There are some rumors flying around the Internet about the threat of Formosan termites in mulch made of trees damaged in Hurricane Katrina. The rumors have implicated two national chains, Home Depot and Lowe's. Our state entomologist, Jeff Knight, made some recent comments regarding this.
I will summarize what he said in a couple of paragraphs. I will give you a full text of his comments if you send me an e-mail request at extremehort@aol.com. Those of you getting my electronic newsletter will get this as an attachment. You can request my free electronic newsletter by sending me an e-mail at the above address.
First of all, both Lowe's and Home Depot executives have made statements that the companies do not get mulch from Louisiana. Secondly, Louisiana has a quarantine to prevent the movement of any wood material out of infested parishes. Thirdly, if Formosan termite were to be transported to Southern Nevada it would be extremely difficult for it to survive in this climate, much less make it through the mulching process and then adapt to the area.
Knight enumerates the reasons why it would be highly improbable in the full text of his article.
Knight summarized, "With all these hurdles to overcome I feel the threat of Formosan termites being brought into Nevada from Louisiana in mulch is negligible, if not non-existent. However, in all cases we should always be watchful for this and other material that might be moved into Nevada in violation of any state or federal quarantine. In the future we should remember that any real threat like this will come through the normal USDA and State Department of Agriculture channels."
Mark your calendar for April 8 from 9 a.m. to noon at the orchard for a Master Gardener educational event on how to care for your fruit trees. The Master Gardeners will be covering how to thin fruit, how to fertilize trees, how to prune grapes and they'll answer all of your fruit questions.
Question: Could you explain a little more about how to thin fruit trees? I understand that one wants to thin the fruit while it is very small, about pea size. But how much? That is, how many fruits per cluster? Or, can one thin the flowers?
Answer: Those of you getting my electronic fruit newsletter will receive an expanded version in the next issue including pictures.
The very early peaches, like Florida Prince and Florida King -- provided some late freezing weather left you any fruit -- can be thinned starting now. Others can be thinned as fruit reaches thumbnail size.
Thinning flowers at the time of flowering actually is not a bad idea since the flowers are much easier to see than fruit, but it is possible you run the risk that a light fruit set plus thinning may leave you very little fruit left. But the fruit you will get will be huge.
A little background: fruit tree leaves can only produce a limited number of sugars for fruit development. So there is an optimum number of fruit that a tree can produce based upon how many leaves it has. The ratio of the number of leaves to fruit will determine the size and quality of the fruit it produces. This ratio is somewhere around 30 or 50 leaves per fruit.
The fruit tree wants to produce as much fruit as it can and quality is not an issue. We want high quality in our fruit and we are prepared to have fewer fruit if we can have a higher quality. If we leave the tree alone, it will normally produce lots of small fruits. If this is what you want, then don't thin the fruit.
The amount of thinning you do depends on the size of the fruit you are planning to get. Larger fruit like apples and pears need a distance of 6 to 8 inches apart for good sizing. When thinning apples and pears, remove all fruit in a cluster except the largest fruit. No doubles -- they will damage each other and provide a hiding place for bugs.
In some heavy producers the clusters may be too thick along a branch and you may have to remove all the fruit from clusters to get the right spacing. Apple fruit are sometimes tough to remove. You might want to take a small shears or scissors to remove the fruit.
Apples and pears normally produce fruit in clusters called spurs. Spurs are compressed branches that produce fruit. If your tree has lots of these compressed branches then you might consider removing some of the spurs so they are not spaced so closely together. In our climate, due to high light intensity and damage to fruit, I would remove spurs on the top side of the branches when spacing them.
Peaches and nectarines are thinned so that they are about 4 to 6 inches apart. Leave fruit that will more likely be shaded by leaves, on the bottom sides of the branches. Fruit should not be touching each other.
Apricots are thinned closer together, since the fruit does not get as large. Three to 4 inches apart is adequate.
Plums are borne in clusters, more like apples, and require lots of hand-thinning. They are thinned so that fruit are 3 to 4 inches apart like apricots. You can speed up the thinning of plums by shaking the branches lightly when fruit is about a half-inch in diameter. Then finish thinning by hand.
Asian pears are thinned like apples and pears. Pomegranates can be thinned as well. Leave only one fruit per cluster and remove flowers as they appear close to other fruit. Grapes are thinned by the bunch by pinching the bunches by about one-third and leaving only one bunch per foot.
Q: We have a problem with ants and I think they are eating the grass roots since our grass is fine in spring, then when the ants arrive it dies. What can I do about the ants, short of calling a pest control company?
A: Usually keeping the soil wet will drive ants out of the lawn area and into dryer areas. You will have to check labels but drenches containing pyrethrums or Neem oil will be irritating enough to drive them out of the area.
Q: The aphids are absolutely eating my beautiful pansies to death. I have used two different safe garden sprays on the pansies I have in two separate flower boxes. The one box that is up closer to the house seems to be more heavily loaded with these parasites. The flowers are just dying more every day no matter what I spray on them.
A: First, make sure they are aphids and not another type of insect. This will dictate the control method.
If soaps have not worked for you, then try the oils. The first oil I would try would be Neem oil. You should be able to find this at most nurseries. Thoroughly wet the foliage both on top and the bottom of the leaves. You will need to repeat the spray. I would also drench the soil surrounding the plant.
If Neem oil doesn't work then try the pyrethrum products. The label in large letters may not say pyrethrum so you may have to check the ingredients.
If pyrethrum doesn't work then you might have to try moving into the so called hard pesticides such as malathion or permethrin. Again, these words would be found in the ingredient list. Aphids usually migrate in from overwintering weeds. Make sure the area is cleaned up of weeds and spray surrounding plants that might harbor the insects. Control ants as well since ants will protect and encourage aphids.
Bob Morris is a horticulture specialist with the University of Nevada Cooperative Extension.
Archived Editions| Advertising | Contact The Staff
