Question:
I have a red oak that has borers. I have been treating it each spring with a systemic insecticide for trees and shrubs as it was recommended by a licensed arborist. Last week I noticed new holes in a circle around the trunk about 10 feet above the ground. Sap is running down the trunk from the holes. My question is whether it would do any good to treat the tree right now or should I wait until spring?
Answer:
I would suspect that this is not borer damage but rather the result of a woodpecker like bird called a Yellow-bellied Sapsucker. It makes these holes to promote a source of sap and dines on this sap and on the insects attracted to the sap. Excessive hole drilling can infrequently cause limbs to die. However, most often no harm is done. Tree borers do not usually attack a healthy tree. You do not need to treat the tree.

Question:
Do mums freeze?
Answer:
Garden mum plants will survive any of the weather that we get in this area but the blossoms will have to be protected from frost or freezing weather.

Question:
I have many trees coming up through various shrubs. They are mostly mulberry, elm and hackberry. Some are 5 to 7ft. tall. Is there something I can put on the stump after I cut them out to keep them from coming back without harming everything else?
Answer:
Any of the herbicides containing Triclopyr such as Green Light Cut Vine & Stump Killer, Ortho Max Poison Ivy & Tough Brush Killer Concentrate or Bayer Advanced Brush Killer Plus will do the job. Just apply the concentrate to the cut surface of the trunk immediately after cutting. Take care not to get the herbicide on anything that you do not want to kill.

Question:
I have two firebush plants that look like they got killed from that first early frost. They were planted in July. Are they dead or can I cut them back?
Answer:
That light frost we just had, only killed the foliage. The plants are not dead. I recommend that you not cut them back at this time. However, they will need to be cut back to the ground early next spring before new growth commences around mid-February will be fine.

Question:
We all know that Texas Mountain Laurel (Sophora secundiflora) is a poisonous plant. What I would like to know is, if there are any dermal concerns. Is it safe to handle this plant and seeds? If it touches your skin for some length of time will it cause a rash?
Answer:
That depends entirely on the individual and his/her sensitivities. I would think that it would be unlikely and, know that it does not affect me in any way, but I cannot predict what it might do to you.

Question:
How do I get rid of and or kill lichen on my shrubs. I am starting to get some die back shrubs as a result. I do not want to lose my shrubs.
Answer:
The effect of lichens on a tree is only slightly detrimental. The plants are epiphytes. That is, they derive their nutrients from the air and not from the plant on which they are present on. The best control for lichens is to maintain the tree in good condition. Your die back problem is the result of something other than the lichens. Possibly drought related.

Question:
We recently purchased a home and would like to plant two crape myrtle trees in our open back yard which has plenty of sunshine. We have seen some trees in the past that have maroon blossoms and look more like trees than shrubs. Can you guide us to the variety that fits this description?
Answer:
Carl Whitcomb’s ‘Siren Red’ is the only “maroon” cultivar that I know. Visit with your favorite Independent Nursery and ask them to piggy-it-on to one of their spring California orders from Monrovia Nursery.

Question:
I recently acquired an Egyptian Fig from the Garden Volunteers of South Texas group, but they had run out of flyers that told about this new plant selection. Please help me find information on it.
Answer:
The Egyptian fig is a variety acquired from an Egyptian woman several years ago. It has large sweet fruit and is grown just as any fig would be grown in this area. For more information about growing figs, see: http://aggie-horticulture.tamu.edu/extension/homefruit/fig/fig.html.

Question:
A granulated herbicide, weed-killer, was spread out in the garden bed of my Vitex Tree. Its leaves have fallen off the tree and it almost looks like it is dead. Is the tree going to survive the herbicide? This herbicide was spread in all of my garden beds. My Knocks-Out roses also don’t look so good. Are they going to survive?
Answer:
Depending on the herbicide used, your plants could have been damaged or killed. Read the label on the bag that the herbicide came in and see what it says about using it around ornamentals. I cannot tell you whether or not the plants will live until they leaf at in the spring.

Question:
I intend to overseed my lawn. Do I need to aerate and dethatch the old lawn to reseed with winter rye or just aerate; and, do I need to mix the rye with a fescue blend?
Answer:
Since I don’t know what grass you are over seeding, I cannot give you much of an answer. The rye seeds need to be in contact with the ground in order to germinate. If you have to dethatch in order for that to happen, then it is recommended. I am assuming that your grass has gone dormant and you are doing this for winter color. The rye alone will give you that. A perennial selection of rye grass like ‘Pantera’ or Greyhound’ would be recommended at an application rate of one pound per 50-100 square feet. Typically, we would only overseed a healthy and established Bermuda lawn.

Question:
Are Bald Cyprus leaves good to use in your beds as mulch?
Answer:
Yes they are. A layer of 2 to 4 inches will be very beneficial.

Question:
I want to replace a dead tree with a Bradford pear (Pyrus calleryana). As I am 74 years old, I don’t want to plant a sapling, but rather a larger and therefore an older tree, but one that will provide robust growth. Could you please advise what age of Bradford tree I should be seeking to plant?
Answer:
I understand your concern about tree size. However, we have found that smaller trees will usually outperform larger ones. The Pyrus calleryana is, as are most fruit trees, a fast growing tree. I would recommend that you plant one that is growing in a 5 or 10 gallon nursery container.

Question:
How should I cut back an angel’s trumpet plant?
Answer:
When (if) the foliage has been damaged by freezing temperature or frost, you should cut the plant back to the ground. It will return in the spring from its roots.

Question:
I live on acreage south of San Antonio with sandy soil and very little rain in the summer. I need some very large, drought-tolerant shrubs to serve as a visual screen between our home and an eyesore down the street. They can’t be toxic as my neighbors have cows and they eat everything they can reach through the fences.
Answer:
I think that your best bet is the Arizona Cypress (Cupressus arizonica). These trees, once established, are very drought tolerant. They are used as wind breaks over much of West Texas where there is much less annual rainfall than here in South Texas. They will attain a height of 20 feet or more with a spread of at least 15 feet and are quite fast growing.

Question:
What is the best fertilizer for the Mountain Laurel? We have one that is three feet tall and has bloomed once, but with only sparse blossoms.
Answer:
The Texas Mountain Laurel (Sophora secundiflora) needs very little fertilization. Just spread a cup or two of any lawn fertilizer around the tree in the early spring and water it in good.