QUESTION: Three days ago I noticed a blue, sticky, speckled residue on the top-side of some hibiscus leaves. I rinsed them off with soapy water. The next day the stuff was back, but had spread to other hibiscus. Yesterday, I sprayed with Ortho Systemic. Today, it is back on the original plants and has spread to an azalea and some begonias. I inspected for aphids, but found none. There appears to be some white specks intermingled with the residue, that may or may not be insects. When I shake the limbs, there is no swarming like you see with white flies. Would you please help to identify the problem?

ANSWER: My best guess is aphids or mealybugs. Normally these insects produce water soluble, sticky residues that cover leaves--though the blue color is a puzzler. For insects, look up into the plant at the undersides of leaves. The sticky residue drops down from insects feeding above the affected leaves. This sometimes happens from canopy plants above the affected ones. Aphids are not hard to spot, once they are feeding on is located. Look for small, pear-shaped greenish, yellow or brown insects clustered along plant stems, buds, and under leaves. Orthene usually works, as would Malathion, insecticidal soap and horticultural oil.

I hope this helps. For more information about aphid control see
http://insects.tamu.edu/extension/bulletins/uc/uc-031.html

<<<<<<<<<<<<<<<<<<<<<<<<
Michael Merchant
Extension Urban Entomologist
Texas A&M Research and Extension Center
Dallas, TX 75252-6599

QUESTION: I am doing some research on landscaping trees because my wife and I are going to be planting some trees at our new house this fall. I want to plant my trees as close as possible to my house for shade. The house faces southeast and I need as much shade as I can get, especially in the NW-facing rear of the house. My question is: How close can I plant trees to the foundation of my house? I will probably be using mostly oak trees--either live oak, red oak, bur oak or maybe Chinkapin. We have a 2-acre lot so space is not a concern.

ANSWER: The key to your shade problem is not so much to plant the trees close to the house, but rather to grow the trees fast. Try to stay at least 15 feet from the house with the trees --- 20 to 30 feet would be better. The trees you have selected will grow to be big trees and so they will do better if they have a lot of room. The trees should be at least 35 feet from each other. In this way they will not compete with one another for water and nutrients and will also develop a full sized canopy.

The key to making the trees grow will be excellent weed control, water and fertilizer. You need to keep the weeds and grass, including flowers, away from the dripline of the tree and out about another foot for the first 3 to 4 years of the life of the tree. In this way the tree has no competition and will get all of the water and nutrients. Fertilize the trees 4 times a year; March, April, May and June with ammonium sulfate. Use about a cup per tree the first year. After that use one pound per inch of trunk diameter. So if the tree has a two inch trunk, the tree would get 2 pounds of ammonium sulfate. Put one quarter of the two pounds or ½ pound on in March, the next in April and so on. Also keep the trees well watered and before you know it you will have lots of shade.

QUESTION: About 7 years ago my husband and I were eating grapefruits and as a joke he put a single grapefruit seed in a planter that had housed a palm tree which had died. Well, a few months later something sprouted and continued to grow......It is now about two feet high and has a small leaf attached to a larger leaf on the stem and also has some serious thorns. Do we have a grapefruit tree?

ANSWER: Yes, you do!!!! The tree has thorns because it is in a juvenile state. Once the tree matures and starts to flower, it will not have thorns. However, if the tree is only two feet tall after 7 years, it will take a long time for that to happen. It you want to try to get the tree to fruit, you need to put it in full sunlight and fertilize it regularly. Or you can just enjoy the tree as a houseplant.

QUESTION: We have 4 live oaks in a diamond pattern: 75 feet long axis, 35 feet short axis. The trees range from 15 inches to 36 inches in diameter. We have a mobile home sitting in the middle for 20 years and wish to replace it with a more permanent structure. Would a cement slab or cement footing harm the tree roots? Should we use pier and beam construction (which limits what we want to do)? Should we install some sort of root watering system?

ANSWER: You will cut a few roots when you put the slab in, but that should not harm the trees. Probably the ideal situation would be to go with pier and beam, but the alternative would be alright as well. A root watering system will not be necessary. However, it is best if the structure can be at least 15 feet from the trees. This will drastically limit the size of the structure.

QUESTION: I have a loquat tree that produces a large amount of fruit. I eat the fruit and have had some fine jelly from loquats. I have read about loquat wine and am looking for a recipe.

ANSWER: Here is one recipe for wine.

One Gallon of Loquat wine
4 lbs of loquats
7 pints of water2 1/4 lbs of sugar
½ tsp of pectic enzyme
1 tsp yeast nutrient
1/16 tsp of potassium meta-bisulfite
1 pkg of champagne wine yeast

Strip the fruit off the stems and separate out any moldy or obvious bad fruit. Mash the loquats and strain thru a nylon bag into the primary fermented. Add all the other ingredients except the yeast. Tie off the nylon bag with the crushed fruit and put it in also. After 24 hours add the yeast. Cover the primary container and stir the must daily. In 6 days, squeeze the nylon bag as dry as possible and siphon the juice to a secondary container (glass jug) and fit an air lock. Check the air lock weekly and in two months siphon again. Keep checking every 2 months and siphoning again until clear. Sometimes it takes 6 months or a year. Then bottle and enjoy!

QUESTION: I have a Red Maple tree with a problem, I think. Most of the leaves are light green to yellow in color with green veins. The tree is around 15 years old with a 9" diameter three feet up from the ground. The grass in the yard has an even medium green color, no patches of different colors. I live in the northeast Fort Worth area. Other neighbors with Maple trees close by have normal looking dark green leaves. Any suggestions for improving the health of this tree?

ANSWER: While the chlorosis symptoms (light green leaves with dark green veins) suggests an iron deficiency, Michael A. Dirr in his book _Manual of Woody Landscape Plants_ says that in fact research has shown that manganese is most often the causal agent in maples.

This Michigan State web site gives more information about manganese deficiency in maples:

http://www.msue.msu.edu/msue/imp/mod03/01701133.html

"Manganese deficiency symptoms are most often seen on maples. Symptoms are yellow leaves with green veins. Most affected are the youngest leaves. Applying manganese chelates or using trunk implants will suppress the symptoms. Branches sprayed in the spring with a manganese chelate will green up if manganese is the deficient nutrient. Trunk implants will prevent the symptoms from occurring for more than one year. The tree should be kept healthy through fertilizing and watering so the implant wounds heal as quickly as possible. The disadvantage of this method is the need to drill holes in the trunk."

Your favorite nursery should be able to recommend to you a source of manganese.

QUESTION: I have a very uneven bermuda grass lawn ( low spots )at my home in Horseshoe Bay, TX., and wish to level it out. I am looking for information on how and when to best do this task. Questions I have are things like 1) When is best time (I assume approximately late March to early April ) 2) Should I aerate before top dressing 3) What type of soil should I use ( I assume a very sandy soil ). Is there anything else I should know about this process.

ANSWER: You can level bermudagrass plantings at any time of the year. I would not use pure sand or pure soil but a sand, soil, organic material (compost) mixture. You can aerate before top dressing since aeration helps bermuda at any time it occurs. I would make a fertilizer application every 30 days of a slow-release fertilizer such as 19-5-9 and apply an inch of water weekly.

Jim McAfee, Turfgrass Specialist at Dallas, adds:

1. The best time to topdress is when the turfgrass in the lawn is actively growing. For warm season grasses this would be late May to early September for most areas.

2. Never apply more than 1/4 to ½ inch of topdressing at one time. Too much material can create problems for the existing turfgrass. If you need to apply more than ½ inch, topdress twice. Wait approximately 30 to 45 days between topdressing.

3. Ideally, use a soil as similar to the existing soil as possible. A sand plus organic matter is alright, but I would rather use a loam type soil if possible.

QUESTION: How long should I wait to fertilize after installing a new lawn of St. Augustine?

ANSWER: The St. Augustine sod does not need to be fertilized until it has been down for at least 45 days. By then it should have its roots well established.

QUESTION: I just planted a 3 gallon Oleander. The one I just planted has one bloom on it. I realize it will take some time to get it to look like it should. Should I prune it and when?

ANSWER: The oleander requires very little in the way of attention or care. Oleanders are normally grown as multi-trunk shrubs in areas where they are subject to freeze damage. In frost free climates they can be grown as trees. If they do get frozen back, they are normally root hardy in our part of the world and will return vigorously from their roots. Use only 'Hardy Pink' or 'Hardy Red' varieties for minimum cold damage. Since they bloom on new growth, pruning is normally done just before they break dormancy in the spring. Tip pruning at that time will increase the fullness of the plant and therefore the blossoms. While it is no problem unless the plant material is ingested, you need to be aware that all portions of plant are extremely toxic. This means absolutely no marshmallow roasts using the stems for roasting sticks. The following information is from Botanica on CDRom:

Nerium oleander; Family name: Apocynaceae

Depending on the cultivar selected, these plants can grow from 6 - 12 ft (1.8 - 3.5 m) tall. As the species is often used for hedging, it is wise to keep the varying growth habits of the cultivars in mind if a uniform appearance is wanted. The blooms can be single or double, and some cultivars have variegated foliage. Some popular cultivars include 'Album' with single, white flowers and a cream center; 'Little Red' with single red flowers; 'Luteum Plenum' with creamy yellow double flowers; 'Mrs Fred Roeding' with salmon-pink double blooms and a relatively small growth habit; 'Petite Pink' with single pale pink flowers and growing only to 3 - 6 feet (1 - 1.8 m) tall; 'Punctatum', a vigorous plant with single, pale pink blooms; 'Splendens Variegatum' with pink double flowers and variegated gold-green foliage borne at the expense of the profuse flowering habit of its parent 'Splendens'; 'Algiers' has flowers with the darkest red color available; and those of 'Madonna Grandiflora' are double and white. 'Casablanca' (syn. 'Monica') has single, very pale pink, almost white flowers.

Hardiness zone from 9 To 11; Plant Height From approx. 120 To 330 cm; Flowering colors: Cream, Pink, Red, White, Yellow; Flowering season: Summer; Garden type: Seaside, Dry Garden, Hedge/Screen; Position: Sunny; Propagation season: Spring, Summer; Soil: Sandy Loam, Medium Loam; Other properties: Poisonous

Nerium Cultivation: Plant these shrubs in full sun and in well-drained soil. If they get overgrown and leggy, they can be rejuvenated by severe pruning in spring. In frosty climates they can be grown in containers and overwintered under glass. Propagate from seed in spring or from summer cuttings.

QUESTION: I am really interested in growing Olive trees that produce fruit. I wondered if there are any varieties that could be successful in the South Texas or West Texas area. I know that some olives are being grown in Texas but don't know exactly where.

ANSWER: Currently there are several experimental olive orchards in south Texas around Devine, Dilley and Asherton that are 3 to 4 years old. The biggest problem which olives face in south Texas is receiving enough cold to produce fruit, but not enough to kill the plants. An in-depth discussion of our current thinking on olives in Texas is outlined at the following Plantanswers site:

http://aggie-horticulture.tamu.edu/extension/fruit/olive/olive.html

QUESTION: Ever since Botany class two years ago, I have been obsessed with Palm trees, how they grow and develop. I know they are monocots, so there is no branching or lateral growth of any kind. What I want to know is how a palm gets to its particular width. I have been told that it will be the same width from the first to the last day of its life, but how does it get this wide from a single seed without lateral growth? Also, you see these palms that are shaped like a pineapple: the stem goes from one width at the base, wider toward the middle, then narrower again at the top. Is this just a visual effect created by the trimmed leaves or what?

ANSWER: I think palms have what is known as "diffuse" secondary growth. That is they add new xylem around the existing vascular bundles, but they do not grow from a typical vascular cambium as they age as dicot trees do. Palms do not germinate at the ultimate girth they will attain. They do continue some growth in girth as they age as they add new xylem around the existing vascular bundles.