AboutJohn Cawly Expertise I can help with identification and possible treatment of plant diseases that affect houseplants and horticultural species, to include both biological (fungal, bacterial, viral, parasitic etc.) and environmental/cultural (watering, potting media, etc.) aspects.
Experience Practical experience with a wide variety of houseplants and greenhouse plants, including cacti, euphorbia, african violets, amaryllus, and many others.
Organizations American Phytopathology Society
American Society of Plant Biologists
American Society for Virology
Publications Molecular Plant Microbe Interactions
Proceedings of the National Academy of Science (in print)
Rhodora -- Journal of the New England Botanical Society
Allelopathy Journal
Education/Credentials BS, Southern Illinois University - Biological Sciences MS, Southern Illinois University -- Biological Sciences - Genetic Engineering Specialization PhD, University of Missouri Columbia -- Plant Microbiology and Pathology (Viral Diseases specialization/Biotechnology Emphasis)
Question My shrub in front of house is 4 feet tall...It started turning browm on one spot last year now it is spreading and there is white looking substance on the limbs....Someone said it could be Adelgid......Help Please.......Thanks.......Rodney
Answer Once thought to be aphids, adelgids are fluid-feeding insects that feed on coniferous species. The egg sacs of these insects look like the tips of cotton swabs clinging to the undersides of the branches. There are often more than one generation per season, and like aphids, are asexual which means that populations can grow tremendously large in a short period of time.
Without knowing the species, your location, and a detailed description of the symptoms, it is hard to provide anything other than background information. If you can provide photos it would be a great help. You can send them to me at:
jdcawly@mckendree.edu.
Typically, a single black lesion does not suggest an insect infestation. And if there are more like lesions this spring, that more likely is some fungal infestation.
