Hi everyone. I have a beautiful weeping blue atlas cedar in my garden in zone 8. It has quite a few brown needles on it (maybe 5% or the needles are brown). It's strange that the brown needles appear only sporadically. The needles on this tree grow in little "tufts" all along the branches, the dead needles will be one whole "tuft" on a branch with maybe 20 tufts that are uneffected. Also, the leader has brown needles for about 8 inches of its length. The tree is about 5.5 feet tall but has been trained in a zig-zag pattern so it may actually be quite old already. It has been in my garden only for 1.5 years. Could this be damage from the severe (for our zone) cold we had this past winter that is only showing up now (end of May, early June)? The tree has 3-5" new growth at the end of every branch so it seems fairly healthy, except the leader which has a good 8" of brown needles in a row, and the new growth on the leader (which is quite thin and fragile) is now very limp and looks like it's on it's way out. Any input would be appreciated.
Hi Zinzara: The "Blue Weeper" is the most susceptible to mite damage of any of the forms of Atlantic Cedar that I know of. In a Zone 8 we have to be mindful of mites coming in from wind blown, fugitive dust or from specific plants that are hosts for a variety of mites. Almond trees are notorious hosts for mites for example. Generally, the best cultural suppressant is overhead watering. One thing I do all the time for any of our Spruce (Picea abies, Picea glauca, Picea omorika, Picea orientalis, Picea pungens) also grown in a Zone 8, is give them a shower of water at least once every two weeks once the temps get over 90° just to keep the mites off of them. I have Cedrus atlantica 'Brevifolia' as well as Cedrus atlantica 'Glauca Aurea' growing at a 5,000' elevation and I can tell you it is not the cold that is causing the brown needles as I would see cold damage a lot with Glauca Aurea alone if that were true. It is possible that you have something else going on since I have no images to gauge things by but I know the plant and I know what damage the mites can do to us in a Zone 8. Another quick point is that when this Cedar is hit by mites the plant becomes less tolerable to high temps and the new growth can be severely affected in hot weather as a result. Jim
Thank you Mr. Shep Thank you so much for your help, it had occured to me that mites might be the cause. I will try your watering technique and hopefully that will make a difference.
Hi Zinzara: Public enemy number 1 on a Blue Weeper are borers that come in. They will make almost pin hole sized areas that will extrude a light amber colored ooze (sap) that will be visible if you look for it, usually just right above the graft. Overhead watering or a good shower will also suppress that insect as well but if enough borers hit the plant it will not survive for very long. Borers are the leading killer of the weeping Blue Atlas Cedars in a Zone 8. If the browning of the needles becomes worse, let me know. Jim
Is it possible that the pegs are broken from animals - like squirrels scampering around in the tree? Best wishes from "down under" in Oregon ( www.mdvaden.com ) from this Canadian born Oregonian.
Hi M. D. Vaden: < Is it possible that the pegs are broken from animals - like squirrels scampering around in the tree? > Yes, indeed that can happen. One gray squirrel in particular broke my central leader on my Cedrus atlantica 'Fastigiata'. At the time I saw it happen I was not happy but the squirrel ended up doing me a huge favor. Instead of having a tall "string bean" for a tree it later developed some girth around the middle and became a much more compact grower. I used to cringe every time I saw more than one squirrel in my 'Glauca Aurea' as I know some needles will be lost but the tree is large enough now to withstand the squirrels antic, most entertaining fun. Jim
Update on Blue Atlas Cedar Thank you all for your help. I am certain it is not squirrels doing the damage, as the tree doesn't lead anywhere and is too small to climb really. As far as borers are concerned, I have not been able to find any "pinholes" or sap oozing that would indicate their presence, I also have not found any mites (shaking the tree over white paper produced nothing but needles). I have taken to watering the tree hard from above at least twice a week. For a while, every day their seemed to be more and more brown needles, but now it's been a good 2 weeks since I've noticed any. I have removed all of the damaged needles. I had to cut the leader off as the whole thing was brown and limp, so I don't know what will happen with my tree now, though it seems healthy and all the new growth is growing along, turning blue (from its fresh green colour) and hardening off. It's seems ok. Overall, probably only 5% of the needles were affected. Incidentally, I was at Queen Elizabeth Park recently. They have a large, old, weeping blue atlas cedar in front of the restaurant there. It had exactly the same type of damage on it as mine (only much much worse). Thanks everyone for the help.
hi gang sorry for butting in! I'm going to jump off the fence and asume that Zin is in the lower fraser valley somewere. (due to reference of QE park) All the previous suggestions are Great. I Would just like add a few things that we ran into in Abbotsford. The complex had 25 of these rascals. Unfortunatley due my lack of Knowledge at the time we lost 7 of them. Aprox 18 trees were exhibiting signs as previously discribed. Turned out we were dealing with a variety of probs 1. mites 2. Black scale The above 2 where harboured in a hedge and the wild red cedars 3. Root weevil 4. Birds (feeces) check out the life cycle of these critters Regards Doug
Hi Zinzara: You've done what you needed to do to help this tree. Removal of the old, dead needles is quite important. The Mites that reside in the dead needles cannot be seen by the naked eye. The paper method may work on larger sized Mites but will not work on these as they do not brush off very easily. The shower method is the best solution that I've found. This time of year with the warmer temperatures I try to shower my Conifers at least once a week where I am. Hi Doug: Root Weevils can indeed be a problem where you are. Most of our Blue Weepers originated from Oregon and they can be laden with Click Beetle larvae. Every time I transplant an Oregon grown plant I see the critters. Are Root Weevils enough to kill the Cedar, no they aren't but in conjunction with a disease or a serious Scale outbreak they can help weaken the plant enough to kill it. I've read some reports of Root Weevils killing Conifers in the Pacific Northwest but I feel there was something else going on at the same time that led to the trees eventual death. We are too warm for Scale on our Blue Weepers here. I suppose that if we had Citrus around that had Black Scale that the Blue Weeper could become infested but I've not ever seen that happen as of yet. As a Citrus grower I know about Black Scale on Oranges. If we get any real Scale on our ornamentals it will be Oyster Scale and they will hide out in the shady parts of the tree or shrub, otherwise they will fry from the heat. We do get an occasional Cottony Cushion Scale outbreak that does invade some Conifers here though but usually only trees grown in dense shade. As far as bird feces that will depend on which birds, what they were feeding on and how much feces came in contact with the plant. Still, the number one killer for this Cedar for us here are Borers but a Mite infestation can weaken the tree enough for Borers to come in and kill it. Something else goes wrong before the Borers hit the trees is what I am saying. Jim
I posted this message last year when I had a minor problem with browning needles on my weeping blue atas cedar. We managed to control the problem with frequent overhead watering and the tree survived well. This spring it had a tonne of new growth and looked so well and healthy, unfortunately I was unable to watch it as closely as last year and in the space of a couple of weeks it went from green and healthy new growth the 70% dead needles and is now in a state of impending death I'm afraid. Does anyone have any idea if it's even worth trying to save, or if I should just say goodbye?
Re: Thank you Mr. Shep I will try the watering method also.However,will water alone rid my trees of these mites??We are cooling down from 110 degree temps.Please help.thx,jo
Hi Jo: No, the water alone will not keep the mites off your tree but in warm to hot weather the overhead watering or hose sprayings of "jets" of water can knock many mites off the tree that may not come back. I like to spray them with water for three reasons, one, to knock dust off the tree as the mites like to attach themselves to a dusty and/or a dry needle, two, I like the idea that if I liberate them, expose them into the hot air, then I can force a disruption of their life cycle and three, I do not like to use a chemical spray for mites in hot weather. If we use a spray such as Sevin or Diazinon one application in hot weather may not be adequate, no matter what kind of coverage we get with the spray. We may have to use a second spray about a week later for a heavy infestation of this insect. I use a chemical spray only if I have to. I suggest you read this IPM report on Spider Mites from the link below. http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7405.html Jim
There is also, in my understanding, a fungal disease that can cause this brown needle pattern on Cedrus atlantica. I can't remember what the specific disease is, but was told about by Don Howse, a conifer specialist in Oregon (past president of the ACS). He did say that the weeping blue atlas seemed to be the most susceptible to this infection.
I have had almost the same problem as described. It started about 4 years ago and the tree is over 20 years old. Early spring about begining of May the tree has lots of new green growth. By the end of May 80% of the new growth turns brown in about a week and some of the brown spreads into the older growth. Weather is cool and rainy and damp at this time and past years I tried spraying with water but it does not help. I have been told this is not mites but a fungal disease. I was told you have to spray around early April or it is too late to stop that season. Every year my tree has gotten worse. I thought it was gone this year since mid May the tree looked great but withing one week it was over 50% brown. Just like the past years mid June as the area drys out, the new growth is coming back. I keep cutting out the dead area and removing the dead needle buildup but still have not had any luck controling the problem. :(
This seems to occur just as the new growth is emerging. I've been told that it's mites, but have never seen any. If allowed to continue there's lots of damage, but the tree recovers. I've found that spraying with Benomyl, 30cc powder to 3l. water, as soon as the new growth emerges seems to control the problem.
