bugs killing trees?, need help!

[flewism]

Hi, I'm usually on the firewood forum, but I pretty sure I have a bug problem and need advice. I have two small red trees in my front yard and today my wife said they were dying. This is what I found. all leaves are dead on this tree but, it is still alive based on the moisture in the small branches, I think

This is the second tree. Some leaves ae half dryed out and most have holes in them.

these last two pictures is what I found searching the second tree over closely

what is it? what can I spray to stop it? I have some seven in the barn , but it is a couple of years old. These trees have done well prior to this event. Any assistance would be appreciated.

 

[Urban Forester]

Those are Purple Leaf Plums, aka Sand Cherries. They are "ornamental" trees that are pretty much suseptible to just about everything... aphids, two or three different types of scale insects, cankerworm, japanese beetles, black knot, vascular canker and oh yeah they are grafted trees. The one that died, if it happened quickly and right after a year where it looked fine probably developed graft incompatability. That's were callus tissue forms around the cleft graft causing a blockage in the conductive tissue. The insect damage I see on the leaves could be any number of caterpillars or leaf beetles, since just about everything feeds on them. The insect pictured is probably not the culprit. A word of advice about sevin, its a very nasty 'old-school' pesticide that effects mamals blood when exposed to it. It depresses an enzyme in the blood that helps w/clotting, even minimal use over a long period of time can lead to cholinestrate depression as it has the ability to 'collect' in the blood. Its in the carbamate group of pesticides and most of them are being phased out. Not to mention it kills evrything it contacts, which means predators die as well. Back to the topic, these trees will need lots of TLC to survive and look good over their lifespan, which is about 25 years, god willing... If I was to implement a program to try and keep them from being eaten by insects I would do the following: 1) Dormant oil in mid April, 2) foliar spray in mid to late May and one more in mid June. if japanese beetles are a problem, one more treatment in mid july may be needed (Use a synthetic pyrethroid, not sevin). Then fertilize them in the fall w/a slow release fertilizer. There is nothing that can be done to avoid getting the vascular diseases I mentioned, other than to reduce stress and try and keep them healthy.

 

[flewism]

Great, just this morning I blasted them with Sevin, 1.5 oz per gallon and used 3 gallons on the two trees. I bought and planted these trees about 1999 within the first year we had this house. Saturday morning I watered them heavy, and sprayed this morning. It sounds like I'll be replacing them soon, and I believe it was a Lowes or home depot tree purchase. The wife really liked these trees as they added more color to the front landscaping. After the initial care for a couple of years these trees have been carefree for the last five years. They were healthy and strong in May of this year. I printed your instructions and thanks for you reply.

 

[treeseer]

Click the link in my sig and find Proper Mulching.

Please.

 

[mga]

Click the link in my sig and find Proper Mulching.

Please.

nice site...full of good info.

however, the past several years have been disastrous for us using mulch. apparently we have something called "shot gun fungus" growing in the mulch and every window of the house has to be scraped with a razor blade to remove the spots. the spots on the vinyl trim can not be removed.

this stuff even shoots itself on the cars parked in the driveway! everything i have read about it says there is no "cure", you can't kill it and there is nothing on the market that will safely remove it from vinyl.

the only way to get rid of it, "they' say, is to completely remove all the mulch and throw it out, which is too bad because we paid alot of money for the mulch.

so, people should be aware of shot gun fungus. it's some nasty stuff. if we looked into rubber mulch and brick chips, but i believe they must throw gold dust into them because the price is outrageous.

i may just stay away from "processed" mulch and just go with old wood chips instead. my theory is that when garden or landscape places store all that mulch, the fungus grows in it and when they deliver it......you get it.

 

[treeseer]

i may just stay away from "processed" mulch and just go with old wood chips instead. my theory is that when garden or landscape places store all that mulch, the fungus grows in it and when they deliver it......you get it.

Sounds like a plan. Shotgun fungus very easily controlled by just scraping it up and burying it when it appears, but mulch out of the chipper is fine for the tree.

Re the sand cherries, yes color is nice but real trees have good color too without the pests the short lifespan and the small size. Plant some big trees man--oak, sugar maple, pine...that yard is is 99% turf and 1% trees; should be the other way around.

 

[S Mc]

Did the first tree (in your photo lineup) show progressive symptoms or sudden event browning of the leaves? What does the base of the tree look like? I can't quite see it in the photo.

You have grass growing right up to the base of these trees which opens them up to the consequences of lawn mower and weedeater damage. You also have a turf which appears to be weed free, which suggests that herbicides have been used, which could also stress these trees. And stressed trees are more open to insect or pathogen attack.

As has been stated, trees in the Prunus family are, evidently, considered candy to insects. The little guy in your third photo appears to be a slug sawfly and causes exactly the kind of damage you see in that photo. As they feed in mass they can do a serious number on the foliage.

They over winter in the ground as full grown larvae, pupate and emerge as adults (a small, wasp-like critter) in late spring. My reference states that "little is known about natural enemies" and that they can be "dislodged with a strong jet of water". I must confess, if the larvae can overwinter in the ground, dislodging them with a strong jet of water doesn't sound like it would be helpful. Insecticidal soaps may be effective and you can simply pick them off and dump them in a bucket filled with soapy water to reduce the population.

There are "several insecticides labeled for use on slug sawflies; B.t. is not effective on sawflies".

As these are small trees that you could culturally manage, I would encourage doing so rather than pumping chemicals. But that is just me.

I would also encourage you to consider some longer-lived species for your landscape. Perhaps you have other trees on your property that just don't show in this photo. These two are already ten years old and, as pointed out, they don't have a long lifespan in the best of circumstances. Waiting until they succumb leaves you with nothing while you wait for new plantings to become established. This is a reason why we suggest diversity of size, longevity and color...to maximize longterm enjoyment of your landscape.

Sylvia