Research trials, conducted from 1991 to 1998, evaluated early blight forecasting systems for use in fresh-market tomato (Lycopersicon esculentum) production in northern New Jersey. Initial trials focused on determining which of three forecast systems—NJ-FAST, CU-FAST, TOM-CAST—would optimize fungicide use. The TOM-CAST system generated fungicide application schedules that reduced foliar disease rating compared to the untreated check and, in 1 year, controlled diseases as well as a weekly schedule with 3 rather than 14 applications. TOM-CAST was easier to use than NJ-FAST or CU-FAST because it required fewer weather data inputs and simpler forecast calculations. Subsequent trials evaluated and defined thresholds for using TOM-CAST in northern New Jersey and evaluated the efficacy of several fungicides with TOM-CAST. Of the six TOM-CAST modifications evaluated, TOM-CAST beginning fungicide applications at 25 cumulative dew severity values (dew SV) and reapplying fungicide at 15 or 25 cumulative dew SV reduced disease rating as much as a weekly schedule in 1995 and 1996 and with fewer applications. After 5 years of trials, decision thresholds for using TOM-CAST in northern New Jersey were chosen and this new version of the forecast system designated NJ-TOM-CAST. It was verified in 1997 and 1998 and shown to generate fungicide application schedules that reduced foliar disease rating compared to the untreated check in both years and as much as the weekly schedule in one year. From 1995 through 1998, the conservative TOM-CAST schedules, TOM-CAST 25-15 or NJ-TOM-CAST, required on average 6 fungicide applications per year compared to weekly schedules that required on average 15 applications per year. In 1996, marketable yield was increased with TOM-CAST scheduled treatment compared to the untreated check and was the same as or greater than yield with weekly treatment. In the other 3 years, fungicide applications, whether applied on a calendar-based or TOM-CAST-based schedule, did not increase marketable yields compared to the untreated check. Fungicides shown to be effective when used with NJ-TOM-CAST schedules included both low cost and new chemistry materials. Copper fungicides, some of which are allowed in organic crop production, did not consistently control fungal diseases when applied on the NJ-TOM-CAST schedule. Applying fungicides on the NJ-TOM-CAST schedule instead of calendar-based schedules did not increase bacterial disease severity. Powdery mildew damage was more severe with NJ-TOM-CAST-scheduled applications than weekly applications in 1 year, affirming the importance of disease monitoring in the field when using NJ-TOM-CAST. By 2000, through a cooperative effort of Rutgers Cooperative Extension and SkyBit, Inc. (Boalsburg, Pa.), a commercial weather service, NJ-TOM-CAST was available to northern New Jersey tomato growers by subscription.

I N 1949 a colony was started in Ottawa from 16 Greenland Varying Lemming, Dicrostonyx groenlandicus groenlandicus, which had been captured at Igloolik on 14 September 1949 (see Manning, 1950). Three females and 3 males bred, and the colony reached a peak of 76 in April 1951, but declined during the following summer. A single female Mackenzie Varying Lemming, D. g. kilangmiutak, from Tuktoyaktuk, was added to the colony that fall, and mated with one of the D. g. groenlandicus males to produce six litters, after

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Morphometric variation in 21 characters of 470 skulls of Lepus arcticus from Canada and Greenland was analysed statistically. Geographic trends in variation were assessed separately in Canada and Greenland using composite samples derived from groupings of geographically contiguous localities. For most characters, univariate analyses revealed clines of decreasing size from the polar regions southwards, though jugal maxillary ridge width exhibited a reverse cline and maxilla orbital process width varied irregularly among samples. Discriminant analysis synthesized these trends such that the phenetic positions of the samples in discriminant space were approximately congruent with their geographic positions. The smoothness of the cline is interrupted between the Queen Elizabeth Islands and the islands of the lower Arctic Archipelago and is not paralleled by similar sharp environmental transitions. Gene flow across the water gap therefore seems to be very restricted. Discontinuities among the Greenland samples can be attributed partly to sampling or distributional hiatuses, but infraspecific differentiation appears to be occurring on either side of the Melville Bay glacial barrier. Statistically significant multiple regressions of factor scores of climatic variables on factor scores of skull morphology suggest thermoregulatory adaptation as a result of selection for increased skull size in colder climates, as is subsumed by Bergmann's rule.