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Crabapple tree has apple rust fungus - suggestions?

13 years ago

I bought a new construction house and the builder had planted a new crapapple tree in the front yard. It grew a lot this year and doubled in height to about 6' now, but has the apple rust fungus. I'd say about half the leaves are affected now.

What to do now? Should I clip the affect leaves and dispose of them or leave them? Spray fungicide?

Any help would be appreciated.

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Comments (14)

ken_adrian Adrian MI cold Z5
13 years ago
arent the leaves going to fall off in a few weeks??? why waste effort and chemicals ?????

full and complete clean up of dropped leaves ....

and PERHAPS some spray in spring ....

too bad he didnt plant a tree that had reduced susceptibility ....

ken
Dan _Staley (5b Sunset 2B AHS 7)
13 years ago
Basic sanitation by picking up all (a-l-l) leaves and fruit. Dormant spray. If you tire of the routine of cleanup and dormant spray every single season, remove tree and plant a resistant variety.

Dan
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mkiv808
Original Author
13 years ago
Yeah, seriously thinking of replacing it with a dogwood.
Embothrium
13 years ago
Cut it down. With successful variety selection you can still have a crab apple, should you desire, without rust. There are hundreds of kinds.
ken_adrian Adrian MI cold Z5
13 years ago
listen.. gardens are not hospital operating rooms ...

if you ignore the rust.. you will have a nice crabapple .. which will lose its leaves a bit early in the season.. SO WHAT??????

its not going to poison you ...

its not going to spread all over the yard ...

why dont you work around it .. adding some other landscape.. and in a few years.. if its still bugging you ... then get rid of it ...

if budget is of no issue... and all the power to you ... then be done with it.. and order up another couple thousand dollars of landscape material ... what the heck.. eh ...

but in my world.. EVERY plant has its season.. and for gorgeous spring flowering trees.. the crabs .. with or without the rust.. are simply stunning at that time.. wouldnt be without them ... but then i have 5 acres.. and nothing is really a specific focus .... if its your only tree... i can see being done with it ....

by the time they have the uglies.. in august ... and in fall .. i have a couple hundred conifers that are just making me very happy.. and i really have no focus on that ugly crabapple ...

good luck

ken
rhizo_1 (North AL) zone 7
13 years ago
ken, I don't think that even YOU believe what you just said! lolol

I've 'heard' you suggest many a time to remove a plant that someone is unhappy with (for whatever reason). Especially if the offending plant is right in their front or back yard.

mkiv, be sure to do a bit of research on dogwoods in your location. They are not a disease free species, by ANY means. You can, however, purchase resistant hybrids.
mkiv808
Original Author
13 years ago
Ken - it's the sole focal point of the front yard. I have a small property (.10 acre), so I don't have a whole lot of room. I need a really beautiful tree as a focal point in front of the house. The rust actually started happening in June or July and got really bad the last couple of months.

There's a great tree at my old condo that I would love to have. It looks almost like a white flowering dog wood. It looks like there's multiple trunks and the branches twist and extend horizontally. It very much looks "Asian" or "Japanese". It's about 20' tall with a 15' spread. The flowers are white with a sliver of purple on them.

I can try and take pics. Probably going to be tough to identify the exact tree though.

It's somewhat similar to the below tree, but with even more twisting and horizontal growing of the branches, lending to the Asian look.

{{gwi:446998}}
ken_adrian Adrian MI cold Z5
13 years ago
if you dont like it.. and its bugging you.. and space is limited...

WHY IS IT STILL THERE..

BE DONE WITH IT!!!!!

no guilt ... and i would not have wasted the time online getting justification.. it would have been gone by the time it took you to type the first post.. lol ...

ken

ps: is this more of what you expected rhiz??? ...lol
rhizo_1 (North AL) zone 7
13 years ago
Eggactly! That's the ken we all love.
daniel_cl
13 years ago
I am in a very similar situation: new house, new crabapple tree ('snowdrift') at front, severe black/brown dots on the leaves. The snowdrift cultivar is supposed to have medium-high resistance to the scab... perhaps this fungus is a new strain? The tree was also planted 8" too deeply in our heavy clay, which suffocates the tree and makes it susceptible to disease. We just replanted this past weekend.

From what I read, these fungus/bacterial infection does not live on the tree, they drop with the affected leaves and wait to re-infect the tree's new leaves next spring. Hope you are lucky to have powerful winds (we do) to minimize maintenance effort.

All trees have their respective problems and benefits. Crabapples give stinky fruits and brown leaves in the fall in exchange for unequaled spring flowers, reduced insect problems and heavy clay tolerance. Even we originally wanted a serviceberry from the city (which gave it to our neighbor), we will take care of the crabapple as best as we can.

In order to shift the attention in the fall, we planted a cutleaf staghorn sumac. Very, very nice shrub!
mkiv808
Original Author
13 years ago
How resistant to this fungus are white flowering dogwoods or autumn cherries?

http://www.fast-growing-trees.com/WhiteFloweringDogwood1.htm
http://www.fast-growing-trees.com/AutumnCherry.htm
aegis1000
13 years ago
Dogwoods aren't susceptible to this fungus, but can have other fungal problems. In a front yard setting, with plenty of sun, a Dogwood should be okay.

However, Dogwoods generally have slow to moderate growth, but are gorgeous in the Spring and, often, have nice red foliage in the fall. It's a nice small tree, just not fast growing.

Cherry trees can be problematic. For one, your soil and drainage needs to be about perfect, and there are diseases and pests to deal with with them also.

For a fast-growing small ornamental tree, a newer crabapple (one with resistance to fungal disease) might be ideal for you.

Or maybe a magnolia ?
spedigrees z4VT
13 years ago
Thank you for your words, Ken. Is it also true that apple scab will not actually kill a flowering crabapple, but just cause it to lose its leaves early in the season?

I've been worrying about the flowering crab that I planted this past spring. I controlled the fungus with a paste of captan, as well as picking up the fallen leaves and disposing of them, but I won't be able to treat the tree when it gets bigger.

Anyways I'm definitely not prone to removing an established planted tree. A disease resistent variety is liable to become non-resistent over time as the fungus mutates, anyways, from what I've heard, so replacing established apple trees with new trees seems like an exercise in futility and a waste of time and effort to me.

Time will tell I suppose but I'm hoping all my apples and crabapples can live despite the fungi, just as my white pines seem to thrive in spite of the pine weevil.
mkiv808
Original Author
13 years ago
I got a kousa dogwood. Should be resistant to disease and looks right.

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