Time for Annual Bashing of Christmas Trees

It's October -- time for Halloween, Christmas decorations to pop up in stores, and the annual bashing of real Christmas trees. Thought I'd share the following that I sent in to a blog connected with artificial trees praising them as the environmental choice.

"...there is no reason why the joy associated with the Christmas evergreen may not be a means of arousing in the minds of children an appreciation of the beauty and usefulness of trees; and keen appreciation of the beauty and usefulness of trees is a long step toward the will to plant and care for them (Arthur Sowder, US Forest Service, 1949)."

A Christmas tree is a celebration of life -- renewed life in the dead of winter -- renewed life because of the birth of a Savior. How can that be celebrated with a big plastic brush? Because that's all an artificial tree is no matter how lifelike. It's not a tree. It never provided a perch for a butterfly or protection for a bird from a summer storm. It was never brushed by a deer or bear as they walked by. It never felt the pull of the sun to make it break bud and grow. It was never alive as a real tree was.

So what if you cut it down? Another will be planted in its place. That's the circle of life, after all. If people really wanted to be environmentally conscious at Christmas there would be no lights, no presents, no feasts, no visits to family. Cutting down one tree at Christmas is nothing compared to the trees cut down to supply an average home's paper needs for the year. But a real tree becomes part of the family if only for a few weeks. And after the season is over, it can be recycled into mulch to provide protection to new plants in the spring.

Don't we have enough plastic from China already in our lives? Shouldn't a really great Christmas have a real tree?

So yes, Virginia. It's OK to use a real tree to wait for Santa on Christmas Eve. It will make the Jolly Old Elf smile to himself to think that not all the traditions of yesteryear have not been forgotten.

A Word About Spray Suits

Lots of folks wear the basic disposable Tyvek coveralls when applying pesticides. These state that they are not water proof, yet lots of folks use them when applying not just dry pesticide formulations, but wet formulations and even high pressure sprayers.

On Friday, Jerry Moody and I applied some materials for fall control of algae. We don't think they will work, but we wanted to be sure. One thing that some growers are doing is spraying bleach on trees to clean them up. We tried that last year, but with a backpack mistblower. This year we tried it with a high pressure sprayer to see if that will work any better since it didn't work at all last year. I sprayed a 3% solution of bleach on about 30 large trees with a high pressure sprayer, doing a thorough job of coverage. I wore a white tyvek suit.

Well, look at my shirt at the end of the job. My purple shirt was bleached where the zipper on the Tyvek suit was. If it had been a pesticide, I would not have been protected from it.

Take home message? When spraying with a high pressure sprayer, you need something water proof.

We'll let you know in a couple of weeks what kind of algae control we got.

(And I liked that shirt too!)

Cryptomeria Scale Found in Ashe County

A small field of trees in West Jefferson has what I think is Cryptomeria scale. I had samples sent to the Plant Disease and Insect Clinic in Raleigh to confirm it, but it definitely looks like the same thing we saw in Macon County earlier this summer.

There are several differences between Cryptomeria scale and elongate hemlock scale. First of all, there are more symptoms of yellow blotches on the needles. Most of the trees with Cryptomeria scale have these symptoms, whereas most trees with EHS have no yellow discoloration.

A close-up of the foliage shows the striking symptoms. Note how it is worse at the lower part of the shoot where more scales have settled.

The scales look quite different from EHS. The newest growth appears to have mostly nymphs or younger scales. They look almost like yellow dimples on the needles. They also reminded me of eggs cooked sunny side up with really big yolks!

Under the microscope you can see that even the young scales hide themselves under the cuticle on the needle, giving them protection, and making them harder to see. I guess that's what gives the appearance of a big yolk with a bit a white around it when seen through a hand lens. There are also some more mature scales in this shot at the top. They look bigger of course.

On the older growth, the scales seem to grow on top of each other. There are more mature scales. They look sort of round, and many look brownish, but those, I think have already died. The healthy scales are yellow when you look at them under the microscope.

Many of these scales have been fed on by the twice stabbed lady beetles. These were everywhere on the trees, just like they were in Macon County. They left holes in the scales.

The adult lady beetles feed on the scales as well as the larvae.

Here are some lady beetle larvae. There are so many larvae, they almost look like they are feeding on and damaging the trees. But they are feeding on the scales. However, there are so many scales, they don't destroy them all. I looked at some needles under the microscope where the lady beetles had obviously been feeding, and there were live scales with eggs still underneath dead scales which had been fed on.

Here are two adults with eggs and some crawlers. It was hard to get a good picture of the crawlers as they were moving around a lot. But basically, crawlers all look about alike.

A scale that hasn't yet produced eggs was flipped over for this photo. The thin coppery line going from the middle of the scale is the feeding tube. You can see it best against the green of the needle at the top and middle of the scale.









These trees really went down hill over the last month. The grower didn't notice anything wrong with his trees until recently. In fact they thought that it was worse today than it was just last week. And in reports from other states indicate that the scale builds up and spreads very quickly. Its also been very dry in Jefferson this summer which I'm sure helped the symptoms be worse.

These trees are in a residential area with houses all around. As with the other site in Macon County, the best explanation as to why Cryptomeria scale showed up is because someone purchased nursery plants from up north where this scale is much more common, and they moved into the Frasers. Cryptomeria scale feeds on many types of conifers, but it certainly seems to like Fraser fir.

The grower is going to spray these trees within a week with Dimethoate, Asana and Safari. Before spraying, they will cut out and destroy the worst trees. In fact, it would take at least a couple of years of good growth to cover up heavily damaged. trees. I thought it best to add the Safari on an experimental basis as research from other states indicates that Safari works well.

It's getting a bit late in the season to control these scales, but hopefully they will get some control. I'll assess them after a month to see how well the treatment worked and probably again in the spring. If need be, the grower plans to treat again in the spring.

Are there more sites with Cryptomeria scale in western North Carolina? It is certainly possible. Most growers now know what EHS looks like, but they could easily mistake this scale for EHS. It does look different, however. It is more rounded that elongated. There are also no white males, and no white waxy discoloration on the top of the needles. Another tell-tale sign are all the twice stabbed lady beetles which appear to be very characteristic of this scale.

This scale is much worse than EHS. It appears that it spreads faster, and it definitely has a greater effect on the tree. We have yet to see if it is just as hard or even harder to control. According to reports from Pennsylvania and Connecticut, control of both scales is similar.

If anyone thinks they have Cryptomeria scale, please let me know and I'll come out and look at it. Everyone needs to keep an eye out for this pest, so we can track if it is spreading.

Algae Control Results

Several people have been concerned about algae again this year. However, I don't think the algae has been as bad this year as last year. In the two fields where we treated, there was definitely more of it on the 2008 growth than the 2009. We had a hot, dry spell in the summer that no doubt reduced the development of algae, but there are still problems. (Photo was taken by Bryan Davis last year showing extreme discoloration in 2009. Note that the current year's needles are not affected).

The first thing to realize when looking at algae control is that the best you can do is prevent more algae from developing. It's hard to cure algae once it's already there. It develops primarily on last year's foliage -- not this year's. It appears that it comes in the June time-frame. Therefore in these spray trials, we were looking at algae development on last year's growth -- that is 2009 growth. For the most part, we didn't do anything to reduce discoloration on 2008 growth (which developed the summer of 2009) or earlier. Still, if you can go to market with 2 years of good green color, it should be good enough.

This photo was taken under a microscope showing some algae on the needles. It is easy to see with a hand lens. It is also easy to wipe off the surface of the needle.

We applied different materials for algae control this spring before bud break at 2 sites -- one in Mitchell and one in Avery. Thanks to Jeff Vance and Jerry Moody for help in finding locations to work in and spraying the materials.

All applications were made with a backpack mistblower. At both sites, an untreated row was left between each treated row to reduce cross contamination of treatments.

At the Mitchell County site, treatments were made on rows of 10 trees. There were 3 replications. Applications were made on April 29 using one of the following materials:

1. Kocide 3000 at 3.5 pound per acre. This is a copper based material which is made up of 30% copper. Kocide label.
2. Dithane at 1.5 pounds per acre. The active ingredient of Dithane is mancozeb. Some Jackson county growers were seeing some control of algae in the fall when this material was applied. However last year, I didn't see very good results from this. Review of last year's work.
3. Daconil at 3 pints per acre. The active ingredient of daconil is chlorothalonil.

In Avery County we didn't replicate, but instead treated a long row with 30 or more trees. Original treatments were made on May 5 using either Kocide, Dithane or Daconil at the treatment rates described above. Addition treatments were as follows:

1. Cosan, an organic disinfectant, at 2 teaspoons per gallon
2. SA-20 disinfectant at 2 teaspoons per gallon. This product is made of 10% dimethyl benzylammonium chloride and 10% dimethyl ethybenzyl ammonium chloride. It is used to disinfect pots, greenhouse areas and tools.
3. Kocide applied twice -- on May 5 and again on May 19
4. Kocide applied once on May 19

Jerry, Doug Hundley and I looked at the Avery County treatments yesterday, and Jeff Vance and I looked at the Mitchell County treatments this morning.

There appeared to be more algae developed at the Avery than the Mitchell County site. This surprised me as the Mitchell County site was much worse last year. (This photo, taken in Mitchell County, shows a shoot from an untreated tree with algae on last year's growth).

All treatments appeared to have some effect on the algae. The Dithane and Daconil didn't work as well as the other products. Kocide appeared to work best. Applying it twice seemed to work a bit better, and applying it later in May also seemed to work some better.

This photo is of a shoot from a treated tree. Note that there is no discoloration on 2010 or 2009 growth. If the treatment hadn't worked, you would see discoloration on 2009 growth. The material didn't reduce the discoloration already present on 2008 growth. 

This is typical of any fungicide. They prevent disease from developing. They don't cure disease. Therefore a successful treatment will keep algae from developing the year it is applied. But that's similar to all of our pests. When you treat for twig aphids or spider mites, you don't do away with the damage you already have. Instead you cover it up with new, undamaged foliage.

I would like to repeat this next year, applying materials with either a high pressure sprayer or backpack mistblower. I suspect that the high pressure sprayer will give better control, but that most growers will prefer the speed of the mistblower. I also hope to try out some Kocide this fall to see if it will help "cure" some of the algae. I don't think it will, but since I didn't try it last year, I want to make sure. 

Take home message: It looks as if Kocide and perhaps some other materials will reduce and in some instances prevent algae from developing when applied in the spring. In fields where algae development is expected because of woods or the trees are growing close together, a preventative treatment is required starting the year before sale and continuing until all the trees are harvested.

A big thanks goes to Kelly Ivors and Gary Chastagner for their help in identifying possible treatment windows and materials.

Some HWA Pics

OK, I know this is a Fraser fir IPM blog. But I work some with HWA on hemlocks and can't help but post a few things about that too.

Five years ago, I took some photos of hemlocks in the Linville area. Today I went back and visited some of those trees. Mostly the hedges looked really good. But many of the trees that I know had been treated are now gone. Others don't look much better.

Here are the pictures:

This picture was taken five years ago.

This is the same tree five years later. It is still hanging on, but doesn't look much better.

This tree is no longer there. It had been treated with Merit, but didn't seem to be doing too well five years ago when this picture was taken.

These trees are in the same yard as the previous picture. They don't look that good either, but are at least still alive. The hedge, however, looks great.

My last photo is dead hemlocks along the Parkway.

2010 Growth in Organic Demonstration.

Today I measured the terminal growth on the 183 trees I've been evaluating at the organic demonstration in Alleghany County. Thanks again to Della and all the Deals and Tuckers for all their help with this study.

A big thanks also goes to Bryan Davis who has been keeping the site going. For the 3rd NCTA farm tour on August 14, Bryan dug up three trees from this demonstration so that folks could see how the trees were doing. One was a typical "late organic." Remember that these are the trees that are being grown conventionally until the last 3 years before harvest when they will go totally organic -- that is, they are "going organic" late in the rotation with just enough time to be certified as organic. He also brought 2 trees from the organic portion -- one that was growing poorly and one that was growing well.

Those trees were strikingly different. The poor organic tree was just barely alive. The good growing organic tree was growing well, until you compared it to the typical "late organic" tree which was taller and fuller.

The numbers I collected today with the help of my daughter (in the rain no less) bare this out. I measured the terminal of the trees and also gave the trees a rating based on how well they were growing. Trees were given a rating of "1" if they were barely growing at all. A "2" rating was given to a tree that was growing better, but still had poor color and bud set. A "3" rating was given to a tree that was growing acceptably. A "4" rating was given to an exception tree both in color, bud set, needle length and fullness. Of course these ratings were completely subjective and sometimes I had trouble deciding between a "2" and a "3" or a "3" and a "4."

Here is a summary of the data. The "late organic" trees are more likely to have a rating of 3 or 4. Their terminal growth is on average 4.6 inches longer, and there is a higher percentage of trees with at least 12 inch terminals.

There are some very nice looking organic trees. There just aren't as many as in the other section. Still, all the trees are growing better than they did last year. Last year the average terminal growth for the entire study was 6.1 inches. This year it was 14.0 inches -- more than twice as much. The trees that suffered severe drought when they were planted in 2008 with a southern exposure are finally growing strong.

NCTA Meeting

Hope everyone can come to the National Christmas Tree Association annual meeting in Winston this week.

I will be speaking on Friday morning. My talk is called, "Getting Personal With Pests." We have it on-line if you'd like to look at it. It is found at: http://www.ces.ncsu.edu/fletcher/programs/xmas/production-mountains/Sidebottom-Pests_2010-08-13.pdf

It's kind of a big file, so it will take awhile to pull up.

I'll also be on two of the farm tours. I'll be speaking on Saturday morning at Harry Yates' farm on elongate hemlock scale. Then in the afternoon I'll be speaking at Omni farm on scouting, pest control and our organic demonstration.