All hort articles about achieving, confirming or correcting for spray coverage.
This short article is a thought exercise designed to give some perspective on chemical rates, carrier volumes and the foliar area we expect them to protect. Imagine we are spraying the fungicide Captan on highbush blueberry. In Canada, the label rate is to apply 2kg/ha (28.5oz/ac) of planted area. Captan is 80% active ingredient, so […]
This article was co-authored by Kristy Grigg-McGuffin, OMAFA Horticulture IPM Specialist In view of the frequent heavy rains in many regions this season, understanding rainfastness, or the ability of a pesticide to withstand rainfall, is important to ensure proper efficacy. All pesticides require a certain amount of drying time between application and a rain event. […]
Read More… from Rainfastness of Insecticides and Fungicides on Fruit
When warm air is cooled, it loses some of its moisture-holding capabilities. This change often occurs at night, when plants (and other objects) cool. Once the temperature of the surface of the leaves, for example, drops below the dewpoint, it causes water to condense, forming the shiny dew that causes so many to question early […]
Some pesticide labels require or prohibit certain droplet sizes to reduce the potential for drift. But, even when labels are silent about size restrictions, operators should be aware of the potential for droplet size to affect coverage. In the case of airblast, droplets should be: Once spray leaves the nozzle, the operator has no more […]
Read More… from How Airblast Spray Droplets Behave (or Misbehave)
Assuming there are no mechanical or maintenance problems, water-sensitive paper can be used to diagnose sprayer performance. Go here to read more about water-sensitive paper. Interpreting the results and knowing what changes to make is the critical part of the process. Observing no coverage, or a sodden paper, make for obvious conclusions… but what about everything in between? Here […]