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The waiting-bed (WB) system has the potential to significantly increase the length of the strawberry (Fragaria Xananassa Duch.) production season. In the WB phase of this system the plants were deblossomed and runners were removed to stimulate the production of a multiple crowned plant. The objective of this study was to examine the influence of planting date and cultivar on yield potential and vegetative growth of the strawberry plants in the WB and cropping beds (CB). Experiments were conducted in Ontario and Quebec. Early establishment of the WB favored the production of large multicrown plants. `Kent' appeared to be the best cultivar among five tested due to the many berries produced because of good fruit set. Yield potential was not realized in late-planted CB. The highest yields per plant (273 g) were obtained in Quebec with plants from the earliest WB. Yields in CB decreased with later plantings due to stress of transplanting when air and soil temperatures were high. Berry count was identified as the yield component most affected by the later planting date of the CB. The WB system has potential for season extension in strawberry, but WB must be established early in the season to encourage the development of a plant with high yield potential.

Nitrogen and carbohydrate content of roots and the onset of crown cold hardiness were compared in `Tristar' day-neutral (DN) strawberries (Fragaria × ananassa Duch.) that were given various fruit removal treatments. Nontreated `Hecker' DN and `Redcoat' Junebearer were also used to determine genotypic variation. The removal of fruit after 15 or 30 Sept. promoted the accumulation of starch and increased cold tolerance of crowns as compared to fruiting plants. Nitrogen was increased only when fruit was removed after 15 Sept. DN cultivars were less hardy than Junebearing cultivars, but `Tristar' was almost as hardy as `Redcoat'. When compared to `Redcoat', DN cultivars had a less abrupt temperature-kill profile, perhaps because they were multicrowned.

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A B S T R A C TThis paper summarizes the energy resource, the energy conversion technology, and the economic and social benefits of using wave energy technology. The Electric Power Research Institute (EPRI) estimates that the U.S. wave resource potential that could credibly be harnessed is about 6.5% of the 2004 U.S. national electricity energy demand (the total 2004 demand was about 4,000 TWh). Wave energy conversion (WEC) is an emerging technology; ten WEC devices have been tested to date in natural waters worldwide over the past 10 years. The economic opportunities are significant. A relatively minor investment by government in the public good today could stimulate a worldwide industry generating billions of dollars of economic output and employing thousands of people, while using an abundant and clean natural resource to meet our energy needs. Wave energy is potentially more easily assimilated into the grid (compared to wind and solar) because it may be more accurately predictable two to three days ahead and sold as firm power. Given proper care in siting, deployment, operations, maintenance and decommissioning, wave power promises to be one of the most environmentally benign electrical generation technologies. The primary barrier to the development and use of these technologies in the U.S. is the cumbersome regulatory process. We recommend and encourage the development of an effective regulatory system that fosters the application of this environmentally friendly electricity generation technology for our society.north and south. The power in the wave fronts varies in these areas between 30 and 70 kW/ m with peaks to 100kW/m in a few locations.EPRI estimates that the U.S. wave resource potential which could be credibly harnessed is about 6.5% of 2004 U.S. national electric-ity energy demand (EPRI WP-009-US). The U.S. wave energy potential is about 2,100 TWh/yr (see Figure 2) and composed of four (4) regional wave energy climates, each with their own characteristics. Assuming an extraction of 15% wave to mechanical energy (which includes the effects of device spacing, devices which absorb less than all the available wave energy and sea space constraints), typical power train efficiencies of 90% and a plant availability of 90%, electricity produced is about 260 TWh/yr, which is about equivalent to the total 2004 energy generation of conventional hydro power.In order to effectively use wave energy, the variability over several time scalesnamely: wave to wave (seconds), wave group to wave group (minutes), and sea state to sea state (hours to days)-must be understood. The time scale of seconds to minutes is important for continuously "tuning" the plant to changing sea states. The hours to days time scale is important for providing firm power guarantees into the day ahead electrical grid market. Being able to accurately forecast changes in wave energy in response to the FIGURE 1Worldwide Wave Resource (Thorpe, 1998). T Resource he power of ocean waves is truly awesome. Aside from thrilling surfing enthusiasts and e...