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Apple Trees
We're going to plant some apple trees in the spring and my husband's father is insisting that we train them by pruning and tying. What is he talking about?
It sounds like your father-in-law has some experience with apple orchards. Training of newly planted apple trees is done to open up the crown and keep it open to the sun and as well as to train branches to grow one way by tying and pruning off poorly developed branches to force new shoots. This is done until the crown has attained its final size and shape. Excess shoots are removed to encourage fruit-bearing branches to develop. After all of this there are the rejuvenating cuts and thinning cuts necessary to keep the tree in shape in later years.

All shoots need as much sunlight as possible to keep them growing properly (that is, up) and by tying the tips to the main trunk it forces horizontal growth. This will make the tree bear fruit earlier than one that was left to grow on its own. Any shoots that grow on the bottoms of these branches are pruned off. Branches that have been severely pruned form strong fruit- bearing shoots.

After four years or so, fruit-bearing wood, which wants to point downward, is cut off at a point that makes a new shoot. This new shoot will soon bear fruit and hang downward like the one that was severed. This is a continuous process but the yields of apples are high and these trees tend to have few problems with disease.

I was told that the holes at the bottom of my apples trees are made by the apple tree borer. How can I get rid of them?
There are two apple tree borers: the roundheaded Saperda candida and the flatheaded Chrysobothris femorata. The larvae of these species have slightly different life cycles but both can damage a tree severely by boring into the sapwood and the heartwood. One thing you can do: using a flexible wire, poke into the boring holes and stab the larvae. As a deterrent, you can paint the bottom two or three feet of the tree, including an inch or so below the soil line, with white latex paint that has been diluted with an equal amount of water. Scrape away the soil carefully before painting and then replace it. The latex hinders the female beetle from laying her eggs in the bark crevices. You can also wrap the tree with burlap, or even paper, to prevent attacks. If the tree was attacked, prune away any badly damaged limbs. Attacks by the borers weaken the tree and make it susceptible to other insects or disease problems. Chemical controls are not very affective against borers.
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Arborvitae
Some arborvitae were planted along our driveway two years ago, when the house was built. A couple of them are turning brown, starting with the bottom branches and moving up the tree. They also have bare branches and the wood is not firm. We can find no insects on them. Do you have any idea what is happening?
If you see no signs of insects and the dying starts at the bottom, chances are there's a problem within the root system. Try removing one that is turning brown and see what the root system looks like. If you can't do this yourself call an arborist for help.

If the roots look like they are dying there are a number of things to consider. One is that the tree was planted too deeply; trees should only be planted as deep as the root ball. Another possibility is that there was burlap around the roots when the tree was planted and it is not the type that disintegrates or perhaps the root ball was enclosed in a wire cage that is still in place. In these cases, roots will grow in circles around themselves instead of spreading out. Another cause of death to arborvitae is wet roots…they don't like wet feet.
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Birch
What kind of birches to best in southern RI?
River birch (Betula nigra), is the best unless you are willing to battle the birch borer or the birch leaf miner. This birch is widely adapted throughout the southern, Midwestern, and eastern parts of this country and grows wild along riverbanks. It also does very well in flooded areas. It needs water and will become stressed when it cannot get its roots into a moist soil. When the tree is young the bark is red but gradually becomes shaggy and finally becomes chocolate-brown.

Paper birch (B. papyrifera) and the European white birch (B. pendula) are very prone to borer and leaf miner damage unless grown in the colder regions of New England or elsewhere.
Monarch birch (B. maximowicziana), native to Japan, is a large, fast growing birch with big leaves and catkins. It is tolerant of both cold and wind and will grow on dry sites as long as there is good drainage. Once the tree is mature, the bark peels and hangs from the trunk giving it added character.
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Birch Pruning
We need to remove a spire from our white birch clump and opted to do so this winter because of the borer and other insect problems. I recently read that white birches bleed heavily if pruned past mid winter. What should we do?
Birches should be pruned in mid to late summer because of sap bleeding. It can even be done in early fall. Bleeding weakens the trees, making them susceptible to insect infestation and/or other diseases. Once the spire has been removed, keep an eye on the wound until it heals over. There is no need to paint it or apply any insecticide. You may have new shoots coming up from the roots around this area which may have to be removed to avoid crowding.
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Black Tupelo
There's a rather tall tree in our woods that has little dark blue or blackish berries in the fall. We were told it's a pepper tree but I can't find any information about it.
It is probably black tupelo (Nyssa sylvatica), also called blackgum or pepperidge tree. This tree will get to around 60 feet in our area and perhaps 2 feet around. It is a lovely tree with leaves that are shiny on top and pale green and somewhat fuzzy underneath. The flowers, which appear in spring, are green and often are missed as they blend with emerging leaves. The male and female flowers, by the way, are on different trees so there must be another tupelo close by. Your description of blue to blackish berries was perfect. Wildlife love those berries and the flowers are a good source of pollen for honeybees. Some old timers say this tree is an indication of water because it grows in moist soils. I believe the tree they refer to is a subspecies, N. s. biflora, which thrives in the swamps from the mid-Atlantic region westward.

Black Walnut
What is it that stops plants from growing under black walnut trees and is there anything that will grow beneath them?
Juglone, a toxin, is present in roots, leaves, and bark of the tree and is the reason for this problem. The toxin is also produced by English walnuts, pecans and shagbark hickories, but it is not as strong in these trees.
Some plants are immune to this toxin and also don't mind the shade. Among them are creeping bugleweed (Ajuga reptans), Astilbe, sweet woodruff (Galium odoratum), daylilies (Hemerocallis), cinnamon fern (Osmunda cinnamomea), stonecrop (Sedum spectabile) and hostas. Lily of the Valley is another plant that thrives beneath these giants and in my yard, Narcissus and wild violets also do okay. Under another, larger black walnut (Juglans nigra), sage and dusty miller are doing fine.

Can you please tell me if there is something we can put under our black walnut tree that will grow?  We just read about the poison the tree releases into the soil so now we know why nothing grows.
For ground cover, try creeping bugleweed (Ajuga reptans) and/or sweet woodruff (Galium odoratum). My standby, Hostas, do great and there are many varieties available. Astilbe species, daylilies (Hemerocallis), showy stonecrop (Sedum spectabile), and cinnamon fern (Osmunda cinnamomea) will all survive under black walnut (Juglans nigra). 
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Butternut Tree
We bought an old farm that has a lot of black walnuts but one tree is a bit different. The nuts from this one tree look like pecan nuts and when we try to remove the green material around the nut, it leaves brown stains. Can you tell me what this might be?
You must have a butternut tree (Juglans cinerea). Often called white walnut, the butternut thrives in the same range as the black walnut. This tree has been declining in popularity, perhaps because it struggles with some disease problems. Most butternuts that are available from nurseries are grafts onto a sturdier walnut rootstock.
The butternut tree can get very tall, almost 100 feet. The leaves and bark are used to dye woolens dark brown while the roots yield a lovely tan. The husk of the nuts is also used as a stain and, like the chemical from it’s cousin the black walnut, this stain is hard to remove from your skin. Oh, if you soak the nuts in water overnight, they will crack much easier…and the nuts are delicious.
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Cedar Apple Rust
We were told to forget planting crabapples in our yard because of the cedar trees in the neighborhood. What is the connection?
Cedar apple rust, a fungal disease, is the problem. However, you don't have to give up on planting those crabapples because there are many resistant varieties available. In fact, there are too many for me to mention here, but they can all be found in our Sustainable Plants list. You can also ask your nurseryman about them.

Do you recall seeing what are often described as oozy, orange, slimy things with horns, on the Eastern red cedar (Juniperus virginiana) trees after a warm spring rain? These are cedar apple galls produced by cedar apple rust. This is a fungus and it spreads to within a mile of the infected cedar tree, creating rust spots on leaves and this can lead to leaf drop. If you check any cedar trees around your yard, look for brown, shriveled up, nut-like galls called telia, these will become the orange ball-like fungus. When the temperature is right and moisture is available, the telia absorb water and swell. Then long "horns" appear that dry to a dark color. These contain thousands of spores that germinate and are discharged into the air. Within a couple of months, the rust appears on the leaves or fruits of the apple trees, creating a fungal structure that produces spores that are released during dry weather in late summer and go back to the cedars.

You may want to visit our Crab Apple Plantation at East Farm in May (check this Website for specific dates) and see for yourself how beautiful they are and what you would be missing if you didn't plant any.
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Cherry Tree Leaf Spot
Our cherry tree has a problem.  There are holes in the leaves and some of the leaves are folding back from the center and have turned purple. Now the tree is dropping leaves. What is going on?
The tree has cherry leaf spot, a fungal disease. The fungal spores remain on fallen leaves over the winter and when spring rains arrive the spores will be splashed or blown onto new leaves. The fungus thrives in mild wet weather, like a rainy spring. When this fungus is present you will see purple spots on the tops of leaves and clumps of cream-colored spores beneath. The centers of these spots will darken and fall out, leaving holes. In bad cases, the tree looses too many leaves and is weakened as the fungus reduces the amount of nutrients the tree can take in. Also, infected trees often suffer from cold injury during the winter months.
Clean up all litter from beneath the tree in the fall and next spring, right after the tree has bloomed, an antifungal spray can be applied, following directions on the label.
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Chestnut Weevil
This is the first year we have gotten chestnuts from a tree we planted. However, there are white grubs in them and some are black inside. What is the problem?
You have been introduced to a chestnut weevil [there is a lesser chestnut weevil (Curculio sayi) and a larger chestnut weevil (C. caryatrypes)]. One is bad enough but chestnuts have two. The white “worms” you see are larvae. Adults usually lay their eggs in the downy inner lining of the brown shell covering the nut. The larvae feed in the ripening nuts until the nuts drop to the ground and then they exit the nuts and burrow into the ground to pupate. Often you can find a weevil or two around the tree even as late as early October. Pick up nuts daily and destroy those that are infested with larvae in order to reduce the population of grubs that get into the ground. The black insides of nuts are from fungi feeding on damp nuts; this is referred to as chestnut black decay.
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Coppicing
What does coppicing trees mean?
If a tree is known for growing tall and crooked it is often coppiced, that is, the main stem is cut back to the ground to encourage new stems to form from the root. These new stems grow straight up all around the severed stock. Have you ever notice how trees spring up around a stump that is left after a large tree is cut down? This method is used to produce timber as well as for keeping trees small. In the lumber industry, the new trees are allowed to grow until they are large enough to be cut and utilized, usually for specific items like poles, tool handles, and such.
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Cryptomeria
We saw a Japanese cryptomeria tree that has the most unusual cones so we would like to have one. Will this tree  grow in southern Rhode Island?
Cryptomeria japonica, commonly known as Japanese cedar, is hardy to Zone 5 and southern Rhode Island is Zone 6 so I don’t see why not. This evergreen conifer will grow to 50 – 60 feet tall and half as wide, so make sure you have plenty of room, unless you want the compact, shrub form, ‘Elegans Nana’. It prefers rich deep, well drained soil but will thrive in a range of soil types. It has a pyramidal or conical shape with bluish green needles. It is dense when young, developing more clustered, tiered branching with age which makes it look almost fluffy. The foliage develops a distinct bronze to brown color during cold months, especially in windy exposed locations, and then regreens in spring.
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Dogwood
What is the difference between regular dogwood and the Cornus kousa?
Regular dogwood is Cornus florida, a native to the eastern part of this country. Flowers appear before the leaves in spring, appearing in masses of either white or pink among the branches. Cornus florida can grow to 25 feet or more in height and has fruit and wonderful fall color. The problem is that it is susceptible to anthracnose disease. However, Cornus kousa is very resistant to both anthracnose and the dogwood borer. It is from Korea and Japan and blooms later than C. florida, creating cascading branches covered with a thick icing of flowers. The kousa dogwood is also smaller, topping off at around 20 feet, and it has beautiful, flaking bark along with red fruits. It too has outstanding fall foliage. Now, more disease-resistant varieties of both species are available and will give you a choice of color.

During recent rains the dogwood in our lawn fell down and while cleaning it up we noticed lots of tunnels under the bark. Is this what made it weak?
That may have contributed to the problem. Dogwoods are not meant to be planted in lawns, they like to be under larger trees because they prefer the light shading and even moisture that a forest can supply. In the lawn your dogwood was exposed to overheating in the sun, possible injuries from mowers, and other unseen injuries. Any of these problems creates a weakened tree that becomes a target for borers. Even lack of water can create havoc with trees planted out of their normal habitat and during a dry summer there is also lots of water stress. Once the borers are in they can impede nutrient flow, causing the tree to weaken or die. These beetles can open up the door for fungus diseases which then double the problems. Native dogwoods growing in their natural habitat are rarely subjected to these problems.
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Eastern Cottonwood
Part of our large lawn is damp all the time and there are trees growing there that look like aspens I’ve seen Colorado and the leaves remind me of a birch leaf. Can you tell me what it is, please?
You are looking at Eastern cottonwood (Populus deltoides), a relative of the Colorado Aspen. It grows very fast and tall – as much as five or more feet each year and will reach a height of around 90 feet or more. It thrives in damp soil. The foliage of these trees turns yellow in the fall and if there is a stand of them, it brightens up any area on a dreary day.
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Espalier
I've seen fruit trees grown against the walls of homes in the southwest, can we do that here?
Yes, it's called Espalier. The fruit trees are trained to grow flat against a wall or fence by selective pruning. If using a wall, have wires installed about 18 inches apart and running horizontally from 6 to 10 feet across. Height of the espalier is determined by the height of the wall. Also, for the health of the tree, keep the wires at least 6 inches away from the wall.

Plant the tree in the middle and cut off the central stem just below the height of the first wire at 18 inches. This will force new shoots to appear below the cut. As the season progresses, allow only three new shoots to develop. The ones on each side are tied to the wires while the middle shoot becomes the new center trunk. Repeat this procedure until all the wires have branches trained to them and when you have accomplished your goal prune constantly so no new growth is formed. This can also be done with wires stretched between poles and it is often easier to maintain the fruit trees using this method.
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Evergreens
When should we prune our evergreens? We have white pines, spruces, and junipers.
You are talking about narrow leaf, needled evergreens that grow quite rapidly. Dead, broken, and diseased wood can be cut out at anytime of the year but the pruning should wait until early spring. To prune the pines, cut just above the needle whorls. When pruning the spruces, you can cut the younger portion of the branches to keep them in shape but be careful, as older wood doesn't produce new growth very well. Junipers can take a heavier pruning. Yews are often pruned into hedges and hemlocks look best if left alone but may be trimmed lightly to remove branches that are overgrown.

We want to purchase a Christmas tree that can be planted afterwards but the ground is frozen after the holiday, so how do we store the tree?
There are a number of things to consider when using a tree with a root ball wrapped in burlap. First, where is it going to be planted - and figure out the full size of the tree when choosing a site. You must dig the hole and amend the soil in the fall. Then fill the hole with straw or leaves and remove the soil to a warm location. [A hint: A wheelbarrow that can be left in the garage is ideal for this.] Second, chose a tree that has a solid root ball and remember, the larger the tree, the heavier it is and the harder it is to maneuver. A smaller the tree has a better chance to survive.

Store the tree outside in a cool place and keep the root ball moist but do not let it freeze. The ball can be insulated if necessary. To bring it inside, wrap the root ball in plastic and/or place it in a waterproof container. Check it daily and keep it moist. Don't place the tree near heat or a sunny window and plan on keeping it in the house for less than a week. Be careful with decorations as they can damage the branches and don't use any spray snow or flocking. Then, to remove the tree, place it in a cool location for a week before putting it outside. Again, keep the root ball safe from freezing. The last step is to remove the filler from the hole and plant the tree using the original soil. The burlap should be removed. Water well and mulch.
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What kind of pines or evergreen trees can be grown in our area?
In southern New England the most common evergreen is white pine (Pinus strobus), but five other true pine species are on the sustainable plants list, including jack pine (P. banksiana), lacebark pine (P. bungeana), Swiss stone pine (P. cembra), Korean pine (P. koraiensis), and Japanese white pine (P. parviflora).

Other evergreens to consider are: Eastern, or Canadian, hemlock (Tsuga canadensis) which grows well but has a problem with infestation by the hemlock wooley adelgid; the western hemlock; yews (Taxis), which are mostly grown as hedges but can become beautiful trees; Scotch pine (P. sylvestris) and pitch pine (P. rigida); and Eastern larch, or tamarack, which loses its needles every fall, leaving behind branches dotted with cones.

Picea, the spruces are also very adaptable. Species to choose from include black spruce (P. mariana), blue spruce (P. pungens), red spruce (P. rubens), and white spruce (P. glauca), which are all grown here mostly as ornamentals. The Norway spruce (P. abies) is an old standby and balsam fir (Abies balsamea) is a popular Christmas tree.
Of course the red cedar tree (Juniperus virginiana) can be found everywhere, often where it isn't welcome. The true cedar, or northern white cedar, (Thuja accidentalis) is better known as the Eastern arborvitae.

American holly (Ilex opaca) is a beautiful evergreen tree whose branches are desirable for decorating during the winter holiday season.
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Frill Girdling
We just received some written suggestions for modifying a wooded section of our property and frill girdling was recommended as a method to rid the area of some unwanted saplings. We understand what girdling is, but the term frill girdling has us puzzled. Can you help?
This is a method of destroying unwanted saplings or even small trees. With a hatchet or an ax, go all around the trunk a few inches from the ground, making overlapping cuts in a downstroke. (Picture making ruffles or flower petals all around.) This creates pockets into which chemical herbicides are poured that eventually work their way to the root system. It’s just as easy, and a lot better for the environment, to cut the tree down and peel the bark on the stump back to ground level. It won’t be long before fungi attack the stump and it falls apart.
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Garotting
You have answered questions about odd things before and I thank you.  Can you help me with one more?  What is garroting?
I think you must be reading some old manuals or English gardening books.  Garotting is the term for placing something tight, in tourniquet fashion, around a fruit tree trunk, or maybe just one branch, to restrict the flow of sap and thus encourage more fruiting. The mechanism is to make the tree react to a threatening situation and whenever this happens the first response is to reproduce. With a fruit tree, it has to develop more fruit that contain the seeds, which are the reproductive structures.
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Grass-Tolerant Trees
We have a very large lawn and have tried to plant trees but it seems like the grass kills them. Is there any particular tree that would be hardier than others?
Most trees have problems with grass competition if an area around them isn't kept clear. However, there are some that can stand up better than others. Here is a list: dogwood (Cornus), flowering cherry, peaches, and plums (Prunus), Star magnolia (Magnolia stellata), Japanese maple (Acer palmatum), golden rain tree (Koelreuteria), and smoke tree (Cotinus).
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Hamamelis
What is Hamamelis?
Witch hazel, a fragrant flowering shrub or small tree of East Asia and North America. It flowers on bare wood in the cold of late winter. In the fall, the leaves turn yellow with orange and red tones and a small two-seeded fruit appears. Witch hazels prefer an open, sunny spot with damp, but not soggy, acidic soil. They can be raised from seed but takes a full year to germinate; most forms are propagated by grafting or cuttings. All forms of Hamamelis are hardy in our Zone 6 except H. virginiana.

H. x intermedia includes a group of cultivars that have flowers ranging from yellow to a dark coppery tones: 'Arnold Promise' has golden yellow flowers, 'Diane' blossoms in spidery reds, 'Jelena' is bright orange, and 'Ruby Glow' blooms in a dark copper color. This species grows to a height of around 15 feet while H. vernalis, called Ozark witch hazel, only grow to height of six feet. H. vernalis flowers in spring and spreads by means of suckering. The flower is yellowish with a dark red spot in the center. H. virginiana, common witch hazel, can be trained into a tall tree, growing to 20 feet or more, and its blooms appear in autumn as the wonderful butter yellow foliage falls.
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Hardwood Cuttings
How can I make hardwood cuttings to increase a supply of trees?
In October or early November, take cuttings from the current years growth, such as the ends of branches or new shoots from the base of the tree. Cut these pieces into sections 6–10 inches long. If the cuttings are pithy or spongy, make a bottom cut just below a node and a top cut right above a bud. Tie them into small bundles with string, making sure the bottoms are even with each other. Label them and place them standing in a one-foot deep trench, either in the garden or in a cold frame,  and cover them completely with builders sand. The tops should be about an inch below the surface. Leave them untouched all winter. In spring, prepare a special bed in a sunny location by adding sand, peat moss, and vermiculite to the soil so that it is airy and spongy. Plant the cuttings about a foot apart up to the top bud. Water well to settle them in and keep them moist. You don’t want to disturb them until new growth is well established – which could take a couple of years.
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Hawthorn Rust
Our hawthorn tree is beginning to develop yellow spots on the leaves with dark centers in each spot. We sprayed for insects but the spots are still there. 
Are you familiar with cedar apple rust?  Have you seen orange balls on cedar trees in the spring? These masses produce spores that are carried by wind to apple trees, causing spots on the leaves and fruits. Well, the same thing is happening with your hawthorn tree. It’s hawthorn rust and it is caused by a fungus. When it is wet the spores germinate and attack leaves. This is what you are seeing now. Other than making the leaves, and sometimes fruits, look bad, this fungus does little damage.
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Indian Bean Tree
What is an Indian bean tree?
It is a catalpa (Catalpa bignonioides), also known as common southern catalpa and cigar tree. It is hardy for Zones 5 to 10. It is a fast-growing tree and grows up to 40 feet in height and almost as wide. Common catalpa is widely adapted to any soil and climate but is a very messy tree. There is another species, the northern or western catalpa (Catalpa speciosa), that is a little larger and hardier but has fewer flowers.

In the summer, the catalpa tree is covered with trumpet-like flowers that are white but also have hints or spots of brown, purple, and yellow on them. The leaves of catalpa are very large and somewhat heart shaped. The long seed pods are what give the tree its common names. Native Americans smoked the pods. The pods will last into winter and they make quite a mess on the ground. Between the pods, blossoms, twigs, and leaves the area beneath these giants constantly needs attention.
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Judas Tree
I thought that the Judas Tree couldn’t be grown in New England. My neighbor has one that looks a bit different but she calls it Judas tree.  I am a little confused.  Is there more than one type of this tree?
Yes, your neighbor probably has Cercis canadensis, the Eastern redbud which is also called Judas tree. This tree grows very tall in the wild but generally stays under 15 feet when planted as an ornamental. It flowers with deep to pale rose flowers before leaves appear. The leaves have sharp pointed ends and may be purplish to bluish depending on the variety. Cercis siliquastrum, or love tree, is also called the Judas tree but will only survive where the winters are mild. The leaves on this tree are bluish-green with round tips. This tree flowers later in spring and the blooms are larger and darker.
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Larch
There's a tree in our town park that some say is dead. The needles all turned yellow last fall and fell off. Some residents want it removed but the town maintenance says it's not dead and that needle drop is normal for this evergreen. Can you advise us about this?
My advice is to ask the town if that evergreen is a larch (Larix). Larches are deciduous conifers - they shed their needles every fall and resprout them in spring.

Most larches prefer a well drained, but moist soil, except the native tamarack larch which will grow in swamps. The needles of these evergreens either grow singularly along a shoot or in clusters on short spurs on older branches. What is probably growing in your park is Japanese larch (Larix kaempferi), a graceful tree with branches that for a sort of arch. This tree is outstanding in parks. Larches also have very pretty cones especially in spring when they take on a purplish tint.
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Leaf Galls
What are galls on tree leaves?
Depending on the type of gall, they can be an insect, a fungus, or a bacterium. An insect gall occurs when an insect injects a toxin into the plant tissue while feeding and this irritates and blisters the plant tissue, creating odd shapes on the leaves. The roots and stems will swell and the buds and flowers will look odd. Fungal galls, also called stem galls, create large swellings on stems and leaves; some of these turn brown as they age. Stem galls are generally a problem when it is wet in the spring. Both insect and fungal galls look ugly but seldom damage plants. However, bacterial crown gall enters plants through the roots or trunk where there has been damage and it chokes off the flow of water and other nutrients in the plant, creating stunted growth and weakening the plant considerably.
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Lemon Tree
I have a lemon tree that spends the summer outside. When I brought it into my greenhouse this fall, the larger leaves turned very pale and there are light brown hard spots on them. I’ve dealt with scale and these spots are not scale. I don’t want to lose this plant, can you help?
Those light brown spots are edema. These corklike lesions appear on the outer edge of older leaves when there has been too much water and high humidity. At times, these growths turn darker and fall out of the leaf, leaving a hole.

Your other problem is lack of nutrients, especially nitrogen. If you look carefully at your lemon tree, there are some nice dark new leaves beneath the large pale ones. The plant sacrifices older leaves in order to insure that new growth survives. So, remove those pale leaves and don’t overwater the plant. Also, you may need to lower the humidity somewhat until the soil has dried a bit.
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Leyland Cypress
What is a Leyland tree?
You must mean a Leyland cypress (Cupressocyparis leylandii). It is a fast growing (it has been know to reach 50 feet in less than 15 years), very vigorous, and hardy (to Zone 6) columnar tree with flattened foliage that grows in short, sagging sprays. It can tolerate some adverse conditions but not being waterlogged or being in very dry or alkaline soils. These trees make good wind-break and privacy barriers.

Many hybrids are available that provide interesting texture and color. 'Castlewellan Gold' has golden foliage when young but turns bronze with age. 'Haggerston Grey' has a slightly gray cast and the foliage is arranged in irregular sprays. One of the best yellow foliage Leylands is 'Gold Rider'. For a gray-blue, feathery foliage, choose 'Haylor's Blue', and for silver-cream coloring opt for 'Silver Dust'.
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Locust Tree
I’m new to this country and state and I am a bit confused about the term locust tree. Where I came from there was a very tall tree called a Moraine tree and what is called a locust here is different.
There are different trees called locust. You are familiar with the moraine locust (Gleditsia triacanthos), a variety of honey locust that stands up to anything and is thornless. A very rapid grower, the moraine can grow to 75 feet in no time. The flowers grow close on the stems, and straight seed pods hang down where they remain on the tree very late in the season. It grows here also, especially in alkaline soils.

The locust that confused you is Robina, which grows all over the eastern U.S. and is valuable as a hardy timber tree. Wood from this tree is often used for fence posts. The most common variety is black locust (Robina pseudoacacia). This tree pops up all around because of its suckers. There are also thorns or spines along the stems. The seed pods hold kidney shaped seeds and the flowers often droop, appearing to hang below the leaves.
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Magnolia Scale
My star magnolia has some sort of brown fungus growing along the stems. This has made the twigs all out of shape and the leaves have black sticky spots. I don’t want to loose this tree so what can I do?
Actually it isn’t a fungus it’s scale.  Magnolia scale (Eulecanium cornuparvum) is a very tiny insect that winters over on the tree’s branches. The brown material that you see is the insect’s ‘house’. In August the females lay eggs beneath the ‘house’ and when the young (called crawlers) emerge, they move to the cracks and crevices of the bark to spend the winter.
In early fall when crawlers are active, spray them with horticultural oil to smother them. Then, just before the tree comes alive in spring, spray with dormant oil.  Follow directions on the labels.
When the insect starts feeding in spring by sucking sap and nutrients from the bark. However, the insect can’t digest all the sap, so the excess, called honeydew, falls onto leaves. This honeydew can become encrusted with a black sticky mold, thus creating black spots.
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Moving a Tree
We just had to move a 6-foot tree and had to cut off many of the roots. Will it be okay next spring?
To be truthful, you probably have lost the tree. The root system of a tree can be quite extensive. There is a primary taproot, but as the tree grows other roots, called lateral roots, grow out horizontally and these become the dominant root structures: they help anchor the tree but, more importantly, they provide storage for carbohydrates. Also, feeder roots that have tiny root hairs on the ends develop from the lateral roots. These roots transport water and nutrients that have been absorbed by the root hairs back through the tree to the leaves. When you removed these roots, you took away the tree's ability to feed. Sometimes in a construction area you will see a tree that is dead on one side only. If you looked at the base you would see where a machine has cut away the roots on that side. This weakens the entire tree and makes it vulnerable to disease. A healthy tree will have a root system as wide as the crown.
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Oak Leaf Blister
What is wrong with the oak leaves this year? They’re covered in what looks like blisters.
It’s called Oak leaf blister. This is a caused by the fungus Taphrina caerulescens that make the leaves look horrible but rarely does any damage otherwise. This fungus winters over in the bud scales and during cool wet spring weather it enters emerging leaves and forms blisters as it gets into the tissue. The leaves will eventually die and turn brown but may stay on the tree. The fungus produces spores in the fall which will overwinter and if the next spring is cool and wet, it starts all over again.
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Paperbark Maple
What is the maple tree that has peeling bark?
Most likely you mean the paperbark maple (Acer griseum). This is a lovely maple that is ideal for smaller spaces because it grows slowly, though it will eventually reach 20 feet or so. It has dark green leaves that turn a vivid red in the fall, but it is the cinnamon bark that catches your eye. The bark exfoliates (that is, it peels) by curling. Grow this tree in full sun and keep the area beneath mulched. Also, it doesn't like competition from grass. There is another maple species that has curling bark but grows much faster: Acer triflorum. Both of these trees are very hardy in our Zone 6.
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Pawpaw Tree
Can we grow the banana fruit tree here in Rhode Island ? I don’t mean a banana tree but the type that has a soft fruit that tastes like a banana.
You must mean a pawpaw tree (Asimina triloba). It is hardy to Zone 5 so I should think you could. Pawpaws are a favorite tree for wildlife because they establish thickets offering food and shelter. Pruned and trained, a pawpaw tree can grow to a considerable height. The tree favors moist areas in the woods but will adapt to our backyards beneath taller trees in a semi-shaded location and it will grow in the sun. This tree needs deep, fertile, lightly acidic soil, preferably along a stream or swampy area for best naturalizing. It is very difficult to transplant, so secure a balled specimen for planting. There are some great cultivars and one dwarf variety of pawpaw available. If you have raccoons around, don’t plan on any fruit.
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Pine Trees
We have a large pine tree that had yellowing needles late last fall and this spring they are really dropping. We had a driveway installed last summer, is the tar poisoning the tree?
You might say it is killing the tree. If this tree is close to that driveway, the roots have been paved over so the water and air supply to the roots is blocked. When this happens, the tree start to decline, the leaves turn yellow, then brown, and branches start to die. Within several years the tree is dead. The greater the root area, the more severe the decline. To avoid this problem, many landscapers will install pipes in gravel beneath the paving that will allow water and air to penetrate.

My pine trees have globs of icky pitch oozing out from the bottoms. It looks like somebody squeezed a tube of gel from inside the tree. The tops of the trees are turning a rusty color, as well. What is going on?
Are there small holes in the trunk? Is there sawdust oozing with the pitch? If you remove the bark by the ooze can you see grubs in tunnels? If the answers to all of these questions is 'Yes', most likely you have bark beetles, in particular the turpentine beetle. However, if the middle and upper parts of the trunk are attacked but not oozing, then it's the pine bark beetle.

The small turpentine beetles look like grains or rice. Although they feed mostly on pine trees they will also attack spruce and larch trees. The beetle creates the tubes of pitch you described. The adults of both beetles lay their eggs beneath the bark where the larvae hatch and start to tunnel through the bark, but do not emerge until they are adults.

Pitch tubes and yellow/red needles indicate that the tree is in trouble. You probably need to contact an arborist to see if the trees are salvageable. If not, they need to be removed and destroyed.
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Can common pine trees be grown from seed? 
All pine trees can be propagated from seed and most are very easy. Shake the seeds from the cones – bring them inside to warm and open more as it makes releasing these winged seeds easier. When planting ‘wild’ seeds we want to copy the natural habitat: if a seed falls to the ground, don’t cover it with soil. With pines, the seeds fall away from the cones and will be covered with needles and other litter. So, cover the seeds lightly, keep them moist at temperatures of about 65 degrees F, and you should see growth within a month. One of my perennial beds is covered each year by white pine cones and needles so I know that come June seedlings will be springing up all over.
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Pitch Pine
Why are the pitch pines that grow in the woods dying or dead while those in open fields are healthy?
Pitch pine (Piinus rigida) is one of the first trees to reestablish in burned out areas or old fields; chances are the woods were once a field or had been burned over. After years of growth, other trees became established and pushed out the pines. For example, oaks, hickories, locusst, maples and other hardwoods start growing, crowding and blocking out the light, and causing pitch pines to deteriorate and die. First the branches start to dry up then the thick bark falls off, revealing tunnels where insects have been. Many of these trees remain standing 'naked' long after dying, creating homes for wildlife. As they crumble and disintegrate, these pines add much needed humus to the forest floor. Pitch pines growing in the fields don't have all this competition and, therefore, stay much healthier. But if the fields are not maintained other trees will eventually grow at the expense of these pines.
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Redbud
What can you tell me about the redbud tree?  Our landscaper recommended it for the corner of our front yard.
Redbud (Cercis canadensis) is native to the eastern half of the country. It grows in any type of soil, in shade or sun, but it is susceptible to borers and needs to have a reasonable amount of water. Redbud will grow perhaps 8 inches a year and gradually get to a height and width of 25 feet. It really looks good against taller trees such as oaks and has a wonderful display of branches plus bark color during winter months. The trunk and bark will have to be protected from any damage to avoid cankers and attacks by borers. Flowers are pinkish and grow right on the bark of branches, emerging prior to the heart shaped leaves. Some cultivars are available in white and there is also a variety with purple leaves.
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There’s a beautiful redbud tree in my late grandmother’s yard and we want to have part of it in our yard. Can we take a branch and stick it in the soil to root?
Eastern redbud (Cercis canadensis) will grow just about anywhere except in waterlogged soil but not by sticking a branch in the ground. However, you can take  softwood cuttings, that is, new growth at the tips of the branches, in June or July. Put these cuttings into moist sand to about thee inches deep, keep the cutting indoors under lights or in a greenhouse, and keep the temperature around 72 degrees F. They should root in about four to six weeks. 
Cercis can also propagated by layering. Pin the end of a branch onto some soil until it roots. If there is no low growth, a pot that is raised to meet the branch will work if anchored to prevent movement. Once the shoots have rooted, plant them outside but keep them protected over the winter months.
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She Oak
What is a she oak?
She oak (Casuarina equisetifolia), also called beefwood or ironwood, is native to Australia. It looks more like a pine tree than an oak tree. Species are planted as shade trees in southern Florida, where it has naturalized, and in other Carribbean areas. The branchlets resemble horsetails as they are clustered closely around the stems. She oak prefers brackish, acidic soils making it common along swampy coastlines. The wood is bright red, hence beefwood, and doesn’t float. It is valuable for many uses, being hard and durable, and it burns quickly. It’s a great tree for holding drifting sands even with shallow roots.
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Sweet Acacia
We brought a sweet acacia tree from our old home in Texas and planted it here, but now it has lost all the leaves and the branches are breaking off. What is wrong with it?
The problem with your Acacia farnesiana is climate and soil. Sweet acacia is a native of southern Texas and Mexico (Zone 10) and it prefers alkaline soil (pH above 8). You have planted it in Zone 6 and in a soil that is very acidic. Unless we treat our Rhode Island soil with lime, the pH is usually around 5 or lower.

Also known as wattle, there are more than one thousand species of Acacia, all requiring a warm climate. If the fragrant yellow flowers are what make this tree attractive to you, try the golden rain (Koelreuteria paniculata) or golden chain (Laburnum xwatereri) trees.
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Sweet Bay
Can we grow a bay tree in Rhode Island? 
If you mean sweet bay (Laurus nobilis), which is used for cooking, the answer is yes and no. It can be grown in a large container, placed outside during summer months, and brought indoors to a cool but sunny room for winter. Sweet bay grows very slowly but responds well to pruning, making it ideal for a container. It has tiny yellow flowers in spring and produces black berries in fall. Not all varieyies of this tree are aromatic and the leaves have to be dried prior to using to obtain flavor.
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Tree Root Removal
My ornamental cherry tree has a root exposed and whenever I mow, it gets damaged. Can the root be removed?
Removing that root will create more problems than hitting it with the lawn mower; the tree would eventually die. Roots are like branches under the ground and the smaller rootlets at the ends are pulling in nutrients to feed the tree. For whatever reason, this root is growing along the surface, try and cover it with some soil, about 3 to 4 inches creating a small mound, and then put down some grass seed.
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Trees for Birds
What kind of trees can we plant to attract birds?
Besides trees that offer lots of cover, such as evergreens, there are many trees that offer food. Some that you may want to consider are: serviceberry (Amelanchier canadesis), dogwood (Cornus), mountain ash (Sorbus), holly (Ilex), crabapple (Malus), sourwood (Oxydendrum arboretum), plums and cherries (Prunus), hawthorn (Crataegus), Eastern red cedar (Juniperus virginiana) and oak (Quercus). All offer berries or, in the case of oaks, acorns as a source of nourishment, especially during the winter months.

Though classified as shrubs, include the cranberry bush (Viburnum opulus) and elderberry (Sambucus canadensis). Both of these plants grow to a good height - around ten feet or better - and have abundant fruit.

Do a little research on the individual birds you wish to attract and use the results as a guideline. Enjoy your visitors!
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White Pine Pruning
I have a small white pine about 6 feet tall and would like to prune it so it resembles a Christmas tree but I don’t know how.
It will never happen. White pines (Pinus strobes) have long needles and branches that grow in an open airy form while the typical Christmas tree has small needles growing on branches close together. The only pruning white pine usually needs is the removal of dead branches or if there happens to be a problem with the white pine weevil. In certain circumstances, these pines grow too fast, so to keep the foliage dense, one half of the new growth tips are snipped off in the spring. This has to be done very carefully to avoid a making the tree look scrubby.
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Willows
We have a willow on our property that is not the weeping type. Can you tell us if it's a basket willow?
There are so many species of willows that I wouldn't even attempt to name one; all of them are similar - except weeping willows and pussy willows, which are very obvious - and it really takes a botanist to accurately identify most of them. The basket willow (Salix purpurea) is a common shrubby form of willow.

Characteristics that are most common to all willows and are important for identification are: alternate, narrow, pointed leaves; some leaf stalks short or missing entirely; small, paired leaf-like appendages (stipules) at the base of the leaf stalk (on many species); buds covered with scales and silky, gray hairs under the scales; male and female flowers separate and usually on separate plants; and fruits are very small capsules with two sections.
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Witch Hazel
We have a gorgeous witch hazel in our yard that I think needs pruning but my husband says there is no need to do this. What do you suggest?
Witch hazels generally don’t need to be pruned at all. Of course, dead wood or branches that are damaged should be cut out and this is done only in very late winter or early spring...about March. If there are thin branches that don’t appeal to you, go ahead and cut them out at that time also, but remember, witch hazels sort of grow haphazardly.
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More Commonly Asked Questions:

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