Question & Answers
These are the most common questions asked of Pinkston’s Turf Services. If you have a question that is not addressed in this section of our web page, please email your question to greenlawns@pinkstonsturf.com and we will get back to you as soon as possible.

Tree & Shrub Questions:

Question: Our photinia hedge is large and provides a privacy screen in the landscape. This makes the hedge very valuable to our property. The problem is that many of the leaves are covered with small, red spots. Some of the leaves are also falling off of the hedge. What is wrong with our photinia hedge?

Answer: The problem you have described with your Photinia hedge is a fungal leaf spot disease called Entomosporium leaf spot. This disease is all too common on Photinia plantings.
You can reduce the problem with regular applications of a labeled fungicide. You should also make sure that the foliage is not being kept wet by your sprinkler system or any other irrigation water source. Wet foliage on Photinia greatly increases the severity of this fungal disease.
We offer custom fungicide treatments for this fungal disease on Photinia.


Question: I have several, large, well-established, Austrian Pines in my landscape. Late this Summer one of the trees died within about a ten day period. The pine tree just turned brown and the needles are still attached. What could have happened to my pine tree?

Answer: Austrian pines are hard hit by a disease called Pine Wilt which kills pines rapidly as you have described. Other pines can also be affected, but Austrian and Scotch Pine have been the most severely affected by this devastating disease. The disease is actually spread by insects which carry a microscopic organism called a nematode from dead trees to healthy host trees. These nematodes then infect healthy pine trees causing rapid death.
There is no cure for this disease complex, but it is critical that you cut down and destroy infected pine trees as soon as possible to prevent the spread of this disease to healthy trees.
We have lost a great deal of our Austrian Pine population in the Tulsa area to this disease.


Question: I would like to know when to prune my azalea plants?

Answer: Azaleas bloom on last season’s growth, so the time to prune is right after they have finished blooming in Spring. Pruning later than this would remove the flower buds and eliminate any of those beautiful Spring flowers we all love.

Question: I have Euonymous in my front yard landscape beds. The leaves and some stems are covered by these tiny, white specks all over. What is this strange looking problem?

Answer: Euonymous is often attacked by these tiny, white insects which are called scale. The infestation can be suppressed by applying a properly timed dormant oil spray, as well as utilizing a labeled systemic insecticide. We have ornamental landscape plant care programs available to help with scale insects and many others.


Question: I have a large, beautiful Red Oak in my front lawn. This Spring there are these unusual , ball-like growths on the leaves and stems. What is this problem and will this kill my favorite tree?

Answer: Oaks are often affected by insect-induced galls which can be quite alarming. This may look unusual, but rarely does the gall problem ever result in the death of a tree. The galls are caused by tiny wasp-like insects before leaf growth actually is initiated. Dormant oil spray applications in late Winter can help alleviate insect-induced galls.


Question: I have a gorgeous Japanese Maple. Every August I have a problem with the leaves turning brown on the edges and falling. Is there a insect or disease causing this problem? What can I do to help ?

Answer: The browning leaf edges you describe are a text book example of marginal leaf scorching. Marginal leaf scorching is due to a lack of moisture. This is not the result of a insect or living disease organism. High temperatures in August and typically low amounts of natural rainfall make marginal leaf scorching very common on many trees, but even more prevalent on our heat sensitive maple species.
Careful and regular watering are critical to help reduce leaf scorching and defoliation during the hot, dry periods of the growing season. For the record, Japanese Maples need protection from the West sun to perform their very best.


Question: My azaleas have these clear-winged insects on the back sides of the leaves. What is this insect on my azaleas and how can I stop the pests?

Answer: The insects you have described are common pests of azaleas known as Lacebugs. These sucking insects can cause severe plant damage if not properly controlled. Apply a labeled, properly timed systemic-insecticide for best control. We offer custom control treatments for this pest problem.


Question: Can you tell me the difference between a webworm and a bagworm?

Answer: A webworm is actually a mass of leaf-feeding caterpillars which reside in a protective, silken web that occurs at or near the end of limbs or branches on trees. In contrast to that, a bagworm is found within a single, cone-shaped cocoon commonly attached to the foliage of evergreens.


Question: I love my Sweetgum tree, but I hate the spiny balls that it produces each year. Is there anything that I can do to stop the production of these seed balls?

Answer: A growth-regulator called Florel can be applied in Spring prior to the production of these seed balls. Timing is critical for effective control. Call us to schedule your treatment today.


Question: Our Crabapple trees have brownish, black spots on the foliage that are unsightly. What is this problem and how can we control it?

Answer: The problem you have described is commonly referred to as scab. Scab is a fungal disease common on Crabapples and Hawthornes. The brown colored spots actually almost become leathery or scab-like.