Whitewash trees

[M.D. Vaden]

Without asking the tree painters, it can amount to 2 guesses:

Sunscald prevention: the name being very misleading since it's freezing that finalizes the damage.

And Sunburn prevention: where the sunlight / energy finalizes the damage.

Too many people confuse the two, and almost half as many don't really know how to deal with the problems.

There are solutions though.

The painting method for the winter protection could be tested using two thermometers that were calibrated, and inserted virtually "skin deep" to see if it makes a difference.

One problem - I have not read any research that discusses "sunscald" from an angle of whether or not it's the sunlight (rather than just the warmth) that triggers cell activity versus just the temperature increase.

I just compiled an article on these two - sunburn / sunscald (not the only reason people whitewash). And I found the 2 problems to be among the most challenging to sift through the diversity of opinions and differences of information - even from reputable sources.

They all are in agreement that:

There is sunburn
There is sunscald

Solutions? Much longer explanation.

 

[kapow2826]

Vet. Blind Rehab.

An expert who capitalizes every word?

I AM LEGELY BLIND. CAPS ARE EASYER TO SEE. THANKS TO THE VETERENS BLIND REHAB , I NOW HAVE A OOM TECH MAGNIFIED COMUPTER.

KAPOW2826

 

[lxt]

Without asking the tree painters, it can amount to 2 guesses:

Sunscald prevention: the name being very misleading since it's freezing that finalizes the damage.

And Sunburn prevention: where the sunlight / energy finalizes the damage.

Too many people confuse the two, and almost half as many don't really know how to deal with the problems.

There are solutions though.

The painting method for the winter protection could be tested using two thermometers that were calibrated, and inserted virtually "skin deep" to see if it makes a difference.

One problem - I have not read any research that discusses "sunscald" from an angle of whether or not it's the sunlight (rather than just the warmth) that triggers cell activity versus just the temperature increase.

I just compiled an article on these two - sunburn / sunscald (not the only reason people whitewash). And I found the 2 problems to be among the most challenging to sift through the diversity of opinions and differences of information - even from reputable sources.

They all are in agreement that:

There is sunburn
There is sunscald

Solutions? Much longer explanation.

Sunscald, injury to leaves, bark, underlying tissue of woody plants due to the combined effects of heat, humidity & intense direct sunlight & even indirect sunlight!! the extreme & continuous effect "scalds" the tissue!!

the winter or cool season injury is questionable & is thought to pertain more to frost crack as the damage is usually contained to one side of the tree(west side). the "winter, cool season" injury is debated amongst tree & plant biologists as well as others in regards to sunscald.

the freezing or cooling theory in order to be substantiated would require extreme temp. fluctuations that would be zone specific. For this very reason, many have seemingly been misinformed & thus inadvertantly provided wrong information about sunscald as a "cool/winter season effect"

the next is Sunburn & as stated in the quoted post leaves many with the wrong impression, neither of the definitions are true "sunlight/energy"..... the real culprit here is UV radiation through overexposure!! I would suggest problems within either of these two areas that one should consult with an expert in the field regarding "the radiation/thermal exposure effects to plant & tree health".

the above quoted post is a common misunderstanding amongst those who have not had proper enlightenment through the scientific field!!

I dont even begin to understand some of the scientific data relating to such, however I have used Penn State Universities lab`s(not personally used them) but met with & aided the white coats & have stood there conversing with them in depth about many things tree & plant related. they have a wonderful enviromental sciences Lab.

in conclusion Ill take the advice & info given by the white coats that have PHD behind their name!!


LXT............

 

[M.D. Vaden]

From what I've been seeing, sunscald is the most common figure of speech for the winter injury. Caused by quick freeze at night, shade or dark, after a bright sunny day.

And Sunburn, which is the more common term chosen for damage to tissue in the summer time.

Some people use the term "sunscorch" for leaf damage. And the terms are interchanged by quite a few people. The interchanging of terms really seems to throw a wrench in the issue for some folks.

The factual existence of "sunscald" is virtually etched in stone for evidence, due to the damage showing it's face in winter, on the sunny side of the trunk, but not the shaded side. Which rules out warm ambient temperature, and pin-points the problem as being sun associated. Although it's freezing that finalizes it.

If it was ambient temps involved, the damage would be to the entire trunk, or at least not so sun-side oriented.

I find sunscald to be very very rare in our area, but commonly blamed for sunburn, which is much more common around here when trees are planted wrong, pruned wrong, or removed at the wrong time of year.

Sunburn seems to be the leading cause of tree damage near Medford, Oregon. In one courtyard near the college where I taught tree care in 2006, had sunburn on 1 out of every 3 trees. A useful example within 2 blocks of the classroom.

 

[Gologit]

I live in orchard country, walnuts, plums, peaches etc. The guys I talked to said that it's mostly for looks now, especially up around the house or on property lines. Sun scald was also listed as a reason but mostly it's just a personal preference now. A couple of guys told me it also makes it easier for the birds to spot the bugs on the trunk.

 

[underwor]

Here we go again with that difference in terminology that used to frustrate Dr. Shigo so much. What I call frost cracks and sunscald are two different conditions entirely. Frost cracks usually occur in extremely cold weather, and are not limited on one side of a tree. Sunscald, which Dr. Shigo had a few thoughts on, almost always occurs on the SW side of the trunk. Alex did not say it was the warming and rapid cooling that was the entire cause of the trouble, but a trigger that accentuated the effects of pruning cuts (root and branch) and the disruption of the tree sap flow related to them. He thought the combination of the two led to the mortality of the cambium along the area with the resultant cupping followed by death and loss of the bark. I will try to attach a link to an image I took while working at WIU that shows the damage on the SW side of a young basswood (lime in Europe) and the juxtaposition of a couple of pruning cuts made at about planting time. These are just observations and some other things to think about.

The first image is what I call a frost crack, open at about -30F.
http://165.234.175.12/photos/Pathology/Frost crack.jpg

Here is the basswood/linden/lime/Tilia spp.
http://165.234.175.12/photos/Pathology/Linden sunscald before.jpg
and 2 years later, once rough (insulating) bark formed, there was no more injury(??)
http://165.234.175.12/photos/Pathology/Linden sunscald+2.jpg

 

[M.D. Vaden]

Sunscald, which Dr. Shigo had a few thoughts on, almost always occurs on the SW side of the trunk. Alex did not say it was the warming and rapid cooling that was the entire cause of the trouble, but a trigger that accentuated the effects of pruning cuts (root and branch) and the disruption of the tree sap flow related to them. He thought the combination of the two led to the mortality of the cambium along the area with the resultant cupping followed by death and loss of the bark.

Are you referring to frost cracks about the trigger part?

I figured that's what you meant, due to "sunscald" damage often seen on un-pruned young newly planted trees.

Interesting that you introduced the frost cracks, because that's even another one yet.

It's so much different from any other subject matter, like "cambium" where almost every resource is basically on the same page with the same definition.

Did you ever end up in a lecture where Dr. Shigo or another speaker had to invest a lot of time getting everybody on the same page for definition?

 

[lxt]

Here we go again with that difference in terminology that used to frustrate Dr. Shigo so much. What I call frost cracks and sunscald are two different conditions entirely. Frost cracks usually occur in extremely cold weather, and are not limited on one side of a tree. Sunscald, which Dr. Shigo had a few thoughts on, almost always occurs on the SW side of the trunk. Alex did not say it was the warming and rapid cooling that was the entire cause of the trouble, but a trigger that accentuated the effects of pruning cuts (root and branch) and the disruption of the tree sap flow related to them. He thought the combination of the two led to the mortality of the cambium along the area with the resultant cupping followed by death and loss of the bark. I will try to attach a link to an image I took while working at WIU that shows the damage on the SW side of a young basswood (lime in Europe) and the juxtaposition of a couple of pruning cuts made at about planting time. These are just observations and some other things to think about.

The first image is what I call a frost crack, open at about -30F.
http://165.234.175.12/photos/Pathology/Frost crack.jpg

Here is the basswood/linden/lime/Tilia spp.
http://165.234.175.12/photos/Pathology/Linden sunscald before.jpg
and 2 years later, once rough (insulating) bark formed, there was no more injury(??)
http://165.234.175.12/photos/Pathology/Linden sunscald+2.jpg

Good post!! as I refer to the causation & effect the same as you!! & you kinda reinforced what I was saying & what Ive been told!! sometimes its hard to convey things in their entirety, you did a good job!!

LXT...............

 

[lxt]

Are you referring to frost cracks about the trigger part?

I figured that's what you meant, due to "sunscald" damage often seen on un-pruned young newly planted trees.

Frost cracks about the trigger part................new terminology? this is how & why many get the wrong definition or multiple definitions, would love to hear "about the trigger part" defined arboriculturally!!

frost crack & sunscald are two different symptoms, there is no symbiotic relationship!! It is possible that one symptom could cause the other!!

You actually provide a service as a paid speaker? One could only imagine the made up :censored: BS you provide, you use key words(big ones to) & definitions in a way that some people who dont know any better might think you know what you`re talking about!!! Id feel guilty spewing out nonsense like you!!

M.D Id stick with taking & posting pic`s about the grove of titans!!!

LXT.............

 

[MadelineG]

White wash

So far I have find references to

Definitely use paint.

to Definitely not Use latex and to

Definitely use latex as well as to

Definitely not use paint

use lime or some formula with lime

and the reasons to do paint are myriad though often pooh-poohed.

 

[lxt]

So far I have find references to

Definitely use paint.

to Definitely not Use latex and to

Definitely use latex as well as to

Definitely not use paint

use lime or some formula with lime

and the reasons to do paint are myriad though often pooh-poohed.

I know, this is whats confusing to most people......so many different "opinions" & honestly thats what they are, funny years ago what was thought as good is today deemed as unnecessary/not so good, years from now Im sure the same will happen!!!

before I provide a treatment regiment; paint, chemicals, support sys, etc... I will usually consult with some one at the local college in the enviromental science field.............done this many times & is great help & honestly I think they like it as well ive often heard them say that not many people visit like I do!!! the point im making is check with someone(PHD) to get the good, bad & the ugly(pros/cons) pertaining to what you wanna do!!

LXT.............

 

[plumtree]

We whitewash the tree trunks of fruit trees with a paste of hydrated lime and water. We also use it on our grape vines.

It is used to help reduce pests and fungal problems on trees.

For some reason our area is troubled by 'Pear & Cherry Slug' and the whitewash treatment, along with wood ash spread under the tree line, eliminates this problem.

The other thing we do is tie strips of corrugated cardboard around the tree trunks to catch coddling moth larvae before they get on to do their damage.
Fruit fly traps are hung in the trees.

All this so the parrots can have a good feed!

 

[Ed Roland]

Plumtree, thats good stuff. And welcome to the site.

 

[kapow2826]

Plumtree,Thanks for sharing your insect control metnods. A conbination of corrugated cardboard and an insect parasitic nematode has been reported for the control of hybernating coddling moth larvae. This coddling moth nematode has been found in parasitised coddling moth larvae in humid invironmentsin in the U.S. and Mexico. It has been used suscessfuly to contol, carpenterworm, the medfly group,and pink bollworm. kapow 2826

 

[plumtree]

That sounds very interesting Kapow, thanks for the info, and it is a constant battle when you try to be 'organic'. We are not obsessive about being strictly organic but we are trying to grow food with high nutrient levels and at the same time we try to eliminate pesticides/chemicals as much as possible.

The methods we have outlined have been effective in reducing these problems but we find that it requires constant vigilance. My reference to the parrots highlights our biggest fruit pest. I don't want to divert the concept of this thread so I will start a new thread.

 

[kapow2826]

Plumtree.Yu might be interested in ,
safer soap for aphids, Bt. for caterpillers,
Steinerna reobravis.A heat tolerant insect parasitic nematode that worked in Phoenix in mid sunner soil applications for pink bollworm, control. Used in Florida for citrus root weavil control
B. bassiana is a fungus that combines an infective pathogen that produses a catagory 4 toxen when spores are added to water or when penitrating an insects skin. Honey bees are susceptible to it. If ylu dicide on this one be sure to read EPAs application derections and Susan Mahrs article
The Entomopathogen Beauveria bassiana Midwest Biologica Control News.

It is good to hear from you. kapow2826




fqloridq

 

[M.D. Vaden]

what are the ingredients of whitewash? CaCO3? sounds like a trunk drench of an essential micronutrients. Indians in california used to grind up oyster shells and make a paste to put on trees. I see a lot of sunscald and I think it makes a lot of sense for all the other reasons above too. re lenticels, i think gas will exchange through whitewash but less through latex/oil paint.

That's what came to mind as I was sifting through university websites compiling the article for Online Seminars for Municipal Arborists.

I've never come across a topic where there was so much difference between resources. It looks like an area that could use a nice piece of research to bring everyone to a concensus.

One of the sites, probably one of the links at the end of the article at Online Seminars, seemed to have a recipe for whitewash. May be the University of Colorado.

I don't like the painted look myself.

My preference leans toward a screen that is fastened in a way so as not to be against the bark.

Almost every information resource agreed that it was triggered by sun. But finalized by the cold And that a screen would help. Dr. Gilman wrote that there is little research to show that wraps are dependable. None of the resources had any comments contrary to a screen positioned so as not to touch or wrap the trunk.

It seems that the best option is for trained tree care professionals to use their own ingenuity and education, with materials in their area, to provide a screen that blocks the sun, but does not wrap the trunk.

Sunscald occurs around here, but it's quite uncommon. Usually it's sunburn from summer that people call sunscald, since the damage occurs on the same side basically.