Scale Insects

You are correct. We can’t see clearly what the species the scale is, but it is some kind of scale insect. These insects don’t usually cause major problems to plant health unless their population is very large. However, if you don’t control them, and the conditions are right for their reproduction, they can get out of control. Keep your plant healthy and it will be better able to withstand the insect feeding. Control for scales varies by species or type of scale. We’ve included a link for your reference in controlling them outdoors, but if this is a house-plant and the population is not large right now, we suggest you use a dilute solution of rubbing alcohol and water on a damp cloth and wipe the scales off of the leaf and stems (if they are also feeding there). Don’t over-do the alcohol as you can cause damage to the protective leaf cuticle with too high a concentration. You can also give the plant(s) a shower, literally, to clean off the sticky “honeydew” exudate. Keep an eye out and continue to remove developing scales. Otherwise, if the population numbers are high you can use pesticidal products, but they may not be very effective on the adult (covered) stage of the scale (they will work on the younger crawler stage if applied correctly). We recommend you use horticultural oils whenever possible (you’ll want to apply outdoors, but keep the plant in a shady location and make sure its watered a few hours before applying the oil to avoid burning the plant tissues)
For outdoor plants: http://www.ipm.ucdavis.edu/QT/scalescard.html