Texas Plant Disease Diagnostic Lab
Today is the start of the new school (2013/2014) year here. Texas A&M University students are back – new students are looking for their way around campus. The past few weeks has been extremely busy for all at the Plant Clinic with meetings to attend, samples to process and plant disease surveys to complete. I may tell you more about our summer activities in the future. You can always check out Clinic calendar to see what folks at the Plant Clinic are up to. Earlier this month, I… Read More →
About a week ago, I got an email in our PlantClinic box about live oak. The gentleman had read my blog post on the annual texas live oak leaf drop (March 2011). He had a very interesting question based on his observation of this tree. Below is the email he sent: After many years of watching my live oak trees lose their leaves every April – this year, one of them did not lose its leaves. Is this something to be concerned about? Was it last years drought… Read More →
Recently, I received an email via our PlantClinic email with a couple of photo wondering if the pea-sized “balls” on their Texas live oaks might be “fatal” to the trees. This is one of the few times that I get to give a happy reply. Those galls on the oak leaves are caused by insects… gall-making insects. This is quite typical on oaks in Texas. Rarely, do these galls ever kill an established tree. I say rarely, because I remember a situation about 8 years ago when we… Read More →
Blog article #4 by Marissa McCarthy (for partial fulfillment of BESC 484 requirement) Algal leaf spot is caused by the subcuticular leaf parasite from the genus Cephaleuros. This specific algal leaf spot is C. virescens and was sent into the lab on a magnolia from a private residence. Cephaleuros thrives in environments that are warm with high humidity, or poorly aerated soils. Characteristically this algae is harmless, causing only minor leaf spots on the upper surface of leafs that are raised, textured, orange to brown in color, with… Read More →
Blog article #3 by Marissa McCarthy (for partial fulfillment of BESC 484 requirement) Trabutia quercina is an ascomycete fungus that specifically targets species of oak trees, creating a disease commonly known as Tar spot on the leaves. The Tar spot was found on a live oak sample that was sent into the lab from a private residence. This fungus is characterized by the formation of black, blotchy lesions on the upper side of oak leaves, especially along the veins of the leaves. The lesions gradually expand and… Read More →
