QUESTION: I have exposed the root flare on a tree near my house. Is it OK to put 1-inch-diameter rocks into the 4-inch-deep hole that the exposure created? Should I cover the bottom of the hole with landscape cloth before adding rocks? B.Q., Dallas
ANSWER: The answer to both of your ideas is no. Leave the root flare area exposed to the air. The tree trunk and root flare eventually will grow and expand to fill the depression around the base of the tree. Putting anything into the depression will cause the area to become a problem again.
QUESTION: I treated a fungus on my St. Augustine lawn, but now the grass is yellow. What can I do to restore it? I am not on an organic program because it would be expensive to convert a large lawn to organic care. T.R., Fort Worth
ANSWER: An organic program doesn't cost more than using chemicals. You will use fertilizers less often and have fewer insect pests and diseases, fewer dead plants and lower water bills.Apply 15 pounds of an organic lawn fertilizer now for each 1,000 square feet of grass and spray the lawn with Garrett Juice and Thrive by Alpha BioSystems. Apply 40 pounds of Texas greensand for each 1,000 square feet of grass.
QUESTION: I have two live oaks. One tree produces many acorns each year, while the other produces very few. The first live oak seldom has small trees sprouting near it. The other tree, which produces few acorns, has many seedlings sprouting around it. How can I get rid of this problem? J.D., Garland
ANSWER: Heavy production of acorns typically is a response to weather and environmental conditions. When plants are in stress from extreme weather such as heavy rainfall, drought and unusual heat, they tend to produce large quantities of seeds. Small trees that sprout from seeds (acorns in this case) are easy to get rid of by pulling them or cutting them. However, if the small trees are root sprouts, they will continue to occur. Applying about an inch of compost annually over the entire root zone seems to reduce the growth of root sprouts.
QUESTION: My Bradford pear trees appear to be dying. The leaves are turning light green and then brown starting at the top of the trees. These trees were planted five years ago. Two years ago, I planted flowers around the base of each tree. Could that be the problem? I bought Bayer Advanced Tree & Shrub Protect & Feed and used it recently, but the situation has not improved. What should I do? G.B., DeSoto
ANSWER: Chemical treatments are not the solution. Flower beds around a tree often create problems because they usually add soil near the root flare and tree trunk. Most Bradford pears are planted too deep, and planting beds compound the problem. Remove the flowers and carefully excavate excess soil down to the point where the trees' root flares are exposed. After that, use my Sick Tree Treatment.
QUESTION: Our evergreens are infested with bagworms. These pests make cocoons that resemble small pine cones. Online research indicates that the best remedy is to pull the bags off of the trees and burn the cocoons to kill the worms. This would take many hours. We have five large evergreens that I don't want to lose, but we stopped after four exhausting hours of bag-picking. J.V., Dallas
ANSWER: Bagworms are caterpillars that are the offspring of a moth, Thyridopteryx ephemeraeformis (Haworth). Caterpillars build leafy cocoons while eating foliage. Later, the males develop into small moths with hairy bodies and transparent wings that mate with wingless females inside nearby cocoons. The female pupae remain inside their cocoons, where they lay hundreds of eggs that will hatch in the spring to start the next cycle of caterpillars and moths. After laying eggs, the females drop from the cocoons and die. If caterpillars are still eating foliage and dragging small leafy cocoons, they can be killed easily by spraying them with an orange oil solution (mix 2 ounces of orange oil into a gallon of water) or by spraying them with EcoSmart Organic Insect Killer. Bt (Bacillus thuringiensis) products also could be sprayed while caterpillars are foraging, but the spray may kill butterfly caterpillars, too. After full-size bagworm cocoons are hanging on the tree, physical removal is the only viable solution. Squash each cocoon between your fingers to kill the caterpillar or pupa that may be inside. Dispose of the cocoons in a compost pile. Burning the cocoons is not a good idea because smoke and fumes pollute the air, and the fire could get out of control.
QUESTION: How can I get rid of gophers in the yard and garden? S.L., Dallas
ANSWER: In some cases, moles and gophers can be repelled with hot-pepper and castor oil products or home mixtures of these ingredients. Injecting the materials into the soil is more effective than spraying the soil surface. Planting castor beans around the perimeter of the garden also can help discourage gophers. The best commercial repellent I have seen is Gopher Scram.