Last night and tonight there are freeze alerts posted by the Weather Service. Who exactly would believe that you needed to be concerned about a “freeze” in almost the middle of May? We are not talking frost here, we are talking freeze. The difference? A frost advisory is issued when the predicted temperature is expected to fall to 36 degrees or lower in the following 3 to 30 hours during a growing season. A freeze warning is issued when there is an 80% or greater chance that the temperatures are expected to fall to 32 degrees or lower in the ensuing 3 to 30 hours during a growing season. If the temperature is expected to fall below 28 degrees this is referred to as a hard freeze. The concern right now, is mostly for the fruit trees and bushes that are blooming. Fruit blossoms are very vulnerable to freeze damage. As a result, Temperatures below 32 just before the flower opens can injure the ovules and prevent fruit set. Pollen grains will generally not germinate at temperatures below 41, and if temperatures fall below 51, the pollen tube may not grow, and fertilization may not occur even if pollination occurred. This can be devastating for the fruit farmers because damage to blossoms now means no fruit later.  Cutting through buds let farmers know if the buds have suffered freeze damage. Buds with black or brown all the way through will not produce fruit. Farmers and the Department of Agriculture are assessing to determine what, if any freeze damage will have on this year’s apple and fruit crops.

Reblog this post [with Zemanta]
Advertisements