Plum leaf curl
I just saw that on my Pluot tree. The tree is in full bloom can I spray or cut affected areas off. What is a good spray during bloom?
Santa Clara County California plum trees
Thank you for your question. Unfortunately, you missed the window (November through dormancy) when applications of insecticides will not also kill any pollinating insects, including bees. You undoubtedly know that pollinator populations are in great jeopardy because of the use of insecticides during their active pollinating times. Here is an article about the control of the aphids that cause the leaf curl: http://ipm.ucanr.edu/PMG/r611301811.html
Having insects that eat (predate on) the aphid is a biological control that does not harm pollinators. Even the organic need oil will kill pollinators on which it lands.
Note that many of the chemicals mentioned are not available to home orchardists. I suggest you contact your county Extension office (http://cesantaclara.ucanr.edu/Programs/contact/) for other suggestions. Good luck!