I have a house that came with a line of Black Arborvitae (10' tall) on a property line with a close neighbor. It provides us with privacy for our terrace in the summer. Last winter was particularly severe here with snow, wind, unusual cold, etc., and everything suffered, including these. They thinned out considerably, some areas dying back, especially at the bottom which sheilded us from the neighbor's windows. I'm concerned that they will not fill out again at the lower/middle levels. Is there any way to encourage growth in the lower/mid areas? 4 years ago my arborist topped them saying it would strengthen the trunks, and had me remove the ties to stakes when they were planted. They were cutting into the trunks. The tops then became very dense. I'm afraid that any pruning will just make permanent holes in this natural 'fence.' I'd hate to have to replace them, but if necessary in the future, we will. We have open/part shade, and not too many things are good possibilities. I'm careful about shaking off heavy snows, etc. but last year when we were away we got ice and then snow, and they really suffered. Suggestions and advice would be very welcomed. This is a line about 50' long, and whatever goes there can't get too wide. Manhattan Euonomous are popular here, too, and I know they are very amenable to pruning. I'm on Long Island Sound, in a zone 6/7, perfect for my Japanes maple collection!
By black arborvitae I assume you mean Thuja occidentalis 'Nigra'. I'd like to hear an explanation from the "arborist" how topping was going to strengthen their trunks - or strengthen them in any other way. They were apparently damaged by weather conditions, on top of which - so to speak - they were then promptly decapitated, forcing them to draw on stored energy reserves to regrow new tops. Trees are living things, just like us. "A Tree Hurts, Too". If you wanted them to fill in, good cultivation (mulching, irrigation, whatever was required) would have been the direction to go in.
The arborist referred to them as black arborvitae. He did the topping 4 years ago, and the damage was last winter. I've been fertilizing and water when we had prolonged dry spells, but last summer was pretty wet. I guess my question now is whether with proper care, they can fill out again, or do they simply not grow that way. Looking at them through last growing season, I would think they do not.
Hi Jacquot: I think you will be better served to show us some pictures of your trees. I am not going to write that the trees will not produce growth in the areas where you want them to and I will not write that they cannot. I do know that with a serious hands on effort for a sustained period of time that you can help to initiate growth in the lower and middle parts of the tree but your work is cut out for you as it will take several years to bring these trees back, if it is possible for these trees. If it was just cold that hurt your trees we can deal with that but I suspect you had something else as your main culprit. The cold weather may have just enhanced the original damage that was done. I also would like to know why the trunks needed to be strengthened. Let's see some photos and perhaps some more information on the history of these trees as well as the your cultural practices since the damage so we can better assess a "game plan" for you. Jim
Thanks, Jim. I'll take some photos and post them. I've also had a contract with the arborist over the last 4 years to inspect and spray as needed during the season, and they had noted spider mites fairly regularly for these trees and sprayed for them. But it was after last winter that they seemed to suffer. I appreciate any advice for encouraging them. They were staked when planted, and my guess is they went in at about 5-6' tall. The arorist said to cut the ties, which were definitely cutting into the wood. Doing this made them more suceptible to bending in snow, and he recommended the topping saying it would strengthen the trunks against this. When we were away at Christmas '03, I came back to find many bent to the ground. I worked with them, and while they are straight again, but definitely not as full. I fertilized one year with stakes--which I have read since is not the best idea--and since then only with Hollytone, as recommended on the packaging. I am pretty careful not to over do it. I have hostas planted at the base of them, and run a soaker hose through them which I use as needed.
Sounds like they are rootbound. It is not normal for them to be falling over. Thin crowns + falling over might also indicate root rot, I suppose.
I was told, and have observed similar plants in the area that bend very easily with the weight of snow, that this is a problem with these trees. The trunks seem extemely flexible. I took a photo this morning that shows the thicker growth at the top, which took place after they were cut, and the thinner lower areas. The photo is a little dark, but shows the state of things. I hope the attachment comes through OK, as I don't see it in the preview.
I know about what snow can do to some of my Conifers at a higher elevation. Almost every year I lose a couple of Digger Pines that will lodge over almost prostrate to the ground. If I cannot adequately stake them to once again stand straight I have to cut them down. My Atlas Cedars for several years took a beating until I sturdily staked them. I'll be honest, I expected these to look worse. Sometimes in spite of ourselves or contrary to what we really wanted to accomplish we end up making the right decision. I think as a neighbor break (similar to a wind break but with neighbors we can get noise that we do not want to hear, sights we do not want to see and it give us, perhaps them also, more privacy) you did not really want these trees to become much taller than they already are. Generally, in ancient times when we would dead head or top a tree we wanted to encourage root growth as opposed to strengthen the trunks. For snow that will force these trees to lodge over, I guess the reasoning by the arborist was not so off base after all. Yes, the topping will force root production as well as making the trunks less pliable. It is extreme of us to have to do things in this manner but in some cases the effect it can create afterwards may be beneficial for us in the long run. As long as these trees were left alone then you would get height on them but at the expense of the middle and lower growth. Now that the size of these trees has been determined let's deal with the card hand we now have been dealt. Now, so much comes down to what you want for the shape to be of these trees. Do you want them to become a nice 8-10' hedge? Do you want to leave them like they are for size and shape? I will say that you will want to continue on a spray program for mites for a few years. Probably a spray for you there in late April, early May and if you get some discolored areas about August, another spray. I think another issue is how much hands on work can you do for these trees or do you plan to hire someone to manage these trees for you? I think a good cleaning up of the dead areas will help you and then you can decide what you want to do with these trees as they will not be a problem to block off the tops, square or round up the sides a little and then force them to either grow into each other to form a hedge or square them enough to let in air between them and wait for the middle areas to fill in. They will fill in once you block off the tops and keep them flat topped or round topped if you prefer for a while. I've had to that here for our Podocarpus gracilior. That is what the misses wanted and she is happy with the squared heads, full bodied, maintained look of her trees. I have to shear them with the hedge trimmers twice a year here to maintain the appearance she wants from them though as we get more growth spurts in a growing season than you will get where you are. There are pros and cons to whatever you decide. If you let them form to become a hedge you get more privacy but the trees will become tougher to get good coverage of the mite spray and if you ever get a fungus disease that hits the needles you will wish you did not have a hedge. You can square shape the trees which will be easier to spray, give more air to the trees which will lesson your insect infestation, cut down on the incidence of any needle fungus as well as keep the trees shapely and neat looking but you will be able to see your neighbors some through the uncovered spaces between the trees. Tell us what you want to do with these. If you do want the height kept under control plus help to fill in the middles you will not want to use fertilizers high in Nitrogen. A 10-20-20 or a 5-10-10 well watered in will be good enough in the Spring and a dose of 0-10-10 in early Fall. A fertilizer with about 6% Calcium and Sulfur would work well for these trees. Jim
First, thank you very much, Jim. I would prefer a hedge for maximum privacy, but the squared cut, which I assume means perhaps a foot or so of space between the trees, might work. I'm in an old neighborhood close to NYC and the yards are quite small. This is my only really close neighbor, and the people here before us put these in. I might have made another choice, but when these were full, they were beautiful. I can handle the remedial care myself and would enjoy it. I spend a lot of time in the garden on purpose. Fertilizing is not a problem, nor pruning, although the tops might have to be done by the arborist. I will definitely keep on a sraying program as I don't want to lose anything to insects or fungus. For pruning, do you mean cutting back to the trunk whatever is dead and let's say, in poor state of health? Will this regrow from old wood? If there are branches with some tip growth only, might they fill in, or would pruning back be good for that, too?
Well, the hedge would be my third option as it pretty much ruins the "look" of the trees. Having one foot spacings is not going to help all that much either. What I would want to know now is where on the trees do you want to see the most coverage, the middles or the lower portions as the lower portions may not ever come back for you? Even if you made a hedge out of these trees, the tops will be the same height and you will get some of the middles to grow back depending on how much light they will get (they will grow back some no matter but they may not come back in full to give your hedge better balance). I would not cut back to the trunk unless the branch is completely dead. Part of the problem you have with the lower branches is that most of them are some of the oldest wood on your tree. Now they are getting the least amount of sunlight and they will brown easier than in earlier years. If you want growth to come back to them you have to provide a means for them to get more sunlight, otherwise it may not matter what you do for cutting as they may not respond for you. The areas where you have tip growth and no growth in between on the branches is a judgement call. Do you cut the limbs halfway hoping you will get more growth to fill in or do you leave the limbs alone? Unless you provide more light to the lower extremities of the trees you may just be better to leave the limbs as they are. Continual cutting of the tops with some shaping of the sides will provide more sunlight to the lower portions of the tree. The signal we send to the tree when we prune the tops once or twice a year tells the rest of the tree to send out new growth. It is the tree that will tell itself to fill in the middles. The lowest portions of the tree will be the least likely to give rise to new growth. I would suggest you talk with your arborist and give him or her some ideas as to what you really want from these trees. It seems to me at this point that you would rather have a hedge for privacy than have the trees shaped to make them look all about the same, neat and manicured. If it were me I would opt for the trees to be cleaned up and shaped. The blocking of the trees would be my second choice and the hedge would be my last resort. Here is an analysis of your old situation. Actually with these trees prone to lodging your arborist did you a favor by cutting the tops of these. I've seen 75' tall bark beetle killed Ponderosa Pines fall right through cabins after a heavy snow. If you had let these trees get up to 40 feet tall whose house do you risk them hitting? Either way it is a loser for you. The tops look good to me as they are. I think a blocked off top and squared look will not do much for these trees. I like the rounded tops much better. I think a good cleaning of the dead areas and some pruning where these trees are growing into each other to give more light and more air movement is what I would do if the trees were mine. Talk things over with someone you have confidence in on the scene that can help give you ideas. Mention the hedge to your arborist as to initiate the hedge may mean that you will have to take a foot or more off the top. You are looking at no less than a 5 year project to clean up the trees, cut the tops every year and see how these trees will respond to your want to have them grow into each other and fill out. Then the maintenance of the hedge will require some time of you every year, sometimes twice a year just to square the front and back to make the hedge look neat. The sides are the least worry for shaping for a hedge at this point. If the hedge does not work out then you will want to go to the second option but once you start a yearly cutting of the tops it will take years for these trees to have the rounded tops again. Jim
Thanks again Jim. Perhaps I misunderstood the designations, I don't know. These are planted perhaps on 4' centers, so having individual trees separated does not seem like an option. I like the look of them as both individual naturally shaped trees, but they are also grown into each other, and hence a 'hedge.' I do not want a shaped regular rectangle block type hedge, even if properly tapered. I want something more natural, which is why we shaped the tops as we did the first time. I will ask a couple of arborists about them, the persons I have used and then their competitors here, who I've wanted to talk to anyway. If there is hope to have them become progressively better, I'm for it. If they are just going to get worse, that's something else, and I'd have to really think about what to do They get morning sun, that's about it. My house is a bit uphill, to the south east, as is my ancient White Oak. After mid day they get no direct sunlight, except very late oblique sun. Probably something with more resilient growth would have been better chosen, but I'm willing to give this a try. David
Hi David: If your photo is representative then you already have the equivalent of a hedge row of trees. The height of the trees has already been established. Now you would like more middle growth to fill these trees out more. For you to get more lower growth to cover up the windows of your neighbor will, more than likely, result in your having to cut the tops again probably down to about the lower roof level height of your neighbors house or lower. You will want to clean out the dead and browned areas in the middles as well as clean up the lower levels of each tree until in time the areas you want to have more growth start to do so. It may mean that each year you will have to cut the tops again. When we fertilize with any Nitrogen we can expect top growth which is not what your preference is. You want middle and lower growth on these trees. So, if you fertilize with any Nitrogen you have to force these trees to produce growth in the areas where you want them to, not where the trees will want to produce growth. You have to force the change in the trees growth habit to get what you want. You know how long it took for you to get the rounded heads on these trees after they were topped, so you should have an idea as to how long it will take to get your trees filled out, filled in and then you can start to leave them alone for a year or two prior to the next cleaning up. I think an ISA arborist that knows Conifers is the person you need to talk to. Give him or her an accurate estimation on what you want such as a hedge row as in the present case or a bona fide hedge in which the trees will all be cut down to about 5-6 feet tall or less, cleaned up and then we monitor the growth hoping these trees will respond to our desire for them to grow into each other. Yet at the same time produce more middle and lower growth. That can only be attained by cutting the tops often. I prefer hedge rows or a Conifer that will do what I want it to without a lot of maintenance but "green" does all the talking ("green talks, the rest walk") and if that is what the owner wants then it is our job to deliver as best we can unless their wishes are unrealistic and we are steadfast enough to tell them so. In your case of a hedge, I think your desire is realistic but to get the lower growth to come back in full is not so doable unless we really force the issue with these trees and then there is no guarantee what we want will come about to our or your satisfaction. The hard part will be getting adequate renewal of the lower growth, not the middles. In order to get more lower growth to shut out your seeing your neighbors windows then we almost have to start over from scratch with these trees. Even cutting the tops down to the height of the neighbors windows will not be out of bounds. Also, when we make the determination to create a hedge these trees will look much worse for a long while before they look any better than they are right now. Perhaps Paul, Ron B, Mario and Chris for some will either come back into this thread or come in now and share their ideas. They will not like the hedge issue as opposed to a hedge row any more than I do but if they've done it before they will know what I am trying to tell you. Jim
Yes, I'm starting to agree with that suggestion. I have one Yew, in fairly deep shade that is dense, lovely and large, but other varieties might be appropriate to the situation. I think some are more fastigiate, and I like the red berries, too. I have a little more time to decide which route to go. David
Yew rang Taxus x media 'Hicksii' probably the most available, 20' tall and comes in both male and female forms so if you like the berries you might want to select a female or a good slender fruiting cultivar like 'Flushing'. Some good things about Taxus are that they will do well in low light and can be maintained in a hedge form indefinately. 'Sentinalis' sounds good, 8' x 2'.