Use of Confined Dogs for Reducing Deer Damage to Apple Orchards

We assessed the efficacy of free-ranging dogs, confined by buried fences and electronic collars, for reducing deer damage to apple trees in three commercial apple orchards in Oswego County, New York State. During 1995 and 1996, we monitored paired dog-protected and control plots in each orchard. Within dog-protected areas, the percentage of damaged buds was lower, and fruit yield was higher in both 1995 and 1996 than for control plots. Gross economic returns were higher from dog-protected than control plots in both 1995 (by 51%) and 1996 (by 184%). After two seasons of growth, trees planted in May 1995 had nearly three times the cross-sectional area, and were 60% taller if they were in dog-protected rather than control plots. Dogs provided increased economic returns for growers at much lower cost than conventional barrier fencing.

EC28-36 Spraying Tree Fruits (Revised March 1932)

The production of sound, clean fruit is unquestionably one of the major problems facing the modern fruit grower. Culture may be neglected and pruning delayed for a time but the omission of sprays for even a single season demonstrates their absolute necessity. This applies equally to the commercial grower and to the farmer or gardener who has only a few trees. Spray materials, equipment, management, schedules, insect pests and orchard diseases are discussed in this 1928 extension circular.

Ribbon Cutting at Kimmel Education and Research Center

It is marvelously fitting that we gather here in Nebraska City on this lovely fall afternoon to officially celebrate this wonderful new center. Fall is a traditional-time of harvest in Nebraska, and for many of us there is a deep and abiding satisfaction in bringing a good crop to fruition. Apple harvests at Nebraska City orchards long have brought visitors here each year for fresh fruit and cider.

Model complexity affects transient population dynamics following a dispersal event: A case study with pea aphids

Stage-structured population models predict transient population dynamics if the population deviates from the stable stage distribution. Ecologists’ interest in transient dynamics is growing because populations regularly deviate from the stable stage distribution, which can lead to transient dynamics that differ significantly from the stable stage dynamics. Because the structure of a population matrix (i.e., the number of life-history stages) can influence the predicted scale of the deviation, we explored the effect of matrix size on predicted transient dynamics and the resulting amplification of population size. First, we experimentally measured the transition rates between the different life-history stages and the adult fecundity and survival of the aphid, Acythosiphon pisum. Second, we used these data to parameterize models with different numbers of stages. Third, we compared model predictions with empirically measured transient population growth following the introduction of a single adult aphid. We find that the models with the largest number of life-history stages predicted the largest transient population growth rates, but in all models there was a considerable discrepancy between predicted and empirically measured transient peaks and a dramatic underestimation of final population sizes. For instance, the mean population size after 20 days was 2394 aphids compared to the highest predicted population size of 531 aphids; the predicted asymptotic growth rate (λmax) was consistent with the experiments. Possible explanations for this discrepancy are discussed. Includes 4 supplemental files.