Apples


One way insects communicate with individuals of the same species is with pheromones. Pheromones are volatile chemicals released by an insect that usually can be detected only by individuals of the same species. There are a number of different types of pheromones, but the most common type is the sex pheromone. Usually the females will…Read more about Pheromones and Pheromone Traps[Read More]


Ascospore release is timed to optimize infection, which happens around tight cluster through petal fall. This is when all the fun really begins: Ascospores are at their peak and ejecting, and apple tissue is expanding, providing a larger, susceptible canopy that spores can hit. That excellent timing is the poetry of evolution in motion. Other…Read more about Ascospore release[Read More]


There has been some talk about the use of promalin to help overcome the damaging effects of freezing temperatures. Only a small amount of research has been conducted on this. Dr Steve McArtney showed that promalin applied after damaging freeze events could increase parthenocarpic (seedless) fruit development. Keep in mind this was only shown to…Read more about Frost Recovery Treatments[Read More]


What is the best way to assess bud damage from cold temperatures? Drs. Tara Baugher and Jim Schupp at Penn. State University have put together a nice page with some excellent photos explaining how to assess fruit bud survival: http://extension.psu.edu/plants/tree-fruit/news/2016/assessing-fruit-bud-survival-and-crop-potential I would add that unless you find that more than 90% of your buds have…Read more about Assessing Fruit Bud Survival and Crop Potential[Read More]


Frost and freeze damage was minor in small fruits and grapes. Below is a review of general guidelines for when we expect damage to buds, flowers and fruit. Developmental stage 10% kill (°F) 90% kill (°F) Apples Silver tip 15 2 Green tip 18 10 Half-inch green 23 15 Tight cluster 27 21 Pink 28…Read more about Frost and Freeze Damage Update[Read More]


A black swan refers to an event that defies expectation and that would be extremely difficult to predict. This spring is one of those. And although it seems unlikely that we will emerge from our last frost-free date (May 15 here in Tippecanoe County) unscathed, it could happen and then you could end up with…Read more about Lambs, Lions and Black Swans[Read More]


Page last modified: April 28, 2016

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