Do you have yucca planted in your landscape? Have you checked it lately for pest problems? I know that it seems early to start checking for pests but I walked past the yucca at the office this week and it is covered with yucca plant bugs already.
Yucca plant bugs are in the order Hemiptera and are related to other sucking pests such as stink bugs and leaf-footed bugs, but are much smaller. Adult yucca plant bugs have a bright reddish-orange head and thorax with dark bluish-black wings. Immature yucca plant bugs (nymphs) look similar to adults but do not have fully developed wings. Since immatures do not have their wings fully developed, they're more red than black in color.
Both immatures and adults feed on plants by piercing plant tissue with their mouthparts causing yellowing spots on the foliage.
These little critters can sometimes be a challenge to manage since when you go to treat for them, they all dive into the center of the yucca into the nooks and crannies to hide. You can try products with active ingredients such as insecticidal soap, horticultural oil, azadirachtin (neem), pyrethrins or bifenthrin, cyfluthrin, or carbaryl. You will need to get good coverage to make sure that you get the pesticide to where the insects are hiding (and be careful not to get stabbed by the yucca!).