Turf Type Research Articles

Postemergence Control of Large Crabgrass (Digitaria sanguinalis) with Herbicides

Four field locations were used to compare environmental factors on efficacy of four postemergence grass herbicides in Kentucky bluegrass and bermudagrass turf. Imazaquin, BAS 514, and tridiphane were compared to fenoxaprop-ethyl, a registered herbicide, for postemergence control of large crabgrass. Best large crabgrass control was provided by BAS 514 and fenoxaprop-ethyl. Use of BAS 514 gave equal turf quality, phytotoxicity to the turf, large crabgrass control, and stand compared to fenoxaprop-ethyl. Imazaquin and tridiphane reduced turf quality and were phytotoxic to both turf types, and did not control large crabgrass adequately.

Adaptation and Differentiation of Golf Course Populations of Annual Bluegrass (Poa annua)

Morphological and physiological variation among annual bluegrass populations from the green, fairway, and rough were measured to determine the role annual bluegrass infestations outside the green play in maintaining the population in the green. Annual bluegrass populations from the fairway and the rough were similar to each other but differed from that of the green in habit, dry mass production, flowering, seed size, and germination. Seeds from each population established best in the type of turf from which they originated. It is concluded that, since few genotypes were common to the green and its surroundings, the populations in the fairway and rough played little or no role in maintaining the population of the green. The same is likely to be true wherever the management of greens and their surroundings differs sufficiently for marked population differentiation to occur. This finding does not preclude the possibility that some genotypes adapted to the green persist in the surroundings, and that these genotypes serve as sources of seeds for the colonization or reinfestation of annual bluegrass-free greens.

Research Note: Carotene and Xanthophyll Changes During Growth and Processing of Turf Bermudagrass

Experiments were conducted to determine the effect of drying method and grass-clipping length on the concentrations of carotene and xanthophyll in turf type bermudagrass (Cynodon dactylon). This lawn grass has potential for use as a xanthophyll source for poultry in the southern US.Oven-drying at 150 C for 40 min, oven-drying at 70 C for 20 h, dark room-drying at approximately 25 C for 120 h, and field-drying in natural sunlight were compared with freeze-drying. The field-drying method resulted in carotene and xanthophyll concentrations of only 15 and 52 mg/kg, whereas freeze-drying yielded the best values: 499 and 886 mg/kg, respectively. Regression analysis of both carotene and xanthophyll content indicated no significant differences that could be attributed to grass-clipping length.

Inheritance of Leaf‐Width and Seed Yield Characteristics of Lolium‐Festuca Hybrid Derivatives1

The appearance and acceptance of tall rescue for turf purposes maybe improved by reducing its leaf width. Flag leaf width was used as a criterion for improving turf texture of Lolium‐Festuchay brid derivatives. The objective of the study was to determine whether flag leaf width and concomitant fine texture characteristics of perennial ryegrass (Lolium perenne L.) ✕ tall fescue (Festuca arundinacea Schreb.) and {tall fescue ✕ giant rescue [F. gigantea (L.) Vill.]} ✕ [annual ryegrass (L. multiflorum Lam.) tall fescue hybridd derivatives were heritable. Parents (G0), first (G1), and second (G2) generation progenies were grown as spaced plants, seeded rows, and solid seeded sod plots, respectively. The fine‐leaf characteris genetically controlled having a different expression in competitive stands as compared to spaced plants or rows. Significant differences obtained among lines for leaf width indicated considerable genetic variability for the character. Nonsignificant line ✕ generation and line ✕ year interaction indicated that flag‐leaf width was not influenced greatly by management or environment. Regression of G2 polycross progenies on parents gave an estimated narrow sense heritability value of 0.70 indicating that a large fraction of the phenotypic differences between parents maybe recovered in the offspring. Leaf width of G2 polycross progenies was significantly less than that of widely used commercially available cultivars indicating that progress was made in improving turf texture of the population through breeding. A study of the genetic variability of seed yields of the hybrid derivatives showed that seed production compared favorably with tall rescue, that seed production was heritable, and that sufficient genetic variability exists for improving seed yield of the fine‐leaf turf types through breeding.

The place of amenity grass seed production.

In recent years the supply of seed of local types of fine turf grasses has decreased. This has resulted in the need for the importation of overseas cultivars of browntop, creeping bent grass and red fescue. These have generally proved to be very effective in producing high-quality turf. The coarser types of turf used in sportsfields for football and cricket are ideally ryegrass-dominant. Fine-leaved perennial ryegrasses have been developed overseas. and experimental plantings of these in New Zealand look very promising. Keywords: Amenity grass, New Zealand, Agrostis tenuis Lolium perenne, Agrostis palustris, Festuca rubra.

Drought Resistance of Kentucky Bluegrass Cultivars1

Abstract In a field test of 25 Kentucky bluegrass cultivars (Poa pratensis L.) “common types” were generally more drought tolerant than recently introduced turf types. ‘Code 95’, a common type, and ‘Merion’ exhibited high drought resistance and produced turf of good color, texture, and density. Turf mowed at 3.8 cm was more resistant to drought than turf maintained at 1.9 cm.

The effect of competition and salinity on the growth of a salt marsh plant species.

Young rhizome sprouts of the herbaceous perennial Jaumea carnosa were propagated from material collected in a salt marsh along the central California coast. The sprouts were transplanted to flats of sand sown with different densities of seeds of a representative glycophyte, Lolium perenne L. "Derby, turf type." Controls flats contained only Jaumea or Lolium. Three series of replicated flats were watered from above with dilutions of seawater in 1/10 strength Hoagland solution, such that dissolved salts were 400, 4000 or 11,600 ppm. Two other series were continuously subirrigated with 400 or 11,600 ppm salt water. After 61 days of treatment in a greenhouse with a 30/11°C thermoperiod (mean daily max/min), all plants were harvested and weighed. In the monospecific control flats, the growth of both species declined with increasing salinity, but the relative decline of Lolium was three times that of Jaumea. Jaumea's root: shoot ratio was also less affected by salinity. Both species grew well when subirrigated by 400 ppm salt water, but grew poorly when subirrigated by 11,600 ppm salt water, indicating that aeration alone is not the most significant factor in the marsh. The effect of interspecific competition on Jaumea was marked at low salinity, depressing growth by 52% compared to controls, but at high salinity the competitive effect was insignificant, whether the plants were watered from above or subirrigated. This supports the hypothesis that intolerant halophytes such as Jaumea are restricted in nature to salt marshes because they are poor competitors with glycophytes on non-saline soils.

Speed of Movement with Varying Footwear Conditions on Synthetic Turf and Natural Grass

Abstract The two-fold purpose of this study was (1) to compare subjects' movement times on synthetic turf with corresponding movement times on natural grass and (2) to determine the relative effects of three Footwear conditions on movement times recorded on the two playing surfaces. University male students (N = 44) served as subjects and were tested on each type of turf under each footwear condition. Results indicated that movement times were faster on synthetic turf, regardless of the footwear employed. The fastest movement times were exhibited by subjects wearing either tennis shoes or soccer style shoes while performing on synthetic turf. The use of football cleats on synthetic turf accounted for the next best level of movement time. A third level of movement time resulted from the use of either football cleats or soccer shoes on natural grass. The slowest movement times resulted from the use of tennis shoes on natural grass.

Japanese Beetle: Evidence of Resistance to Cyclodiene Insecticides In Larvae and Adults in Ohio123

Chlonlane, aldrin, dieldrin, and heptachlor have been used extensively to protect lawns, golf courses, and other types of turf in Ohio from injury by Japanese beetle, Popillia japonica Newman. Depending upon the rate, protection for 3 or more years could be obtained with these insecticides. Chlordane was used successfully to control Japanese beetle grubs in the fairways of the golf course at The College of Wooster (CW), Wooster, Ohio, for about 14 years. In 1970, infestations of grubs were noted in the fairways in spite of the applications. Beginning in the spring of 1970, the applications of chlordane (5–8 lb AI/acre) were increased to 1 each spring anti fall in an effort to control the grubs. However, samples taken May 25, 1972, from various fairways of the golf course showed that a larval population of 10–20/ft2 existed. The study reported here was conducted to determine whether the poor control achieved could he attributed to development of resistance to chlordane in the population.

Competition Between Established Tree Roots and Newly Seeded Kentucky Bluegrass1

AbstractLandscape situations frequently are such that trees may be well established when an attempt is made to establish turf. This occurs when renovating an old lawn, changing type of turf, or where new subdivisions are located in areas of established trees. This study was initiated to assess the effects of established silver maple (Acer saccharinum) and honey‐locust (Gleditsia triacanthos L.) roots on newly seeded Kentucky bluegrass (Poa pratensis). A connecting pot technique was used to maintain nearly uniform light intensity over tree‐shaded pots with or without tree roots.Silver maple and honeylocust roots established prior to seeding of common Kentucky bluegrass had a highly significant effect on growth of bluegrass, but the bluegrass had no significant effect on tree roots. Dry weight of foliage, sod and root yields, and root/sod ratios were reduced by presence of tree roots. Penetration of bluegrass roots into the main soil mass was restricted by silver maple roots. A mat of bluegrass roots about 0.95 cm (⅜ inch) thick was easily lifted from the soil containing tree roots.Established tree roots reduced the number of bluegrass plants established from seed, but had no effect on tiller production. It is hypothesized that biochemical inhibition (allelopathy) may be involved.

Effects of human activities on alpine tundra ecosystems in Rocky Mountain National Park, Colorado

The activities of summer visitors to the tundra of Trail Ridge in Rocky Mountain National Park results in the rapid destruction of vegetation in the areas seen by most visitors at close range—especially near parking areas. Ecosystems differ in their reaction to trampling; those with high soil-moisture are most easily damaged. Tall herb ecosystems are next, and then fellfield. Turf types are the most durable. Other activities affecting tundra are rock collecting, littering, crushing by car tyres, and flower picking.

Influence of Fungus Isolate and Grass Variety on Sclerotinia Dollarspot Development1

Four isolates of Sclerotinia homoeocarpa from various geographic areas of the Eastern U. S. were utilized in inoculation experiments on 37 Kentucky bluegrass (Poapratensis) varieties and experimental selections and with 18 varieties and experimental selections of creeping bentgrass (Agrostis palustris). The grasses exhibited a wide range of resistance and susceptibility to the four isolates of S. homoeocarpa. The isolate which was most virulent against bentgrasses was least virulent against the bluegrasses. When isolates were ranked in order of virulence against individual varieties, changes in rankings were noted from variety to variety. These changes in some instances were complete reversals with the most virulent for one variety becoming the least virulent with another. It was concluded that considerable pathogenic variation is present within S. homoeocarpa and that a wide range of grass plant response is present hi turf type blue‐ and bentgrasses.

Phenotypic and Genotypic Variation and Covariation of Some Quantitative Turf Characters of Poa pratensis L.1

Fifteen seed sources (accessions) of Kentucky bluegrass (Poa pratensis L.) constituting a rather broad based, random sample of bluegrass turf types, were grown to study several turf characteristics. Individual plants were transplanted into pots on two dates and ultimately space planted to the field.Measurements on six characteristics were made: (1) leaf width, (2) growth habit, (3) leaf angle, (4) rust resistance, (5) total spread and (6) sod spread. All characters were found to be highly significant for the accessions genetic mean square.Broad sense heritability and genetic coefficients of variation were calculated as estimates of the genetic variability among these accessions. Phenotypic and genotypic correlation coefficients were also computed, and indicated that simultaneous selection may be possible for important characters in the development of superior turf types.

Irrigation Water Requirements of Lawns

Irrigation water requirements for lawn grasses can be estimated by an empirical formula when adequate climatological data are available. The modified Blaney-Criddle formula can be used for this purpose. This procedure is explained and recommendations are made for the use of the results in accordance with the lawn condition desired. Most lawns can be subjected to drought conditions for short periods; if this is done, the irrigation water requirements can be materially reduced. An analysis of the available research data indicates that when the soil is near wilting point, light frequent irrigations at a rate of approximately one-half the normal consumptive use will maintain an appearance rated from fair to good. On certain types of turf, such a practice is allowable if not prolonged too long and if the turf is given good growing conditions at other times. Under these conditions it is believed that common lawn grasses seldom require irrigation to maintain appearance when the monthly net irrigation requirement is less than one-half the consumptive use computed for maintaining a full supply of moisture.