack ofA high degree of managerial skill and fertilized during the season with liquid winter damage), and rated on a scaleknowledge is required for the use of any urea solutions at a rate of 0.2 lb. of 1 to 9, with 1 equaling no sign ofof these methods. Nl1,000 square feet whenever the recovery and 9 equaling total recovery. The use of other cultural practices bentgrass showed signs of nitrogen defi-with winter protection techniques has Varying Weather Conditions ciency. Insecticides and fungicides werenot been fully investigated. For exam- Weather conditions during the four used as needed during the season.ple, the use of dormant fertilizer appli- winters of the study varied greatly. The Three main treatments were includedcations may be useful with some of the 1980-81 winter was mild, with very little in the study. The first was a controltechniques, although this practice where no topdressing was applied; thewould not be recommended with poly- second consisted of a 7: 1: 2 The 1981-82 season wasethylene films and other methods that (sand:soil:peat mixed on a volumeresult in temperature increases and late basis) topdressing applied at 0.77 cu. the opposite extreme,winter growth. with very cold temperatures yd./1,000 square feet (0.23 inchIowa State Experiment depth) to the surface of the green; and and heavy snow cover. In a four-year study at Iowa State the third included a 1: 1: 1University, combinations of nitrogen (sand:soil:peat) applied at the same ratefertilizer and two types of soil topdress- in the same way. snowfall or snow cover and monthlying were applied to Penncross creeping Each topdressing plot measured 10 mean maximum temperatures thatbentgrass greens that had been estab- feet by 10 feet. The topdressing plots ranged above freezing. The 1981-82lished on both a native Iowa soil and a were further divided into three nitrogen season was the opposite extreme, withsoil modified with peat and sand. The treatments that included.a control, 0.5, very cold temperatures and heavy snowobjective was to observe the effects of and lib. Nl1,000 square feet applied cover. The 1982-83 winter began mildfall topdressing and late-fall nitrogen in the form of gran ular urea. Continued on p. 70 The effects of topdressing treatments and fertilizer treat- Monthly mean temperatures, snowfall and snow cover on the ments on spring recovery of Penncross creeping bentgrass. study area for 1980-84(0 degree centigrade; equals freezlrlg, and 2.54 em equals 1 inch).;68 Golf Course Management / September 1987
the greater moisture- and nutrient- The visible effects of topdressing wereTOPDRESSING from p. 68 holding capacity of the Nicollet soil. The apparent each year, but particularly in earliest date of spring green-up and the years following mild winters. The visi-C!nd ended with heavy snow, whereas duration of treatment differences did ble effects of fertilization were morethe 1983-84 season began with very not vary between the two soils, subtle .cold temperatures and heavy snow but however. . The application of topdressing toended with rather mild temperatures bentgrass greens at a rate of 0.77 cu.and a period in February with no snow The effects of topdressing were yd./l,OOO square feet after growth hascover. greatest following the open, mild ceased in the fall may have a beneficial Topdressing treatments improved winters of 1980-81 and 1982-83. The effect on spring recovery, particularlyspring recovery in each of the testing least benefit from these treatments was during mild winters with little snowfall,years. However, the first date of visible observed after the extended snow cover regardless of whether the topdressinggreen-up and the amount of time from and cold temperatures of 1981-82. has a high sand content. Spring recov-first green-up to the time when no Neither topdressing material was con- ery can be further enhanced by the ap- sistently better than the other on either plication of nitrogen fertilizer at rates up soil type, although there was a slight ad- to 1 lb. N/l,OOO square feet to the The effects of topdressing vantage to the 1: 1: 1 topdressing in the greens surface before topdressing ap- springs of 1983 and 1984 on the modi- plication. were greatest following fied soil and the springs of 1981 and the mild winters of 1984 on the Nicollet soil. The ratings Although topdressing and fertilization 1980-81 and 1982-83. for the 7: 1: 2 topdressing exceeded treatments did not increase cool- those of the 1: 1: 1 only in the spring of temperature disease infestations on this 1982 on the Nicollet soil. It had been area and likely would not on most opendifferences could be observed among expected that the darker-colored 1: 1: 1 areas in the Midwest, caution should betreatments varied with the year. In topdressing would be consistently su- used with these treatments without thespring 1981, treatment differences were perior to the 7: 1: 2, but this was not the use of fungicides in more protectedobserved for 31 days, followed by 22 case. areas or in areas where there has beendays in spring 1982, 51 days in spring Effects Of Fertilization a history of cool-temperature diseases.1983 and 15 days in spring 1984. The There was an increase in spring The extent to which topdressingvery short duration in 1982 can be recovery with increasing fertilizer rates treatments can improve spring recoveryattributed to the extended snow cover on both soils in each year, with the ex- will likely be surprising. If the methodinto April. The extended period of 1983 ception of spring 1982. At no time did is being used for the first time, a smallwas due to the lack of snow cover and the application of urea have a detrimen- untreated area should be retained sowarm temperatures in February fol- tal effect on the bentgrass. Even when that the real effects can be observed.lowed by heavy snows in March and late-season snow covered plots that hadApril. begun to recover in 1982, 1983 and Bibliography The spring recovery ratings for the 1984, no signs of cool-temperature dis- 1. BEARD, J.B. (1964a) Effectsof ice, snow and watercreeping bentgrass on the Nicollet soil eases were observed on any of the covers on Kentucky bluegrass,annual bluegrassandwere generally higher than for equiva- treated areas, even though no winter creeping bentgrass. Crop Sci. 4:638.lent treatments on the modified soil. fungicide applications were made after 2. BEARD, J.B. (1964b) Causal agents in winter inju- ry of turfgrass and their relative importance. Agron.These higher ratings are likely due to the 1981 season. Abstr. p. 99. 3. BEARD, J.B. (1966) Direct low temperature injury of nineteen turfgrasses.Mich. Agric. Exp. Stn. Bull. 48(3):377. 4. BEARD, J.B. (1969) Covers for the protection of turfgrasses against winter desiccation and low tem- perature injury. Agron. Abstr. p. 52. 5. BEARD, J.B. (1973) Turfgrass: science and culture. Prentice-Hall, Englewood Cliffs, NJ. 6. BEARD, J.B. (1982) Turf Management for Golf Courses. Burgess, Minneapolis, MN. pp. 452-458. 7. LEDEBOER, F.B. and SKOGLEY, C.R. (1967) Plastic screens for winter protection. Golf Superin- tendent. 35(8) :22-23. 8. WATSON, J.R., KROLL, H., and WICKLUND, L. (1960) Protecting golf greens againstwinter kill. Golf Course Rep. 28: 10-16. 9. WATSON, JR., and WICKLUND, L. (1962) Plas- tic covers protect greens from winter damage. Golf Course Rep. 30:30-38. 10. WATSON, J.R. (1964) Methods of minimizing winter damage. Agron. Abstr. p. 103. 11. WATSON, J.R. (1968) Blankets to protect gol1 greens against winter injury. Agron Abstr. p. 61. 12. WATSON, J.R. (1968) Prevention and control of Spring recovery of Penncross creeping bentgrass greens with and without desiccation on golf greens. In: Proc. of the First Int. topdressing in Apri/1981. Plots showing no recovery are untreated controls. Turfgrass Res. Con/., Sports Turf Res. Inst., Bin- gley, England, pp. 301-305.70 Calf Course Management I September 1987