Turfgrasses have been utilized by humans to enhance their environment for more than I0 centuries. The complexity and comprehensiveness of these environmental benefits that improve our quality-of-life are just now being quantitatively documented through research. Turfgrass benefits may be divided into (i) functional, (ii) recreational, and (ill) thetic components. Specific functional benefits include: excellent soil erosion control and dust stabilization thereby protecting a vital soil resource; improved recharge and quality protection of groundwater, plus flood control; enhanced entrapment and biodegradation of synthetic organic compounds; soil improvement that includes COz conversion; accelerated restoration of disturbed soils; substantial urban heat dissipationtemperature moderation; reduced noise, glare, and visual pollution problems; decreased noxious pests and allergy-related pollens; safety in vehicle operation on roadsides and engine longevity on airfields; lowered fire hazard via open, green turfed firebreaks; and improved security of sensitive installations provided by high visibility zones. The recreational benefits include a low-cost surface for outdoor sport and leisure activities, enhanced physical health of participants, and a unique low-cost cushion against personal impact injuries. The aesthetic benefits include enhanced beauty and attractiveness; a complimentary relationship to the total landscape ecosystem of flowers, shrubs and trees; improved mental health with a positive therapeutic impact, social harmony and stability; improved work productivity; and an overall better quality-of-life, especially in densely populated urban areas.

Since water costs are projected to increase substantially, and water availability for turfgrass culture will become more limiting, there is a need for a detailed characterization of water use rates among turfgrass species. The evapotranspiration (ET) rates of 11 C‐4 warm‐season turfgrasses and one C‐3 cool‐season turfgrass were evaluated in minilysimeters with fritted clay as the rooting medium utilizing the water balance method. Turf plots of 1.5 × 1.5 m were constructed to ensure a natural environment surrounding each lysimeter. Evapotranspiration rates plus six morphological characteristics of each species were measured under nonlimiting soil moisture. Significant differences in ET rates were observed both among and within genera. ‘Texas Common’ buffalograss [Buchloe dactyloides (Nutt.) Engelm], ‘Georgia Common’ centipedegrass [Eremochloa ophiuroides (Munro.) Hack], ‘Arizona Common’ bermudagrass [Cynodon dactylon (L.) Pers.], ‘Tifgreen’ and ‘Tifway’ bermudagrasses [C. dactylon (L.) Pers. × C. transvaalensis Davy], and ‘Adalayd’ seashore paspalum (Paspalum vaginatum Sw.) had low ET rates; while ‘Emerald’ zoysiagrass (Zoysia japonica Steud. × Z. tenuifolia Willd. ex Trin.) was characterized as having a medium ET rate. ‘Texas Common’ St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze] and ‘Meyer’ zoysiagrass (Z. japonica Steud.) possessed medium low ET rates. However, a 1‐yr study showed that ‘Kentucky 31’ tall fescue (Festuca arundinacea Schreb.) and ‘Argentine’ bahiagrass (Paspalum notatum Flugg.) had medium ET rates, and ‘Common’ blue grama [Bouteloua gracilis (H.B.K.) Lag. ex Steud.] possessed a medium low ET rate. Those grasses with comparatively lower ET rates were generally characterized by (i) a high canopy resistance, including a high shoot density and relatively horizontal leaf orientation; and (ii) a low leaf area, including a slow vertical leaf extension rate and a narrow leaf texture.

The relative wear tolerance of seven cool‐season turfgrass species was determined for both sled (foot‐like) and wheel (vehicular) wear injury. Four methods of evaluating wear tolerance differentials were used: 1) visual rating of wear injury, 2) percent total cell wall content (TCW), 3) percent verdure, and 4) percent chlorophyll/unit area remaining after wear treatment. Manhattan perennial ryegrass (Lolium perenne L.) was most tolerant to wheel wear; Kentucky 31 tall fescue (Festuca arundinacea Schreb.) and Merion Kentucky bluegrass (Poa pratensis L.) ranked second; Pennlawn red fescue (F. rubra L.) and Italian ryegrass (L. multiflorum Lam.) were intermediate; while Cascade chewings fescue (F. rubra var. commutata Gaud.) and rough bluegrass (P. trivialis L.) ranked lowest. The relative ranking for sled wear was slightly different from that for the wheel. Visual ratings indicated that Manhattan, Kentucky 31, and Merion were equally tolerant to sled wear. However, Merion was the most wear tolerant to sled injury, according to ratings based on the percent verdure remaining after treatment. Manhattan and Kentucky 31 ranked second and third, respectively; while, Cascade chewings fescue and rough bluegrass were almost destroyed by the crushing, tearing action of the sled. Wear tolerance differentiation among species for the four methods tested was in high agreement. However, percent verdure remaining was the preferred method for quantitatively evaluating wear tolerance differentials. It eliminated arbitrary decisions that were inherent in the visual rating system, and involved fewer procedural steps than either the percent TCW or percent chlorophyll content determinations.

In these experiments, we tested in various in vivo assays the immune responses of inbred C3H/HeN(MTV-) (C3H-) mice during carcinogenesis by chronic exposure to UV irradiation. Although the UV-treated mice were unable to reject syngeneic UV-induced tumor transplants, they rejected H-2-incompatible tumor allografts and H-2-compatible skin allografts. The primary hemagglutinin response to sheep red blood cells was normal in these mice, as were the induction of a local graft-versus-host reaction with lymphoid cells from UV-irradiated donors and the induction of an inflammatory response to dimethyl sulfoxide in the footpads of UV-treated mice. An early transient depression of two reactions in UV-irradiated mice occurred: delayed hypersensitivity to dinitrochlorobenzene measured by footpad swelling and the graft-versus-host reaction in UV-irradiated recipients measured by the use of the popliteal lymph node weight gain assay. Both of these reactions returned to a normal level before the development of primary tumors. We conclude that the inability of UV-irradiated mice to reject syngeneic and autochthonous UV-induced tumors was not due to a generalized immunosuppressive effect of chronic UV irradiation.

This investigation was conducted to assess the relationship of cell wall constituents of seven cool‐season turfgrass species to wear tolerance. The turfgrass literature contains no data of this nature. The percent total cell wall (TCW), lignocellulose (ADF), cellulose, hemicellulose, and lignin were determined on a gram dry weight and mg/dm2 basis. Species differed significantly in cell wall constituents for both methods of determination. The relative ranking of the species based on the content of various cell wall constituents expressed on a gram dry weight basis was as follows: Cascade chewings fescue (Festuca rubra var. commutata Gaud) > Pennlawn red fescue (F. rubra L.) and Kentucky 31 tall fescue (F. arundinacea Schreb.) > Manhattan perennial ryegrass (Lolium perenne L.) > Merion Kentucky bluegrass (Poa pratensis L.) > Italian ryegrass (L. multiflorum Lam.) > rough bluegrass (P. trivialis L.). However, the species ranked as follows when the cell wall components were expressed on mg/dm2 basis: Kentucky 31 > Manhattan and Merion > Pennlawn and Italian ryegrass > Cascade > rought bluegrass. Cell wall constituents reported on a g/dry wt. basis were not correlated individually to wear tolerance. However, the combined effects of TCW, ADF, cellulose, and lignin accounted for 96% of the observed wear tolerance variation among the seven turfgrass species studied. TCW, ADF, cellulose, and hemicellulose contents expressed as mg/dm2 were significantly correlated individually to wear tolerance. Their combined effects accounted for 97% of the variation in inter‐species wear tolerance. Total cell wall content expressed on a mg/dm2 basis accounted for 98% of the variation in wear tolerance among the seven turfgrass species. Cell wall constituents were found to increase significantly with plant maturity, with the exception of hemicellulose. TCW increased significantly during the period from July to September, but declined in all species during October. The TCW, ADF, cellulose, hemicellulose, and lignin contents of leaf blades were significantly less than for the leaf sheath for all species.

Nine pregnancies in six patients with primary thrombocythaemia are reported. Eight pregnancies resulted in the delivery of normal infants. One pregnancy ended in spontaneous abortion at 7 weeks gestation. One pregnancy was complicated by superficial thrombophlebitis and a postpartum haemorrhage. We suggest that pregnancy in patients with primary thrombocythaemia can have a favourable outcome, but requires close monitoring. Administration of aspirin during pregnancy may be of benefit.

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W INTER injury of sports turf has recently become of increasing concern in the north central and northeastern United States. The basic components of these turf areas are common Kentucky bluegrass (Poa pratensis L.), annual bluegrass (Poa annua L.), and creeping bentgrass (Agrostrs palustris Huds.). They are usually maintained under conditions of close mowing, irrigation, and high fertility. In general, injury has been associated with an ice cover with annual bluegrass being the most susceptible species. The relationships between ice sheets and winter injury of bluegrass and bentgrass are not well defined. This study was undertaken to elucidate the effects of ice, snow, and water covers on the winter survival of bluegrass and bentgrass. REVIEW OF LITERATURE Very little work has been done on the factors involved in winter injury of turfgrasses, especially when associated with ice covers. Winter injury to plants in general was critically reviewed by Levitt (4) in 1956. Carroll and Welton (3) found that late season, heavy applications of nitrogen to Kentucky bluegrass turf resulted in decreased cold resistance. Later, Carroll (2) reported that the lethal soil temperature for Kentucky bluegrass and bentgrass was between-10° and-15° C. Also, species grown with high nitrogen were less resistant to cold than those with low.