Category Archives: ABIOTIC

Rapid Decline of Oaks

Ms. Sheila McBride (TPDDL diagnostician) and Dr. David Appel, Extension Plant Pathologist with the Texas A&M AgriLife Extension Service contributed this article to address the numerous inquires that has been received this year regarding declining oak trees -KO This year, beginning in the early spring to late summer, there has been many inquiries as to why the post oaks have “suddenly” died. The most frequent symptoms have been described as a rapid appearance of chlorotic (yellow) and/or necrotic (brown and dead) leaves throughout the entire crown. The leaves often… Read More →

Stress, fungal pathogen(s) or both?

Mid-September 2015 The last four weeks, I got at least 3 questions regarding why junipers or pines are dying.  Often the story is that there is one or two plants that are affected in amongst a bunch of trees.  Symptoms usually begins with several branches exhibiting die-back, gradually gets worse.Some narrative states that the plant appear to die quickly one the dieback started. SO what is going on….   I remember back in 2007… The scenario = 2005/2006 hard drought years and 2007 wet spring, mild temperature thru… Read More →

Why are the leaves falling?

In the past few weeks, I have been getting calls about poor looking and unhealthy oak trees… all kinds of oaks (mostly live, red and post).  In the last 7 days, I think I got at least 3 phone calls asking about post oaks loosing their leaves.  I hear panic and worry.  At home, I look to Mr. Tree.  Mr. Tree is our post oak (a name affectionately given by the wife to describe the tree to our youngling).  The home that we have is about 14 years… Read More →

New Year news – much activities and COLD

This year went off with a start where the Plant Clinic remains busy with many different activities.  Here are a few highlights: Many of you may have notice a new posting on our Facebook page called “Sample of the week”. This project/task is headed by our new Extension Assistant (newly graduated former student worker), B. Commer.  The goals is to post an interesting thing that is received by the TX Plant Clinic once every 1-2 weeks. Check out and like us on Facebook.  https://www.facebook.com/TXPlantClinic Thanks to colleague, Dr…. Read More →

Cladoptosis: An interesting phenomenon

Cladoptosis is a process in which trees shed their branches or “self-prune” as part of their normal physiology or in response to stress through the formation of an abcission layer at the branch base. Sources of stress which may contribute to this shedding include drought, soil and root compaction, or presence of disease. In the case of certain tree species, however, none of these factors need be present in order for Cladoptosis to occur. For some tree species, including larches, pines, poplars, willows, maples, walnut, ashes, bald cypress, and oaks,… Read More →