First the question:
Does anyone have advice on whether ornamental crabapples serve as a host for the major apple pests of plum curculio, codling moth, and apple maggot?
The background:
I’m trying to estimate what I can expect for pest pressure to figure out how aggressive I need to be on spraying. Barring spring freezes, I expect to have a few fruit this year in some of my trees in their 3rd leaf.
I’m a backyard grower in a suburban neighborhood. There are a few established apples in the neighborhood, but many more ornamental crabs.
I would like to try mostly organic. I might bag fruit this year, but that sounds like a big pain for the long haul.
Organophosphates like Imidan are kind of scary to me from an applicator point of view, but I’m not too afraid of the other classes of pesticides and not fungicides. I had excellent foliar scab control last year with sulfur sprays.
My input will not conclusively answer your question but I do have a few observations that I have made over a long period of time. In my area for as long as I can remember many backyards have one apple tree (crabapple) growing and most are 15-25’. These trees in most cases have been planted and have no additional care other than trimming the limbs trimmed up so they can mow the grass under the limbs. These trees typically mature great quantities of apples almost every year. I’m not even sure if and how much these trees DNA are shared with the ornamental crabs. I have a few different crab varieties grafted and for the most part I have not noticed any pest damage (none are ornamental types). One of my varieties does get a little cedar apple rust but the others have not been touched. Bill
I have bagged for the last three years and you are right about the job getting tougher as the young trees produce more fruit. On the positive side bagging is mostly a one time job. If you use ziplock bags as I do you can sit back and watch them grow. The tree looks like your celebrating Halloween a little early. Bill
I call my three large weeping crabs the engine room of my orchards. As for pests, there are zero, as for CAR there is plenty and I must spray once in the spring. They insure pollination for my apples.
If you want to be as organic as possible it will help if you grow disease resistant trees. What varieties you grow? It seems varieties attract more troubles ( both diseases and bugs) than others.
I do have crabapple trees in my neighborhood. It does not seem to help reduce any pest pressure for my trees
I will continue to bag apples as long as the numbers are in the hundreds. If it gets to be 1000’s, I have to rethink my approach. My orchard is small so I may not get to that point.
@mamuang I am in SE Iowa. I am growing Zestar, Liberty, Kidd’s Orange Red, Enterprise, and Suncrisp for dessert apples, and Harrison, Dabinett, and Harry Master’s Jersey for cider. I also have a bacterial canker infected Redhaven peach that will get the chop if it doesn’t fruit this year in favor of pawpaw, and Alderman and Superior hybrid plums. So I really have a mix of disease-resistant and susceptible varieties. What do you use as bags? The sandwhich bag method sounds like making an apple tree sail in our 60+ mph summer storms.
Like I said, I don’t mind fungicides as much as pesticides. I would say, fortunately, the closest apple and crabapple trees live in well-kept yards, so the majority of scab innoculum gets mulched in and eaten by the worms. And thankfully I don’t have any neighbors with that favorite deer food of arbor vitae growing as fences or whatnot to harbor CAR.
I did some looking and the extension services say that the big three fruit pests of apple can use crabs as a host. I was thinking that the small fruit size might make things difficult for them. But I suppose they just crawl out and on to another fruitlet.
I have used zip lock plastic bags. I have found that when I cut a small slit in the middle for a stem to go through, I am able to zip the top very tightly. Howver, My orchard is in a protected area. It does not get gusty when like where you are.
