Scale Insects On Oleander

This appears to be scale insects (possibly Black Scale, but the photo does not provide enough detail for species ID), which are sap-sucking insects that, as adults, build a “shell” over themselves so that eggs can be laid protected under the adult body until they emerge as tiny little “crawlers” that will then eventually settle down to suck plant sap, build their own “shell” and continue the reproductive cycle. Scale insects in large numbers can be damaging to plants so you’ll want to get this ID confirmed by a local garden center, or some other professional source, and inquire about the appropriate control measures. We’ve included a link about scale and control measures from the UC Davis for your reference as well. http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7408.html