Manna Ash (Fraxinus ornus) Care Guide

Canker is a disease caused by various fungi and bacteria that create necrotic, sunken areas on bark of branches, stems, and trunks. Pathogens enter through wounds and natural openings, especially when plants are stressed. Canker can gradually weaken or kill branches by disrupting water and nutrient flow.

Rust is a common fungal disease caused by fungi in the order Pucciniales that affects a wide variety of plants. The disease gets its name from the characteristic orange, yellow, or reddish-brown pustules that appear on leaves, resembling metal rust. This obligate fungal parasite requires living plants to survive and can cause significant economic losses in agricultural crops.

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.

Leafminers are the larvae of various insects including flies, moths, sawflies, and beetles that tunnel between leaf surfaces, creating distinctive serpentine trails or blotchy patches. While primarily cosmetic, severe infestations can weaken plants by reducing photosynthesis capacity and making them susceptible to secondary infections.

Aphids are small, soft-bodied, pear-shaped insects (1/16 to 1/8 inch long) that feed by sucking nutrient-rich sap from plants. They reproduce rapidly and can quickly weaken plants, causing distorted growth and transmitting plant viruses. Aphids come in various colors including green, black, red, yellow, brown, and gray. They secrete honeydew, a sticky substance that attracts ants and encourages sooty mold growth.