Many Eastern Red Cedar (Juniperus virginiana) trees in the area are 
getting covered with masses of orange goo-like stuff - kind of looks like something from outer space splattered over the trees. Actually, I've never seen it quite this heavy and widespread before. What "it" is is a fungus, called cedar-quince rust (Gymnosporangium clavipes). This is an interesting fungal organism that requires 2 different hosts to complete its life cycle. One stage occurs on junipers - in this case, the common eastern red cedar. There are actually several different rust fungi, and some look a lot alike.
This orange mass of goo will eventually dry, and release gazillions of spores, many of which will land on some host in the Rosaceae family, like apples, flowering quince, mayhaws, pears, hawthorn, photinia, or crabapples. There they will infect the young foliage, causing yellowing, spotting and possibly heavy defoliation if the conditions are just right. Young developing fruit might also become affected, resulting in odd projections covering the fruit.
Dr. Kevin Ong, Plant Pathologist with Texas AgriLife Extension Service, has written a short article on a related species, cedar-apple rust. You can read it here.
getting covered with masses of orange goo-like stuff - kind of looks like something from outer space splattered over the trees. Actually, I've never seen it quite this heavy and widespread before. What "it" is is a fungus, called cedar-quince rust (Gymnosporangium clavipes). This is an interesting fungal organism that requires 2 different hosts to complete its life cycle. One stage occurs on junipers - in this case, the common eastern red cedar. There are actually several different rust fungi, and some look a lot alike.This orange mass of goo will eventually dry, and release gazillions of spores, many of which will land on some host in the Rosaceae family, like apples, flowering quince, mayhaws, pears, hawthorn, photinia, or crabapples. There they will infect the young foliage, causing yellowing, spotting and possibly heavy defoliation if the conditions are just right. Young developing fruit might also become affected, resulting in odd projections covering the fruit.
Dr. Kevin Ong, Plant Pathologist with Texas AgriLife Extension Service, has written a short article on a related species, cedar-apple rust. You can read it here.
