Bucky, I got a 4# bag of Kocide 3000 from Johnnys Seed. The 3000 is a new lower percent copper that works better because it is finely ground. As you know copper sanitizes dormant trees of fungus and bacteria.

Bucky,

There's not much fall/winter spraying that is necessary. Most dormant (or delayed dormant) spraying occurs in the early spring.

Mildew will not be controlled by dormant spraying.

Horticultural/dormant oil is generally applied in the spring as a dormant or delayed dormant application. At this stage it is primarily targeting mites, scale, and aphids. Oil can be used for mildew, but must be applied later in the spring and directly on the foliage (at a lower rate). There are fungicides that provide a higher level of control than oil.

There have been a lot of questions lately about horticultural oil. Here are a few points:

Most horticultural oils are basically mineral oil. There used to be a difference in horticultural oils, some limited to dormant use, and others able to be used during the growing season. With improvements in refining methods, most horticultural oils now can be used in the dormant and summer seasons. If the oil has the words, "narrow range", or "superior", or "supreme". It can be used as both a dormant and summer oil (of course check the label to be sure).

New oils evaporate very quickly, and are not phytotoxic to most tree fruit tissues. Spraying oil during high humidity/slow drying conditions reduces evaporation and increases phytotoxicity. Also avoid spraying oil if it is expected to freeze within 48 hrs. Spraying sulfur or sulfur products (i.e. captan) within close proximity of an oil application also increases chances of phytotoxicity.

The shothole on peaches is probably caused by bacterial spot. As Ace mentioned, copper is a bactericide and fungicide, although it is more effective against peach leaf curl, than bacterial spot.

So in short, there's just not a lot you can control with dormant spraying. Most of the spraying occurs in the growing season, when the pests are active.

A lot of what Olpea states should be on the label. It's very important to read that label thoroughly, preferably well before it's time to spray. Chances are the oil label will also caution about spraying at temperatures above 90 or so. Pears and some apples are particularly subject to damage under hot conditions. I have damaged trees with oil on several occassions- usually because of Captan, sprayed over 10 days prior. No warning on label about that. I've also sprayed right before an unpredicted hot day and caused some damage.

Aphids are not a big issue, but do slow down summer growth, however ladybugs should come to the rescue if you don't use an insecticide control. More problematic to summer growth for apples, (and Euro plums) in NY and probably PA, are leaf-hoppers, which have fewer natural enemies.

They tend to dry out the growing tips towards mid to late June and you can see them hopping off when you reach to touch those growing tips. Probably because of all the rain, they didn't do much damage this year for the first time in memory. They are only a big problem, though, when you are establishing trees and need rapid growth. On establishied trees they may be doing you a favor by slowing vegetative growth.

If I opt for chemical control of these pests I only spray growing tips. Malathion for aphids and Sevin for leaf-hoppers.

I agree with all that is posted: There's not too much you can do in the fall and the winter. Dormant oil doesn't do too much for you. But, what it does do, is still worth doing because it's pretty benign (organic). If you're interested in fighting Scab, and protecting against Fire Blight, like the AceOfSpades says, get yourself some Kocide3000 and mix it in with the dormant oil. When you do that, the oil now does double duty: 1.) It does what dormant oil normally does... plus 2.) It acts as a sticker for the Kocide. According to Scott Smith, this can be done in late November when the trees go dormant. Then do this again in early to mid April at, or just prior to bud break (green tip). I didn't get to the Nov spray last year, and I don't think it hurt me all that much, but I hope to do it this year. I believe the spring one is more critical. Just use the Kocide sparingly as after many many years, it builds up in the soil and becomes toxic to worms. Hope this helps...
-Glenn

"I have damaged trees with oil on several occassions- usually because of Captan, sprayed over 10 days prior."

Hman, I'm glad you chimed in. How close an interval do you find you can spray oil and Captan without burning foliage? Do you find it makes a difference in the interval whether the Captan is sprayed BEFORE or AFTER the oil application?

I plan to use more pyrethroids next year to keep the stink bugs down and will probably add oil to slow mites. As I use Captan in my fungicide rotation, I'd like to know how close I can apply it to an oil spray. I've always read two weeks, which is what I've observed, but I know you've applied it closer than that.

Does anyone have a good source to buy the Kocide, Captan, and Dormant oil? The aphids were pretty bad on one of my three year old trees. Made a lot of the leaves curl and the aborted the few apples that i let grow. There were two different kinds of them.

Here is the link that AceOfSpades mentioned. It's also where I got my Kocide3000.
-Glenn

Here is a link that might be useful: Kocide3000 at Johnny's Seeds

I don't use Captan, but I my local Agway has it, along with the dormant oil. Is there an Agway near you?
-Glenn

Olpea, first you should know that damage has generally been cosmetic with the possible exception of causing fruit drop for a couple varieties few grow, including Tompkins King. The interval from Cap to oil was 12 days when I got a suspicious amount of fruit drop going with 2 varieties that showed phytotoxisity to foliage. This was TK and another unidentified variety with probably Cox as a parent. It was sold by the nursery as Cox but is much sweeter. This was out of at least 30 other varieties which were unaffected on the same site.

I've burned pear foliage both by spraying when it was too hot and also once when I sprayed with a slight mist falling- I know, pretty stupid, but the label didn't warn not to spray during poor drying conditions only not during "uneven" drying conditions. Fortunately it was my own trees and a long time ago. It looked a bit bad but didn't affect the crop measurably.

No agways close but a farm stores ill check. 5 trees that will be in their 4th spring that i want to get some fruit off of next year. So far i have got 2 apples off of them. I thought they looked really good heading into this year but they didnt start out very well. Had someone stop by that knew more than me and he told me it looked like powdery mildew. So i want to nip it in the but in hopes i get a small crop this year.

You are all being very polite and restrained. I'm afraid my vulgar sense of humour couldn't resist checking out a thread on 'Fall/Winter spaying'. Or maybe it's not a term you use in the US? But then Bucky does say s/he wants to 'nip it in the but' so maybe subconsciously .... Sorry. Very infantile.

flora_uk, that's what got my interest too. Personally I wish I could fall/winter spay all the squirrels in my neighborhood!

I do have a real question, however. I'd like to dormant spray, but also whitewash my stone fruit trunks. Which order should this be done in? Is is possible to mix the paint with the dormant oil, or should it be separated out?

Thanks Hman,

I knew there are a lot of variables that interact with the oil's effect on the foliage (variety, weather, etc) but I thought you'd have some helpful observations. I appreciate it.

Milehigh,

I doubt it makes much difference in the order you apply oil and paint. However, I don't see any reason why you'd want to add oil to paint. If you mix paint with water 50/50, it's probably going to smother any insects, as well as plain oil (on the trunk, that is). Of course you'd still have to spray the rest of the tree with oil.

Might mention I've read a fall oil application can make trees more susc. to winter injury. Might be something for you to consider in the mile-high city.

I have heard that Daconil (chlorothalonil) when sprayed at half inch green can control powder mildew with just one application.

I'll find out if that is true next year . . .

Ok lets add to my problems at least the lesser peach tree borer. I have seen the moths around my place and i was dumb enough to use limb spreaders on my one peach tree that punctured the bark. What can be done to control them now? Im looking at brown rot and it does looks kinda like what my peaches look like but doesnt look like it. Mine are just getting a brown calus looking thing on about 20% of the peach. Ill try to get some pics when i get home. Any ideas what this could be?

Lifespeed,

Because mildew grows under low moisture conditions (i.e. dew) and it is impossible to eradicate on the tissues, it is unlikely, one application of fungicide will do the trick. As long as there is dew, favorable temperatures, and no fungicide residues on the tissues, the fungus will continue to grow, regardless of past fungicide applications. I've had some minor problems with mildew that have been controlled with fungicide sprays, but I've never experimented on how few it takes to achieve control. As I recall, the spray guides recommend three or four sprays beginning around first cover.

I'll also mention chlorothalonil is not highly rated for mildew. Myclobutanil (Immunox) is recommended and widely available.