Mountain Date Palm (Phoenix loureiroi)

Pestalotiopsis is a group of fungi (now often placed in Neopestalotiopsis and related genera) that causes leaf spots and tip blight, especially on plants that are stressed or kept too wet. It shows up most after cool, rainy weather or in crowded plantings with poor airflow. Look for tan to dark-brown spots that may have a yellow edge, or shoot tips that brown and die back from the tip inward. Tiny black pinhead-like dots often appear in the dead tissue—these are the fungus’s spore-producing bodies. It commonly affects arborvitae, juniper, cypress, yew, boxwood, many palms (including indoor palms), and can also occur on strawberry leaves and fruit.

Root rot is a serious fungal disease that affects the root system of plants, causing them to decay and die. It is primarily caused by overwatering, poor drainage, or soil-borne fungi such as Pythium, Phytophthora, Rhizoctonia, and Fusarium. The disease thrives in waterlogged conditions where roots are deprived of oxygen, making them susceptible to fungal infection.

Scale insects are small sap-sucking pests that appear as brown, shell-like bumps on plant stems and leaves. There are over 25 species, divided into armored (hard) and unarmored (soft) scales. They feed by piercing plant tissue and extracting sap, which weakens the plant and can lead to yellowing, stunted growth, and even death if left untreated. They also excrete honeydew, which attracts ants and promotes sooty mold growth.

Spider mites are tiny arachnids (less than 1/20 inch long) related to spiders and ticks that feed on plant sap. They thrive in hot, dry conditions and can cause significant damage to ornamental and vegetable plants. During severe infestations, crop losses can reach 14% or higher as these pests disrupt vital plant processes including photosynthesis, carbon dioxide absorption, and transpiration.