Probably scale insects. At first I thought you were asking about the speckling of the leaves. That could be bugs, too. Look for them on leaf undersides.

Check to see if there are aphids under that white waxy stuff. The aphids will be kind of a brownish red to purple. If so, you have woolly apple aphid. They also infest the roots esp in soil that cracks when dry. They can stunt the tree. Best control is a resistant rootstock such as EMLA 106.

The Fruitnut

Most likely woolly apple aphids. To know for certain, squish them. As has been said, you'll see purple stain.

thanks people. how are woolly apple aphids controlled?

They're not.

The problem is that they spend the winter underground on the roots, then migrate upstairs in spring.

You can limit the population somehwat with sticky tape around the trunk to "catch" them as they migrate upward in spring and downward in fall.

You can also physically remove what you see topside.

Nothing is available for home garden management of the underground fellows.

Some kinds of apples seem to be affected more often than others. At least that was so in my SoCal garden. I kept the affected tree because it did fine as far as producing apples for my needs.

Yeah, of course: woolly apple aphid. I like that better.

Lychee:

I would not disagree with Jean or B-boy about the Woolies and their habits, and the difficulty of control once they are established.

But I think it would be worth a couple of applications of dormant oil to at least give it a try; one on a warm day in about mid-February, and the second just before the buds break. Use a full-bore, paraffin-based oil, not the lightweight "summer" oils, or any vegetable based oil. Mix up the oil full-strength, or even a little stronger than recommended, and make sure you get full coverage of the tree from top to bottom.

I used to have problems with several types of aphids, but since I began the dormant spray program they have been pretty well eliminated, even though I do not spray the apples with insecticides during the growing season thanks to bagging the fruit in ziplocks. Even if you can't eliminate the woolies completely, you ought to be able to slow them down.

Don Yellman, Great Falls, VA

thanks for the helpful advice everyone.

I have had them several times. I would take a paper towel or similar and clean them up by hand, followed by a spray of soap or oil, and they wouldn't come back. Maybe I have been lucky but based on my experience I wish all pests were as easy to deal with. I also agree with Don on the usefulness of a dormant oil spray for aphids in general.

Scott

Wooly apple aphids are omnipresent in most of my orchards that have old apple trees. Apparently there is adequate predation to keep them under control because they never seem to cause much damage.

As easy as it is to type out a question on-line and get a mixture of advice I will stress again the usefulness of cooperative extension to get specific local advice for controlling pests. This is not to replace the friendly and often knowledgeable guidence you receive here but to augment it. You need local advice to help with timing of application and pesticide options.

A pesticide that is restricted in one state may be readily available in another. The life-cycle and severity of most pests vary from region to region.

Every state has a county to county network of links to their designated land-grant agricultural college, I believe. Look in the government pages under county listings.

I have heard of this problem before that local extensions are lacking in expert advice. In New York we have Cornell which is one of the nations best ag schools so maybe I'm spoiled but I don't understand why it matters if the University is 300 miles away if you are aggressive in seeking help.

The advice on a site like this is unreliable because no one is accountable and well meaning people can make recommendations that are legal in their state but not the state that the one asking questions lives. You also never know the training of the respondent.

Do you know of any state where Diazanon is not restricted? I don't, but one participant indicated that it is everywhere restricted. I wouldn't be surprised if there are no restrictions on it in some of the Southern states and that a home orchardist could pick some up to treat woolly apple aphid. You could be sure of the info if you got it from cooperative extension.

Now in your state have you asked to be put in touch with specialists at the University? I would think that there is a fruit tree patholigist and also an entimologist who would answer your phone calls as well as at least one pomologist who guides the local commercial growers.

Cornell doesn't have anywhere near all the information I need but the information they do have includes far more sophisticated diagnostics that you will find on a web site like this.

Harvestman:

I think we are just going to have to agree to disagree here. Nothing wrong with that. Given the choice of doing things the easy way and the hard way, I usually choose the easy way, and I am quite satisfied with the content and reliability of information I can find from university websites and forums like this one.

Of course, participation in forums like Gardenweb is entirely voluntary, and I don't expect to hold anyone "accountable" for information I find here.

With respect to your specific comments on insecticides, it is my understanding that the EPA objective is to remove the entire class of insecticides known as organophosphates from the consumer market, and yes, it is a national policy.

Don Yellman, Great Falls, VA

But you're cooperative extension could tell you if let's say Imidan is restricted in your state- national policy doesn't matter unless it overides state law. Imidan is not restricted in CT but is in NY. Now until it is taken off the market it is probably your best tool against PC. This is the kind of info I'm talking about.

Also if you need some microscopic disease and insect diagnostics or leaf or soil analysis. How are you going to find out on line how much lime you need to bring your soil to the proper pH when you're not highly experienced. If you trust the info on the bag you will add a fraction of the requirement.

It's hard for me to understand what you're disaggreeing with. I wouldn't be participating with this forum if I didn't think it was useful and the internet is a great tool but your taxes are paying for this other resource and even if you personally have no use for it you should see how it could be useful to others. In my business, and the reason I use the silly moniker "Harvest Man" is that I have to get reliable results. It's all about the harvest.
I use all available resources and as a result I make a decent living. Your comment about not wanting to waste time is silly- I can't afford to waste time either. Actually I'm probably wasting my time right now.

sorry about the "probably wasting time" sentence, it was supposed to be funny but reads really pompous.

sorry about the "probably wasting time" sentence, it was supposed to be funny but reads really pompous.

I doubt if anyone is still tuned in after all my babble, but I just picked up my 2007 Pest Management Guidelines for Commercial Tree-Fruit Production from my Cornell Cooperative Extension in which they recommend Assail (Acetmiprid)for use against woolly apple aphid, applied in mid-summer.

This is a non-restricted pesticide in NY state where all OP's are now restricted. It is also affective against PC and most of the other damaging insects including apple maggot, scale, sawfly, etc etc. It's probably quite expensive and home-orchardists would have to purchase enough for 2 lifetimes so you might want to be sure damage has passed a tolerable threshold before looking into it.

If you want further info on waa they publish a sheet on its lifecyle and control which you probably can find on line.