Almstead Tree & Shrub Care Blog

Thursday, February 28, 2013

Pruning Cane Plants


Now is the perfect time to get out your pruning shears and attack your rose bushes! Although it seems like winter still stretches out interminably before us, spring is actually approaching. Now, just as plants begin to break their dormancy and their buds are beginning to swell, is the time to prune most cane plants. Regular pruning promotes healthy growth and lush flowering in cane plants.

Many of our flowering shrubs can be categorized as “cane plants.” These plants continue to send up new shoots from their bases, where they typically have formed a clump. Roses and forsythia are our most common examples; the group also includes bamboo, kerria, weigela and deutzia among others.

Before you reach for your pruning shears, there is an important first step: take a good look at your shrub. What do you see? Are there dead canes? Even in winter, dead canes will appear different from live ones: they will look shriveled and blackened.  These will be the first things to prune away. 
Now take a longer look and envision how you would like your plant to ultimately look.  Forsythia, like many cane plants, has a gently weeping shape. Pruning should enhance the beauty of this shape. Although clipping forsythia into a hedge is fairly common, it does not highlight the beauty of the plant. I recommend putting down the hedge clippers in favor of pruning shears.

In general, we prune cane plants by removing the canes close to the ground. When we prune, we are actually helping the plant by “de-cluttering” it.  Old canes often give the shrub a stiff structure, rather than a graceful form. Removing canes that are touching or crossing will open up the plant visually and allow for air flow as well, helping to prevent disease. We are also helping to keep the plant at the size we want – rather than the 10 or 15 ft. in height it might want to achieve on its own!

The actual process of pruning isn’t difficult. Using CLEAN pruning shears or loppers, get down close to the ground and remove the dead canes, along with any puny or diseased ones. Then remove the canes you’ve identified that are cluttering the plant.  If you have a bush that hasn’t been regularly pruned, you may wind up removing a major portion of the plant.  If you prune annually, removing about 1/8 to ¼ of the plant is typical.

If you are pruning an older plant, especially one that hasn’t been recently pruned, you may need to use a small pruning saw to remove some of the old wood in the center of the plant. This can be a challenge (especially on thorny rose bushes), but it will improve the appearance and health of your plants. These old, hardened canes often clutter up the center of the shrub, and flower very little.
Most canes don’t flower in the first year (roses are the exception here). Forsythia, for example, will not flower on new wood; they begin flowering the second year, then they flower profusely for a few years and start to slack off. This is true for some climbing roses as well. Removing older canes regularly and encouraging younger canes to grow will maximize the flower production on your bush. Also prune away the ends that are touching the ground: on a vigorous bush like forsythia, they’ll root, causing an unruly clump.

The guidelines above work for roses as well. For hybrid tea roses (the most common roses in our gardens), we also prune back the individual canes.  Leave only strong branches on roses, and prune so that they are growing outward; cut at a 45° angle just above a bud facing outward.  Roses are prone to fungal diseases and adequate air flow will help keep them healthy.

You should also prune away any suckers on your rose bushes. Suckers are shoots coming out from the roots; they are common in grafted plants such as older roses.  Uncover the sucker with a trowel and nip it away where it meets the roots.

One of the great things about cane plants is their vigor: they’re hard to kill. If you’re overenthusiastic in your pruning, you may lose a season of bloom, but they’ll likely come back stronger and better next year.

For more detail on pruning roses, click here.   For forsythia and similar shrub pruning, here is a video with more information.

Wednesday, February 20, 2013

Salted Evergreens

This pine tree shows damage on its
eastern side.

Fallen trees have been removed, power has been restored, and people are back in their homes. For those of us in Westchester County, the effects of Hurricane Sandy have passed. Or not.

Since mid-November, I have been seeing an unusual level of salt damage to evergreens. While winter road salt always has a bad effect on many evergreens, the damage I’ve noticed recently is far more extensive. One of the effects of Hurricane Sandy was to carry salt spray from the ocean and drop it throughout our area. The northeast winds gave many of our shrubs a thorough drenching of salt water. Throughout the towns bordering Long Island Sound, we have been seeing extensive salt damage, particularly on the northeastern and eastern facing sides of evergreens. Many white pines that were near the ocean are entirely brown and desiccated on their eastern sides. This is true of plants several miles inland as well.

These Cypress trees received too much salt on their east side.
How can you tell if your evergreens have experienced salt damage? Take a look. If the plant or tree was green last fall and now has browning needles and dry tips, salt is a likely culprit. When salt coats the foliage of a plant, it draws moisture out, causing a burned effect.  Warming temperatures after the storm can also have this effect. If damage is extensive, the plant will die. If the buds are brittle or broken and easily snap with light pressure, the entire branch is probably dead. Once needles are brown, they never return to green again. However, I caution people to wait until spring before making any decision on removing the plant. This type of damage is new to us, so we don’t have a clear idea of how the plants will rebound.

Is there any way to restore a damaged evergreen? Maybe.  If green needles are mixed in with the brown, cross your fingers  and hope that the plant will rebound on its own. If the plant is heavily desiccated, including the buds, we can go back into the canopy and feather prune to where we find green cambium. This is labor intensive, but it can force the dormant lateral buds to grow out. Not all evergreens can be forced this way; there’s little we can do to assist plants such as hemlocks or others that won’t respond well to severe pruning.

I usually recommend several applications of anti-desiccant spray to broad-leaf evergreens during the winter; it can also help needled evergreens retain moisture.  I find it makes a big difference in our area, not just for salt burn but for winter burn in general. The freeze-thaw cycle that we go through in the New York Metro region is extremely tough on evergreens. (Does 5° one week and 45° the next week sound familiar?) A plant health care professional (such as Almstead) can take care of this; they will have the equipment to reach tall shrubs. If you apply the anti-desiccant yourself, make sure it’s on a day when the temperature is above freezing. Also, be aware that certain anti-desiccants should not be used on some evergreens such as cypress, arborvitae, cedar or juniper. Read the label and know the species of plant you are treating: conifer leaves can be broad-leaf, needle, scale-leaf or awl-like, and can’t all be treated the same way.

Salt in the ground is a different problem. Since Hurricane Sandy gave us a one-time application, any salt in the soil should dilute with the spring rains and snow melt. You may want to delay fertilizing this spring if you use a generic, synthetic fertilizer. This type of fertilizer contains salt; hold off until we’ve had some thorough soaking. Organic humates will bind the salt in the soil; there are actually products designed for this type of soil, geared to areas that experience seasonal flooding.

A sudden salt drench from a hurricane is unanticipated. If, however, you live near the water (or near a heavily salted road), choosing salt-tolerant plants is wise. Some plants, such as black pine, blue spruce and Chinese juniper will tolerate a lot of salt. I always recommend choosing plants that are comfortable in your location rather than trying to maintain a plant outside its natural environment.

Wednesday, February 13, 2013

Recycling Cypress


One of my favorite places to work – and to visit --  is WaveHill, the public garden and cultural center in the Bronx. This beautifully designed park is a garden for all seasons. Visiting there should be on every New Yorker’s to-do list.
Almstead removes trees at Wave Hill.
Work begins taking down these 35-40 ft.cypress trees.

We were recently asked to replace several cypress trees in one of their gardens. The trees had grown too large for their location and needed to be removed. 4 foot tall replacement trees had been nurtured on-site, grown from cuttings of the mature cypresses to be removed.  The smaller trees will look more proportionate to the rest of the garden and not obscure the view of the Palisades.

This job was different from most of our tree removal because we were asked to take down the trees in as large sections as possible.  Unlike in forestry, where trees are often cut for lumber, in urban forestry we typically take down trees in 2-4 ft. sections: we don’t often have the room to drop an entire tree; also the smaller, cut sections are easier to manage through tight spaces and into the chipper. However, since cypress is an unusually valuable tree, the trunks would be taken to the woodworking shop facilities at Wave Hill where they will eventually be used in one of their upcoming projects.

I’d like to digress for a moment on the history of cypress trees. Cypresses have been admired and ultilized for thousands of years. They are an old-world Mediterranean tree, whose tall, narrow beauty was used to grace important public and religious sites. The wood was also valued for its lightness, strength and lack of sap. Ancient Egyptians used cypress to make coffins for their mummies; Plato inscribed his code of laws on cypress because he thought it would last longer than brass.

Today, cypress remains a valued wood for its resistance to rot, lack of warping and the beauty of its grain and hue. America has many native cypresses.  The ones at Wave Hill are Lawson Falsecypress (Chamaecyparis lawsoniana).  Though called a “false” cypress, the genus is generally considered part of the cypress family.

Here are some photos from the job:


Almstead crew removes trees at Wave Hill.
We began by limbing up the tree by removing small branching

Almstead crew removes trees at Wave Hill.
Then we rigged the bare trunks by anchoring 
them with a line to another tree. 

Almstead crew removes trees at Wave Hill.
We felled the last trunk by steadying it with
 ropes from the ground, 
allowing a slow, controlled progression to the ground.

Almstead crew removes trees at Wave Hill.
Wave Hill wound up with some beautiful cypress logs, up to 20 ft. in length.
Ken Almstead, CEO and Arborist

Tuesday, February 5, 2013

Tree Removal Panic

Source: Joseph O'Brien, USDA Forest Service, Bugwood.org

No one wants a tree falling on their house. As we all know, Hurricane Sandy brought down thousands of trees throughout our region, causing extensive damage to property. Many people are now looking at the trees surrounding their homes and wondering which will be the next to go. At a recent meeting of Almstead arborists we found ourselves discussing a new phenomenon: Tree Removal Panic.

Over the last few months, we’ve had many calls to remove healthy trees. Sometimes the tree’s owner is concerned about the potential damage of the tree falling, other times neighbors feel threatened by a tree and are lobbying for removal. How do you decide how risky a tree is?

The first thing to remember when you look at your trees is: these trees already survived Sandy. Hurricane winds provided a stress test for trees which many failed; the ones that survived have proven their resilience. Nevertheless, it’s best not to take the health of a tree for granted, especially a large tree that could do damage if it fails. An arborist can evaluate the condition of your trees by inspecting them for signs of disease or decay; we call this a “Tree Risk Assessment.”   Trees don’t need to be completely disease-free in order to be stable; it’s important to evaluate the amount of damage inside the tree as well as the location of any weakness. In some situations, we actually “look inside” the tree by using an instrument called a Resistograph. By boring tiny holes into the trunk, we get a map of the amount of decay inside. We are able to evaluate the level of risk associated with the tree based on this knowledge.

Armed with the knowledge gained from an arborist, the decision to keep or remove a tree is ultimately yours. It’s a question of how much risk you are willing to take. No arborist will guarantee a tree against failure, any more than a doctor will guarantee that your health will remain perfect. We each have to determine the level of risk we’re comfortable with, and weigh the pros and cons. Trees serve many purposes: they offer shade and keep our homes cool in summer; they provide habitats for songbirds and animals; they screen us from neighbors or eyesores; and they are immensely beautiful. They also protect us in many ways. Though a tree may fall on your roof in a hurricane, it may also shelter your home from your neighbor’s falling tree – or his airborne lawn chair. It is up to each of us to decide the cost/benefit balance for keeping a tree.

It’s also important to remember that falling branches are more common that falling trees. Judicious pruning can substantially reduce the likelihood of branch failure. Finally, be aware that many communities have local ordinances that prohibit removing healthy trees from private property. If your tree is at risk of failure, an arborist can help document the reason for removal and get the permit from your local government.

I sometimes ask my clients, “Can you experience the experience?”  In other words, if a tree were to fall on your house, would it be unendurable or worth the risk? How large is the tree? What would it fall on? A huge tree poised over your child’s bedroom is a different situation than one that might land on your garage.

As in other areas of our lives, we each have a comfort zone with regard to risk. For most of us, the small risk associated with being surrounded by healthy trees is outweighed by the joy they bring us.