Category Archives: PLANT HOST

Plant Host categories

White rust on crucifers

Last week we received some turnip leaves into the lab with white patches on the undersides. After examining the leaves more closely under the dissecting and compound microscopes, we saw that the white patches were actually “rust” pustules containing sporangia. The pathogen, Albugo candida, which causes this disease, white rust, is actually not a true rust as it is not a member of the kingdom Fungi. However, the organism does imitate the true rusts in the manifestation of its reproductive structures as well as in the fact that… Read More →

Seen around College Station (Central TX).

Some patches in lawns caught my eye this week.  It was interesting to note that there were several lawns in my neighborhood had patch symptoms.  Most appear to be due to rhizoctonia blight (common name of disease = brown patch, yellow patch or large patch).  I just call it brown patch.  The “smoky” halo at the edge of the damage area of the turf was evident in many of them.  I have also been getting some reports from the Dallas-Fort Worth area that this disease (caused by the… Read More →

Root rot galore

A quick wrap of things seen in the last couple of weeks as temperature begin to get cooler.  At the Plant Clinic, we have some samples with root rot damage.  These are root rots of all kinds, occurring on woody ornamental and turf grasses.  Why is there a pickup in the incoming samples?  There is not an easy answer. It may be that since weather is getting cooler, more people are out in their yards -resulting in greater observations of the damage in the landscape.  Another explanation could… Read More →

Never stop learning

Earlier this month, I sent a couple of our Plant Clinic personnel to Florida with a group of AgriLife Extension county agents and specialists to tour some areas that has been affected by the disease, Citrus Greening.  This visit also allowed them to interact with researchers, extension personnel and growers in Florida, and also interact with our own AgriLife Extension county agents.  I charged both of them to submit a narrative report which is posted below with photos.  The ultimate purpose of this trip is the continuing education… Read More →

In our email box – live oak leaf drop….NOT

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 →