Thank you for the article, Henry. I had long suspected that RRD was less prolific in areas with very low humidity. I’m glad someone actually did an experient on humidity’s effect on the eriophyid mite. You see the big plantings of landscape roses in parts California with no signs of RRD. Here is Texas almost every one of them is grotesquely infested.

Interesting...makes me glad that I live in such a dry area. Thanks, Henry!