Shop Products
Houzz Logo Print
michael357

Apple leaf disease mystery w/pics

Michael
14 years ago

Howdy all:

I was root'n around my Freedom tree yesterday and noticed a very noticeable case of these spots. There is a pretty strong tendency for the younger leaves and those on the shoots, particularly towards the outside of the canopy to have the worst and most dense symptoms. Deep within the canopy and on spur leaves there is very little of this symptom. Any educated/experienced guesses? I don't expect it is CAR or scab (good resistance) having seen very little to none respectively in previous years. I do live in a severe CAR belt and didn't spray the tree for CAR and scab this year or the previous 2. All the images I've seen of scab don't look like this either.

I sprayed w/stylet oil several weeks ago but the temps. were in the mid to upper 70s for the 2 morning sprays and never got past low 80s both days.

{{gwi:104486}}

{{gwi:117433}}

Thanks in advance, Michael

Comments (8)

  • jellyman
    14 years ago

    Michael:

    Those spots look like cedar apple rust to me, and I have a lot of it unless I spray preventives during the windy, rainy weeks of late March and throughout April. I use a fungicide called Ferbam, but many others are using a Spectracide product called Immunox, which has the fungicide myclobutanil as its primary active ingredient. It is a systemic, and it might actually be better than Ferbam against CAR since it doesn't have to be repeated so often.

    I also have a Freedom apple tree; mine is about 15 years old. It may be resistant to CAR, but it is not immune. I don't worry too much about a few CAR spots on the leaves. My primary concern is with the apples themselves, which can be 95% ruined by this disease in a windy, rainy spring with particularly active CAR spores. This has happened to me several times over the years, and I am highly vigilant about CAR now, which for me means spraying early and often. Oil sprays and ordinary garden-variety fungicides are not effective against this disease. You may not see CAR every season where you live, but every year is different, because of varying weather conditions and the number of active galls on the cedar trees. The area where I live has a very high cedar population that has naturalized everywhere.

    Don Yellman, Great Falls, VA

  • Scott F Smith
    14 years ago

    Michael, I also have some of that this year and I thought it was CAR but I noticed it never has the bumpy stuff on the underside of the leaf like CAR spots. I also have a tree that has both those kinds of spots and CAR and they appear to be different. My conclusion was it was frog-eye leaf spot. Gogle for pictures. There is also some chance it is CAR spots where the fungus failed to take hold, but my money is on frog-eye leaf spot.

    Scott

  • Scott F Smith
    14 years ago

    Well I just inspected my tree with both kinds of spots on the same leaf and none of the CAR spots on those leaves had the hairy bits underneath meaning they were not fully developed CAR spots. So those spots could well be aborted CAR injury, where e.g. the weather conditions changed to the disadvantage of the fungus at a critical time. So I'm changing my bet to CAR, but still am not certain. I would look to see if you have any spots with yellow on them (live CAR fungus). I doubt it all died already. If you have some yellow spots, it is likely CAR. If not, it could be either CAR or frogeye.

    Scott

  • glenn_russell
    14 years ago

    Hi Jellyman-
    Michael357 was the Immunox expert before Harvestman came (back?) on the scene with Myclobutanil information. The information from both he and Harvestman has been invaluable to me. :-)

    Scott/Mike - I believe in both (CAR or FrogEye Leaf Spot) cases, Immunox (which he already has/uses for CAR) would be a good preventer. Do you agree?
    -Glenn

  • rhizo_1 (North AL) zone 7
    14 years ago

    I first thought of frog eye fungus, fairly common to apples.

  • Michael
    Original Author
    14 years ago

    Thank you all again:

    Don, the oil was for the mite explosion and worked very well. In the past 2 years the tree has shown some of the yellowish spots which I recognize as CAR but they have been few and far between and never developed past a wimpy infection. This year I never saw a single one of those spots which would have developed further into what I once saw on the Jonafree one year before I knew what CAR was, what it looked like and began using Immunox. This year the CAR spore releases wer spread out over about a 6 week period due to several light rains, pain in the butt for my spray schedule. All the other trees were sprayed and look fine. The tree is certainly resistant but is not immune if symptoms are the judging factor. Didn't realize the CAR could hammer the fruit also, guess I'll add it to the spray schedule in the future. BTW, bagging the fruit last season may have avoided the summer diseases. Every apple tree in town had flyspeck and sooty mold on all the fruit, mine had none at all, hope that continues to be the case.

    Glenn/Scott: I looked up FELS and examined leaves w/the 14x loupe, can't see anything resembling fungal structures, an outer ring or dark speck in the middle. It really looks like something was splattered on the leaves that killed the cells only where it landed but the Jonafree next to it looks fine (it received the spring fungicide sprays as well as well as the oil sprays). The Freedom fruit looks fine too, so far. I don't know.

    Here is a blow up of the spots on the upper leaf surface. Not as good detail as with the loupe.

    {{gwi:117434}}

    Michael

  • zestfest
    10 years ago

    Michael, did you ever figure out what those spots were? I'm having a similar problem (see link below) and am curious if you solved yours...

    Here is a link that might be useful: my apple tree brown spots

  • KG_in_CT
    10 years ago

    Michael,

    Do you notice that the new leaves do not have this problem, say the leaves that have come out since the last time you sprayed?