‘Gloom’ and doom when these insects are on hot, dry red maple trees.
This is because the arthropods feed and thrive on them, especially in warm and dry urban landscapes, a University of Florida Institute of Food and Agricultural Sciences researcher says.
Dale’s new research is important as residents and urban landscapers decide when and where to plant red maple trees, which are native and widely distributed in North America from Florida to Canada and whose canopy helps cool urban areas.
He wanted to know how the gloomy scale, an insect widely distributed around the eastern and southeastern U.S., would respond to hot, dry weather – conditions typical for urban trees.
Researchers studied urban red maple trees at various temperatures around the city.
At the end of 2015, they collected gloomy scales from each tree, measured their body size, dissected them and counted the number of eggs the insects produced, Dale said.
They then looked at the relationship between the temperature in the tree’s canopy and whether the tree was irrigated.
Scientists wanted to see if either factor had an effect on the insects’ body size or egg production.
The hotter and drier the trees were, the more eggs the gloomy scales produced.
Since the gloomy scale benefits from warming and drought — two features common to urban landscapes — and urban landscapes are rapidly expanding, there is a potential for this pest to proliferate and cause even more problems in the future.” Urban foresters and landscape architects can use the study’s findings by selecting more appropriate trees to be planted where heat and drought stress may be likely, Dale said.