Critical irrigation threshold and cranberry yield components
Yield components are useful for characterizing the impact of crop management parameters on cranberry yield and are known to be influenced by irrigation management. This study was conducted to evaluate the potential contribution of cranberry yield components to maximizing yield, and the influence of the soil water tension threshold used to initiate irrigation (SWTI) on those components. During the 2011 and 2012 growing seasons, tensiometers were installed at three production sites in Quebec to test SWTI values ranging from 5.5 to 10.0kPa. Sites were cropped to cranberries to evaluate the impact of these irrigation treatments on yield components. The four most important cranberry yield components related to final yields were, in order of importance, the number of marketable berries per quadrat (BM/Q), the number of uprights per quadrat (U/Q), the number of marketable berries per upright (BM/U), and the marketable fruit set (BM/F). Significant reductions in BM/Q, BM/U and BM/F were observed when SWTI varied from 8.5 to 10.0kPa while a reduction in U/Q was associated with a SWTI of 5.5kPa. A SWTI ranging from 7.0 to 8.0kPa significantly improved the principal yield components.
Competition Among Berries on the Cranberry Upright

One hundred fruiting uprights were sampled for each of 3 cranberry (Vaccinium macrocarpon Ait.) cultivars, ‘Ben Lear’, ‘Bergman’, and ‘McFarlin’. Length of the upright, flowers per upright, berries per upright, seeds per berry, and weight of the berries were recorded. Two-dimensional partitioning using analysis of variance and multiple regression were combined for yield component analysis on a per-upright basis. In decreasing order, fruit set, berry enlargement, and number of flowers per centimeter of the upright were the most important components. Linear trends accounted for most of the differences due to position with lower positions having more flowers, fruit set, seeds per berry, and larger fruit than upper positions on the upright. More berries were set in ‘Ben Lear’ than in ‘McFarlin’ and ‘Bergman’.
Crop Losses Due to Weeds in Canada
Concerns about the effect of pesticides on our environment has stimulated questions about the direction of future research in weed science. Knowledge of crop losses due to weeds would be helpful in guiding research objectives by identifying areas of greatest need. A survey was conducted in 1991 to estimate losses due to weeds in 58 commodities in Canada. Data generated included: percent loss in production, quantity loss in production, and loss of production value (monetary value) for each commodity in each province. The estimated average annual losses caused by weeds in the 58 commodities were $984 million, with losses of $372 million in Eastern Canada and $612 million in Western Canada. In Eastern Canada, approximately 50% of the total loss occurred in hay crops and 33% in field crops, whereas in Western Canada, 84% of the total loss occurred in field crops. Loss of potential production due to weeds for each commodity is shown by province.