Plants Attacked: Juniper, arborvitae, other cedars, pine, hemlock, spruce, Chinese elm, honeylocust, primarily. Also on crabapple, maple, sycamore, box elder, willow, linden, poplar, and many others.

Plants Attacked: Juniper, arborvitae, other cedars, pine, hemlock, spruce, Chinese elm, honeylocust, primarily. Also on crabapple, maple, sycamore, box elder, willow, linden, poplar, and many others.

Scale insects are a peculiar group and look quite different from the typical insects we encounter day to day. Small, immobile, with no visible legs or antennae, they resemble individual fish scales pressed tightly against the plant on which they are feeding. There are over l50 different kinds of scales in Virginia. Many are common and serious pests of trees, shrubs, and indoor plants.

Native to North America, the fall webworm occurs throughout the United States and southern Canada. Its hosts include more than 100 species of deciduous forest, shade, and fruit trees, with preferences varying from region to region.

Native to North America, the fall webworm occurs throughout the United States and southern Canada. Its hosts include more than 100 species of deciduous forest, shade, and fruit trees, with preferences varying from region to region.

Fusarium wilt is a common and lethal disease of mimosa (Albizia julibrissin)1, also commonly known as silktree. In the United States this disease occurs in the east from New York southward and also in Louisiana, Arkansas and California. Fusarium wilt is caused by the fungus Fusarium oxysporum forma specialis perniciosum. Albizia spp. are the only known host of F. oxysporum'' f.sp. ''perniciosum''. Fusarium oxysporum f. sp. perniciosum colonizes and clogs the tree’s vascular (water-conducting) tissue, and interferes with the movement of plant sap. This results in relatively rapid tree death.

"Spongy moth (Lymantria dispar; formerly called gypsy moth), is an invasive pest of hardwood trees in forests and yards. The caterpillars prefer the foliage of oak and other shade trees, but also attack conifers. Spongy moth caterpillars can defoliate large trees during outbreaks, and most homeowners object to the numerous hairy caterpillars and their abundant droppings raining out of infested trees. Since its introduction to Massachusetts in 1869, spongy moth has spread throughout the northeastern US, down in the mid-Atlantic, around the Great Lakes, and into Canada. Most of Virginia is generally infested with spongy moth, but it may not cause widespread defoliation every year."

The primary and sole attribute of beautyberry, a large loosely branched shrub, is the showy display of magenta fruits in the fall.

This vase-shaped medium tree has smooth bark and showy white flowers in the spring. It is also quite drought and alkaline soil tolerant.

There are hundreds of evergreen azalea cultivars which vary in hardiness, size, form, flower color, time of flowering, and foliage. The primary attractive feature of azaleas is the very attractive and showy flower display in spring.

There are hundreds of evergreen azalea cultivars which vary in hardiness, size, form, flower color, time of flowering, and foliage. The primary attractive feature of azaleas is the very attractive and showy flower display in spring.

The species (Prunus laurocerasus) is generally not sold in the U.S. Cultivars of cherrylaurel are low-growing with handsome glossy foliage and white flowers in spring. This species tolerates shade and is used as a border, hedge, and in mass.

Leaves are small and glossy green. Showy small, white/pink, spring flowers are followed by red or black fruit which cover branches in the fall. The fruit display can be quite showy.

Glossy, dark green foliage turns yellow, orange, and red in fall. Flowers may be white, pink, red, or purple. Exfoliating bark is ornamental.

Doublefile viburnum is a large wide spreading shrub with a horizontal branching habit and a spectacular flower display in spring.

Drooping leucothoe is a beautiful and graceful evergreen medium-sized shrub with lustrous, dark green foliage. White bell-shaped flowers bloom in the spring. Its arching branches give it a fountain-like effect. This plant is not suitable for sunny or dry locations.

European white birch is a small/medium fast-growing tree with showy white bark and pendulous branch tips (especially when bearing seed). Small, glossy-green summer foliage turns yellow in fall exposing ornamental white bark. This species is considered to be short lived due its susceptibility to pests.

Flowering quince is a large fast-growing shrub whose main merit is showy flowers (red, orange, white, pink depending on cultivar) in early spring. Uses of this species include hedge, shrub border, or mass plantings. Plants have thorns and therefore need careful placement.

Red tip is a large evergreen shrub. Newly emerging foliage is red and quite showy for a few weeks after which it changes to glossy, dark green. Clusters of white flowers occur in late spring.

Ginkgo is a large shade tree that is tolerant of adverse growing conditions and has a bright yellow fall foliage color. One should only plant male trees since female trees bear fruit that smell like vomit.

Goldenraintree is a medium tree with showy yellow flowers in early summer. Flowers are followed by bladder-like fruits that start out light green, turn yellow, and then brown. Fall color can be fair to good depending on the individual tree. This species is quite tolerant of adverse conditions.

This large fast-growing tree is very tolerant of adverse conditions. Its fall foliage color is a yellow.

Japanese maple is a small tree (usually less than 25 feet tall) with a fine texture and year round appeal. The combination of its showy spring, summer and fall foliage, smooth bark, and interesting form make is suitable for specimen tree status.

This medium to large shrub has purple foliage throughout the growing season. Japanese barberry has thorns which may be an advantage (deer proof, pedestrian traffic control) or a liability (injury to pedestrians).

Beeches, both the American and European species, are large stately and noble trees. They have a smooth sensuous dark gray bark that is exceptionally attractive. Unfortunately, this feature often beckons graffiti practitioners to denigrate trees by carving their initials on trunks.

There are numerous cultivars of Japanese holly. Many are compact, mounded forms with small, spineless, dark-green leaves and black fruit. They are primarily used in mass for borders, backgrounds, and foundation plants.

Japanese pagodatree is a medium/large shade tree with showy flowers in summer. Green seed pods, somewhat ornamental, hang on tree until late in the fall. Flower petals can be messy if tree is used near a house, road, or pathway.

This large shrub has dark green leaves that are large, slender, and wrinkled. This species has showy white flowers in late spring. Clusters of red to black berries form (inconsistently) in late summer.

This medium tree has wonderfully fragrant flowers in June and is tolerant of adverse conditions.

A massive and majestic shade tree with evergreen foliage that is bright olive-green when new and changes to a glossy, dark green when mature.

London planetree is a medium/large species that is very tolerant of adverse conditions. It has ornamental which bark flakes off, exposing tan, greenish and creamy white colors.

Heavenly bamboo is a medium-large upright shrub. In late spring it bears showy white flowers and in the late fall/winter it has attractive reddish foliage (sun) and large clusters of red berries. This species can tolerate full sun or full shade and is drought tolerant. There are several dwarf cultivars that are suitable for small spaces.

The Virginia Department of Conservation and Resources and the Virginia Native Plant Society have ranked Norway maple as a “moderately invasive species” in the mountain, piedmont, and coastal areas of Virginia.

Old fashioned weigela is a large shrub with a coarse texture and showy spring flowers. This plant is best suited for a shrub border. There are several new cultivars which are improved versions (dwarf, foliage and flower characteristics) compared to the species.

Oregon grape holly is a slow-growing, medium to large evergreen shrub with lustrous foliage and bright yellow flowers in spring which are followed by robin egg blue fruit in summer.

In about the first thirty years, the branching habit of the native pin oak is truly unique. The upper branches are ascending, the middle ones horizontal, and the lower ones drooping.

Small, green, summer foliage. When unpruned, pyramidal clusters of small white flowers produce black berries.

Red maple is a fast-growing medium/large shade tree species with a spectacular fall foliage color. It has showy red flowers in the spring. There are many cultivars of this species that vary in form, tolerance of wet conditions, and fall color.

Rose-of- Sharon is a large shrub with showy, relatively large single or double flowers, that bloom in summer. Flower colors include white, red, purple, violet, and blue.

Pyracantha is a large, fast-growing shrub has showy white blooms in spring and a spectacular display of orange/red fruit in the fall. This plant requires pruning since unpruned plants are very rangy looking.

Smokebush is a small tree or large shrub depending on how one prunes the plant. Leaves of the species are green. Depending on cultivar; leaves can be purple or yellow during the growing season.

This is a magnificent large evergreen tree with very large, wonderfully fragrant white flowers in late spring and early summer. There are many cultivars with variations in tree shape and size, flower, and foliage characteristics.

Southern waxmyrtle is a large evergreen shrub or small tree depending on how one prunes it. This species tolerates wet and dry soils and females have a somewhat showy display of gray berries in the fall/winter.

Sugar maple is a medium/large shade tree with a no less than spectacular fall foliage display. There are many cultivars; cultivar characteristics include growth rate, form, and fall foliage color.

Pyramidal in youth, round to oval at maturity Sweetgum is a medium/large tree with very showy fall foliage colors. It tolerates moist to dry soils. A notable disadvantage is the mess created by the fallen spiny fruit (gum balls).

Thornless honeylocust is a large tree that tolerates both wet and dry soils. One should select a cultivar for fruitlessness and pest resistance.

Tuliptree is a very tall, large tree with a straight trunk. It bears beautiful tulip-shaped flowers in May but generally go unnoticed since they high in the tree.

Vase-shaped with arching branches Vanhoutte spirea is a large shrub with graceful arching branches. Its main claim to fame is it abundant and showy display of white flowers in spring. This species is best used in a shrub border or in mass.

White oak is a magnificent large spreading tree. This species is somewhat slow growing but is well worth the wait. Do not plant this tree in an area that is apt to be subjected to soil compaction.

Winterberry is a large shrub and somewhat informal in character. There are cultivars that are shorter and have a more formal appearance. This native wetland species has very showy bright red fruit (on female plants) in early autumn that persist till February.

Wintercreeper euonymus is a low-growing evergreen ground cover that will climb when it encounters a vertical surface. There are several cultivars which vary in foliage color and height.

This and several other similar cultivars are used in landscapes as border plants or in mass. This species is very tolerant of most adverse landscape conditions. Some female cultivars have stems laden with very showy persistent red fruit. This species is suited to warmer areas of Virginia (zone 7 and higher).

Pales weevil feeds on all pines within its range. It will also feed, although to a lesser extent, on Douglas-fir, fir, hemlock, juniper, larch, northern white-cedar, and spruce.

Pales weevil feeds on all pines within its range. It will also feed, although to a lesser extent, on Douglas-fir, fir, hemlock, juniper, larch, northern white-cedar, and spruce.

The emerald ash borer (EAB) is a serious pest of all species of ash in North America. Only Asian species of ash have shown resistance to this pest. It attacks all ash found in Virginia and is widespread in the state.

Twisted and curled needles are the most apparent damage from feeding by the balsam twig aphid. Feeding can also cause roughened bark on the twigs. Extensive feeding can cause a general decline and reduced vigor of the tree, yet in many cases is cosmetic and not particularly damaging. The major problem is that curled needles reduce the marketability and value of Christmas trees. Balsam twig aphids also produce honeydew, a sticky material that drops to needles and twigs below. At times the honeydew can become a growth medium for sooty mold, which turns the needles and twigs black.

The pine bark adelgid was introduced from Europe and is now widely distributed in North America, occurring principally throughout the native range of eastern white pine. This insect is also found on Scots and Austrian pine.

Bacterial leaf scorch is an important and often lethal disease of many landscape trees, particularly in the southern and eastern U.S. In Virginia landscapes it is most often observed on oak, elm, and sycamore; however, many other landscape tree species are susceptible to this disease. The bacterium that causes bacterial leaf scorch colonizes the tree's water-conducting tissue (xylem), disrupting water movement and reducing water availability to the tree. The symptoms of bacterial leaf scorch are very similar to symptoms of other problems that limit water uptake. This is why marginal leaf scorch symptoms caused by other problems, such as drought stress or root disease, are often mistaken for symptoms of bacterial leaf scorch. Laboratory identification of the causal bacterium (Xylella fastidiosa) from affected petiole and leaf tissue is necessary for positive confirmation of the disease.

Native to central Europe, the balsam woolly adelgid is now distributed throughout eastern and western North America. It attacks all true firs, Abies spp., including balsam and Fraser fir.

The redheaded pine sawfly occurs from S.E. Canada throughout the eastern U.S. Feeding is primarily restricted to the two and three-needled pines, such as Jack, red, shortleaf, loblolly, slash, longleaf, and pitch pines. White pine and Norway spruce may also be defoliated.

Austrian pine is a medium to large pine tree that is quite dense in its youth (about first 20 years). As most other pines, with age this species loses its lower branches and assumes a flat-topped irregular form.

Bigleaf hydrangea is a very popular flowering shrub. Flowers are mostly produced in June and July but newer cultivars (that flower on new growth) flower through the summer. Depending on the particular cultivar, bigleaf hydrangeas bear one of two types of flowers.

Bradford callery pear is a medium size fast-growing tree that has an exceptionally showy flower show (March/April), has handsome glossy leaves that turn a brilliant red-orange in fall, has a symmetrical oval to round shape with a neat branching pattern, is resistant to fire blight, and is remarkably tolerant of drought, heat, pollution, and poor soils.

Canadian hemlock is a large very beautiful and graceful conifer native to moist forests and stream banks of the Appalachian Mountains. Unlike most other conifers, it is shade tolerant but will tolerate full sun.

Carolina sIlverbell is a medium sized tree with a very showy display of bell- shaped white flowers in April. Brown four-winged fruits are persistent into the fall that are considered aesthetically pleasing by some; at the least they are interesting and an aid in plant identification.

True cedars, the genus Cedrus, are large exceptionally beautiful conifers. In youth they are conical trees but mature into grand picturesque specimens. There are three cedar (Cedrus) species in the landscape trade.

Chastetree is a large fast-growing shrub or small tree that produces showy pale violet flowers in June/July through September. This species is quite drought tolerant.

Chinese juniper, the species, is a medium/large tree, however, only cultivars, ranging from small trees/large shrubs to low-growing shrubs are sold at garden centers.

Colorado spruce is usually a dense conical conifer. Within the species there is a botanical variety called the Glauca Group (var. glauca). The foliage of seedlings from plants in the Glauca Group can vary from green to bright powder blue.

Common Periwinkle is an attractive low-growing broad leaved evergreen ground cover. The plant produces 1-inch blue-violet flowers in early spring that are noticeable upon close inspection. Plants do best in light shade but will tolerate full sun and full shade; full sun plantings often show leaf discoloration.

Cornelian cherry dogwood is a multi-stem large shrub or small tree depending on how one prunes it. In either case, its main showy characteristic is in February/March at which time it produces numerous small yellow flowers which collectively are quite showy.

Creeping juniper, a conifer, is a ground cover species represented by numerous cultivars (more than 60) that vary in height, form, foliage color, and the presence of juniper “berries” (on females).

Dawn redwood is a fast-growing large deciduous conifer with a distinctly conical form. This species is quite majestic; its feather-like foliage confers a fine texture. Fall foliage color is variable but a pleasant brown-orange color is typical.

Dwarf Alberta Spruce is quite common in the garden center trade. It is a slow- growing densely compact conical conifer with a formal look due to its dense symmetrical form.

Eastern arborvitae is a conical conifer that has a stately appearance and useful as a specimen plant (used alone as a focal point), as a border planting, or anywhere a conical evergreen is appropriate.

Eastern redcedar is widely distributed throughout the eastern US. It is a pioneer species in that is quickly populates farm fields and other open areas (seeds spread in bird droppings). Its common place presence throughout makes it suffer the stigma of being too familiar.

English ivy is an attractive evergreen ground cover and vine that grows in full sun or full shade. While very attractive due to its lustrous green foliage and numerous foliage variations found in the cultivars, and being very tolerant of adverse conditions, this species has been documented as an invasive species.

Main Features: Generally only dwarf forms of mugo pine are sold at garden centers; the species (non-dwarf) is a multi-stem medium to large tree. Dwarf forms vary in their growth rate from 1 to 8 inches per year, and in their form (mounded to upright oval). Hence, cultivar selection is important to match the cultivar to the available garden/landscape space.

Foliage: Flat scale-like foliage without a sweet fragrance when crushed; branches are held in a flat vertical plane; evergreen Height: About 20 feet Spread: About 15 feet

There are two species of dogwoods that have showy red stems in the winter, Tatarian dogwood (Cornus alba) and redosier dogwood (C. sericea). Both are deciduous medium to large shrubs and have similar flowering and fruit characteristics, as well as cultural aspects. Thus, the general information (Summary, Plant Needs, Functions, and Care) will be presented for both species). Each species has several cultivars that vary in stem color and foliage variegation; cultivar information will be presented for each species in the Additional Information section.

Adults are usually black or brown beetles with an oval to oblong shape. They have clubbed or knobbed antennae and the economically important species typically measure 3–6 mm (0.12–0.24 inch) long. Some sap beetles have short wing covers that do not cover the entire abdomen. Some species have flattened bodies while others are more convex. Many sap beetles are a dull color, sometimes with mottling or spots. One common sap beetle, the picnic beetle [Glischrochilus quadrisignatus (Say)], is an attractive shiny black beetle with four yellow-orange bands or spots on the wing covers.

Heavily infested trees will have large numbers of scales on twigs and branches. Scales may also be found on exposed roots and on the trunk of young trees. Scale insects feed on plant sap with their long thread-like mouthparts (stylets), which are several times longer than the insect itself.

Invasive exotic species are plants that are not native to a given area and have the ability to out-compete indigenous plant species. Invasive exotics are often brought into their non-native surroundings by humans with good intentions.

Autumn olive was introduced to the U.S. from Japan and China in 1830. It was originally planted for wildlife habitat, shelterbelts, and mine reclamation, but has escaped cultivation. It is dispersed most frequently by birds and other wildlife, which eat the berries.

Several species of Asian honeysuckle have been introduced in the United States for their ornamental and wildlife values. Honeysuckle is perhaps the most widespread exotic invasive in the U.S., now found in at least 38 states. The Asian honeysuckle produces abundant seeds which are dispersed by birds and other wildlife. It also spreads by sprouting from its roots. Because it tolerates shade from other plants, it grows in forest understories.

Forest management is a complex process. Silviculture—a system in which healthy communities of trees and other vegetation are established and maintained for the benefit of people—uses forest ecology to guide complex management prescriptions that mimic forest disturbances and processes. Silvics—the natural characteristics of trees—play an important role in prescribing effective silviculture.

Bonsai is an art form that stems from ancient Asian culture, originating in China and developed by the Japanese. In the 13th century, the Japanese collected and potted wild trees that had been dwarfed by nature. These naturally formed miniatures were some of the first bonsai.

There are many tree species that can be successfully grown in Virginia, but are rarely seen in our landscapes. Although not ordinarily recommended or readily available, these trees may be useful to carry out a specific landscape theme, to substitute for an exotic type which is not locally adapted, or may be prized for unusual form, flowers, fruits, bark, or foliage.

Conifers, also known as narrow-leaved or needled evergreens, are planted primarily for the attractiveness of their evergreen foliage. The variety of sizes, shapes, and colors available contributes to their popularity. Conifers range in size from prostrate plants growing only a few inches tall to large trees. Shapes include flat ground covers; horizontal spreaders; upright, pyramidal forms; and even weeping and contorted forms. Foliage color ranges from a gold and cream variegation to all shades of green, gray-green, and blue-green.

Landscapes are composed of plants that form ceilings, walls, and floors spaces. Groundcovers serve as attractive carpets of foliage that cloak and beautify our landscape “floors” (fig. 1). A groundcover is a low-growing plant species — 3 feet tall or shorter — that spreads to form a relatively dense layer of vegetation. In covering bare soil, groundcovers reduce soil erosion and provide habitat for insects and other animals, along with a host of other positive environmental effects.

Trees are the basic element for any landscape plan. They set the stage for the entire home grounds design. The type used and their location determine to a great extent what other plantings are appropriate. Providing shade usually requires tall, sturdy, long-living species. Density of foliage, which determines the amount of shading, is important. A tree such as a Norway maple will produce a very dense shade that prevents other plants from growing under it, while a honey locust will produce a light partial shade which is not a hindrance to other plants growing below it. Deciduous trees should be used to shade the south windows of a home in the summer, thus allowing the sun to penetrate in the winter.

What is a shrub? A shrub is generally considered a multi-stem woody plant that is less than 15 feet tall. Of course, this and other plant size categories are definitions contrived by humans to categorize nature. What is the difference between a large shrub and a small tree? In many cases, there is none. A shrub does not become a tree just because it grows higher than 15 feet. Classifying plants into ground cover, shrub, and tree designations are aids to allow us to conveniently classify and describe plants, albeit with a significant amount of ambiguity.

Maintenance programs should be developed for trees and shrubs in both residential and commercial landscapes. A good maintenance program includes monitoring and controlling insect and disease problems, suppressing weed competition, and making timely applications of water, mulch, and fertilizer. Tree and shrub fertilization is especially important in urban and suburban areas of Virginia where soils have been altered due to construction. These urban soils tend to be heavily compacted, poorly aerated, poorly drained, and low in organic matter. Even where soils have not been affected, fertilization may be needed as part of a maintenance program to increase plant vigor or to improve root or top growth.

Los árboles y arbustos necesitan nutrientes para crecer y estar sanos. Los tres nutrientes más importantes son nitrógeno, fósforo y potasio. Un análisis de suelos es siempre la mejor manera de saber qué nutrientes se necesitan y la cantidad necesaria de cada uno.

Using trees as living screens can easily enhance living and working spaces. Before selecting trees for screening, first determine the screen’s purpose, whether functional or environmental. Screening can be used to define an area, modify or hide a view, create privacy, block wind, dust, salt and snow, control noise, filter light, and direct traffic flow.

To grow, all trees require air, light, water and nutrients. Some trees can survive over a wide range of climatic and soil conditions, whereas others are very site specific. Both wet and dry sites present establishment and growth challenges, making selection of the right tree for the right site very important.

Trees can become a dangerous liability when they are planted near utility lines and their mature size leads to conflicts with the utility lines. Trees can damage utility lines, disrupt power delivery, and create hazardous conditions. Utility companies expend significant resources managing tree conflicts through pruning and removal. Despite the potential for these conflicts, property owners often desire trees near utility lines for amenity and privacy. To prevent recurring conflicts with utility lines, trees with compatible mature size should be planted near utility lines. In this publication are recommendations for minimizing tree conflicts with utility lines along with an extensive list of utility line compatible tree species suitable for landscapes in Virginia and the Mid-Atlantic region.

Concentrated sodium (Na), a component of salt, can damage plant tissue whether it contacts above or below ground parts. High salinity can reduce plant growth and may even cause plant death. Care should be taken to avoid excessive salt accumulation from any source on tree and shrub roots, leaves or stems. Sites with saline (salty) soils, and those that are exposed to coastal salt spray or paving de-icing materials, present challenges to landscapers and homeowners.

Select trees and shrubs well-adapted to conditions of individual planting sites. Poorly-sited plants are doomed from the start, no matter how carefully they’re planted.

Spider mites (Family Tetranychidae, Order Acari) are not insects; they are closely related to spiders, harvestmen (daddy longlegs), and ticks. Unlike insects, which have six legs and three body parts, spider mites have eight legs and a one-part body. They also lack wings, antennae, and compound eyes. Individual spider mites are almost microscopic, yet when they occur in large numbers, they can cause serious damage. Dozens of species attack shade trees, shrubs, and herbaceous plants.

The spruce spider mite (Acari: Tetranychidae, Oligonychus unuguis (Jacobi)) lives in all areas of Virginia and is widely distributed throughout the temperate regions of the United States and Canada. It attacks spruce, arborvitae, juniper, hemlock, pine, Douglas fir, Fraser fir, and larch, among others.

The most effective form of plant disease control in the landscape is prevention. Disease prevention can be as simple as choosing the right plant for the right place at planting time. This fact sheet was developed as a guide to shrubs that generally experience few problems in Virginia landscapes. Using these species for new plantings should help you avoid troublesome disease and insect problems in your landscape.

La forma más eficaz de controlar las enfermedades de los cultivos en nuestro jardín es la prevención. La prevención de enfermedades puede ser tan sencilla como elegir el cultivo adecuado para el lugar adecuado al momento de cultivar. Esta hoja informativa fue desarrollada como una guía de los arbustos que generalmente experimentan pocos problemas en los paisajes de Virginia. El uso de estas especies para las nuevas plantaciones debería ayudarle a evitar problemas de enfermedades e insectos en su jardín.

Many of the tree species commonly planted in Virginia landscapes suffer from disease problems. Although some diseases can be cured, most must be controlled on a preventative basis. The best option for new plantings is to choose species that have a low risk of developing disease. Listed below, in alphabetical order, are some choices of problem-free trees for Virginia landscapes.

Powdery mildew fungi attack a variety of ornamental plants grown in Virginia.

Anthracnose is a generic term for a disease that occurs on many ornamental and forest trees. A number of different fungi cause anthracnose on various hosts. It occurs most commonly and severely on sycamore, white oak, elm, dogwood, and maple. Other host plants that usually show only minor symptoms of anthracnose include linden (basswood), tulip tree, hickory, birch, and walnut. Anthracnose fungi may be host-specific, as in the case of sycamore anthracnose, which infects only sycamore and not other tree species. Anthracnose fungi have similar life cycles, but require slightly different moisture and temperature conditions for infection.

Leaf and flower gall is a disease that is common on azaleas and camellias in the spring. The disease has also been reported on other members of the plant family Ericaceae. It occurs in home landscapes and nurseries, and is often seen on flame azaleas in the forest in the spring. The disease is caused by species of the fungus Exobasidium.

Black root rot is a fungal root disease that is a serious and extremely common problem on Japanese holly (Ilex crenata), a commonly used evergreen landscape shrub. Inkberry holly (Ilex glabra), blue or Meserve holly (Ilex crenata) are also very susceptible to black root. The disease is not as commonly diagnosed on blue holly and inkberry holly as on Japanese holly in the Virginia Tech Plant Disease Clinic. The black root rot pathogen is soil-borne and can be introduced into a landscape on infected nursery plants. Chinese holly (Ilex cornuta) and English holly (Ilex aquifolium), are resistant to the black root rot pathogen.

This publication attempts to distinguish the symptoms of these four major diseases of dogwood.

English boxwood, are susceptible to several diseases that can decrease their effectiveness in established plantings. The major diseases of boxwood are discussed

Wilt and root rot of rhododendron and azalea are symptoms of a disease caused by the soil-inhabiting water mold fungus Phytophthora.

Sooty molds of trees and shrubs commonly occur throughout Virginia on conifers, hardwoods, and other plant species

Verticillium wilt is a serious vascular wilt disease affecting many shade tree species and over 80 tree genera, as well as many woody ornamental landscape plants, and herbaceous and vegetable plants. Verticillium wilt most commonly occurs in nursery, orchard and landscape locations. Maple (Acer spp.) are a tree genus commonly associated with the disease, but Verticillium wilt occurs on many other trees and woody ornamentals used in landscapes. Verticillium wilt more commonly occurs in locations with colder climates than Virginia; however, Verticillium wilt does cause disease on trees and woody ornamentals in Virginia.

Rose rosette disease (RRD) is a serious disease problem of cultivated roses, and over the past two decades RRD has become the most important rose disease in North America. RRD is caused by Rose rosette virus (RRV). RRD leads to stunting, decline and death of roses, yet there are no easy, economical or particularly effective management tactics for RRD. Currently, the major rose cultivars available to growers are susceptible to RRD.

Pesticide use affects the quality of human health, the environment, and nontarget organisms in the ecosystem. Therefore, any pesticide application warrants a careful assessment of the expected benefits and risks. Too often, however, homeowners use pesticides inappropriately or without careful consideration of alternatives. This fact sheet outlines general pest control tactics that can easily be implemented for home lawns and gardens, along with other information that home owners can use to make sound pest management decisions. The intent is to ensure that homeowners are aware of alternative control tactics and pesticide characteristics, and that pesticides are used properly and only when necessary

Landscape trees are valuable assets to your property and for your community. Keeping your trees attractive, healthy, and safe requires careful attention to their planting and care throughout their lives. While many people have a green thumb, there are situations that arise where the expertise of an arborist is needed to address complex or potentially hazardous tree care needs. The purpose of this publication is to inform home owners, property managers, municipal planners, and others about the tree care services provided by an arborist and the steps that should be taken to hire a qualified arborist.

Many forest owners value their forest for wildlife habitat, recreation, and aesthetics. Given accurate information, many want to manage their woodlot using sound silviculture but clear-cutting as a regeneration method may not be visually acceptable. While a profitable timber harvest is of interest, a visually pleasing residual stand may be more important. To meet this objective, Stand D1 of the SVAREC forests was selected to demonstrate All-Age Management using group selection silviculture and individual thinning of select trees to create four age classes.

Most forest owners value their forest for wildlife habitat, recreation and aesthetics. Given accurate information, they may manage their woodlot to achieve these and other goals using sound silviculture. Thinning over-stocked woodlots is one silvicultural management tool. Thinning can modify spacing and diversity of species to meet desired goals which may include timber, wildlife, aesthetics and more. Thinning also improves woodlot vigor by removing over-mature, suppressed, defective or weakened trees. To meet theses objective, Stand D2 was selected for a thinning research & demonstration site.

Research into the attitudes and actions of private forest landowners shows that although very few own their forestland for the purpose of producing timber, most will sell timber at least once in their lifetimes. Private forest landowners sell timber for a variety of reasons that range from purely financial to solely for management purposes. Often landowners do not consider selling timber until they have an immediate need for cash. Other times the landowner has planned an immediate commercial thinning with a full timber harvest scheduled in 10 years. Whatever the reason(s) for a timber sale, careful consideration of objectives is paramount.

Timber harvesting is a valuable tool to help forest landowners realize certain financial and land management goals. Following are some suggestions to consider before selling timber.

Since at least the late 1800s, scientists and forest managers in the United States have recognized that forests have strong influences on water resources (Hewlett 2003). Today the connections between forests and water are widely reported in the news media, promoted by natural resource agencies, and investigated by specialists such as hydrologists, dendrologists, foresters, forest biologists, and water managers. Tree structures and functions influence at least four major areas of water-resources concerns: (1) water quality, (2) aquatic habitat, (3) water quantity, and (4) the interactions among water, climate, and energy use. This publication provides a basic introduction to Virginia's trees and a foundation for assessing the connections between water and trees.

Restoration of shortleaf pine (Pinus echinata Mill.) in Virginia has become a priority of various state and federal agencies. For shortleaf pine restoration to be successful in Virginia, private lands must be considered because 89 percent of forestland in Virginia is privately owned, and most private landowners are likely to use commercially available seedling sources. Shortleaf seedlings from commercially available sources in Virginia, Arkansas, and Missouri were planted in two sites in Southeast Virginia to test growth and yield. After one year, height and ground-line diameter were measured and observations were made on health and mortality of the plants. The Virginia seed source was significantly taller than the Arkansas source. At the first site, mortality and disease were low, but at the second site, mortality and poor health were very high, possibly due to soils combined with weather conditions. No significant seed source effects on disease and mortality were found at either site.

Big trees are natural wonders that inspire people and play important roles in forest ecosystems. The Virginia Big Tree Program documents, curates, and publicizes the largest trees known to exist in Virginia. Trees are scored and ranked using measurements of their physical dimensions.

The locust borer is a native insect that attacks black locust (Robinia pseudoacacia L.) and its ornamental cultivars. Adult locust borers are conspicuous black and yellow beetles with long black antennae and reddish legs. There is a yellow W-shaped band across the wing covers with other yellow stripes.

Psocids are small, oval insects with soft bodies that usually measure only several millimeters long. A psocid measuring 6 mm (0.25 inches) long is rather large for this group of insects. Psocids generally occur in shades of brown, black, or pale colors; some have distinctive mottled or striped markings.

Galls made by made by aphids, adelgids, phylloxerans, psyllids, and midges occur on many different plants. Galls are abnormal growths of plant tissue induced by insects and other organisms. Gall-making parasites release growth-regulating chemicals as they feed, causing adjacent plant tissues to form a gall. The parasite then develops within the relative security of the gall. Most are harmless to trees, but a few are pests.

Although honey bees are well known for pollination and honey production, other bees at times impact humans in various ways. These native bees range from beneficial to annoying, sometimes at the same time. Native bees are important pollinators for fruit and vegetables.

Rice-shaped holes about 1/16 inches result from adult feeding. Larval feeding forms mines, usually two per leaf. If they are both on the same side of midrib, one is extensive, and the other dwarfed. If the insect lays eggs on opposite sides of the midrib, both mines develop normally.

In Virginia and other Mid-Atlantic states, the invasive brown marmorated stink bug (BMSB) has become a serious nuisance pest (Rice et al. 2014). Each fall, these insects aggregate on buildings seeking shelters in which to spend the winter months.

Cankerworms are also known as inchworms, loop worms, and spanworms - this is credited to their distinctive way of moving. In order to travel, a cankerworm must grab leaves or branches with its front legs and then pull the rest of its body forward. This causes the abdomen area to contract and gives the worm the appearance of arching its back.

Description of Damage: The bark becomes roughened and encrusted with scales. Branches and limbs die back and result in a rapid decline in tree vigor, occasionally resulting in the death of trees. Seriously weakened trees are common in Virginia as a result of scale populations, especially red and silver maples.

Goldenchain tree is a small tree that is primarily noted for its very showy pendulous flowers (16 inches plus in May). This species is best grown in zones 5 to 7 and generally requires afternoon shade. Plants in full sun are often stressed and succumb to pest problems. ‘Vossii’ is a long-flowered cultivar.

Hinoki falsecypress is a medium to large conifer. There are numerous cultivars that are more popular and prevalent in the nursery trade than the species. However, the species is a very beautiful conifer and well worth the hunt in garden centers or mail order nurseries. In my opinion, the hinoki falsecypress (species, not a cultivar) is more desirable than the sawara falsecypress (Chamaecyparis pisifera species, not a cultivar) since hinoki falsecypress foliage is denser and brighter green, and the bark is a brighter red-brown color. Cultivars vary in size (growth rate), foliage size and color, and form.

Japanese cryptomeria is a handsome medium to large conifer with a conical to narrow conical form. This species is fast growing and is relatively popular in the trade. If lower limbs are removed, one can observe a beautiful orange-brown bark (on most trees). The foliage tends to turn brownish on the south side of the plant in winter due to desiccation; however, foliage will turn green in spring. Japanese cryptomeria does have a few disease problems, although these are not considered a major issue at this point in time.

Japanese stewartia is a strikingly beautiful small tree. It has very showy white flowers with gold-colored stamens in June; bright maroon-red fall foliage color; and with age develops bark with a patchwork of brown, orange-brown, and cream colors. Bark characteristics vary from tree to tree and some trees have lustrous bark.

Japanese zelkova is a medium to large shade tree with a distinct vase shape. This species is quite drought and heat tolerant; its use as a street tree species is testimony to its toughness. Fall foliage colors range from fair to quite good (orange to bronze-red to maroon) and will vary from tree to tree (seedling-grown trees) or from cultivar to cultivar.

Katsuratree is a magnificent medium to large shade tree. Its accolade-deserving qualities are its form, beautiful foliage, and bark. Seedling-grown trees have a variable form ranging from upright oval to pyramidal to wide spreading. This species has a tendency to develop major branches near ground level, and if one has ample space, such low slung trunks give the lower portion of the tree a majestic “octopus-like” appearance.

Lacebark pine is a medium (sometimes large) conifer species that has strikingly beautiful bark. Bark is a camouflage-like patchwork of greens, silvery-white, creams, browns, and red-browns. There is a great amount of tree to tree variation in bark color; patchwork of colors begins to appear on approximately 2 inch diameter branches.

Leyland cypress is a fast-growing conifer that is one of the most popular landscape conifers in the eastern U.S. In addition to its vigor, this species is relatively drought tolerant and can be pruned into a hedge.

Mimosa is a fast-growing small tree with very attractive pink pin cushion-like flowers in summer. This species has tropical-like foliage (bipinnately compound foliage with very small leaflets) that confers a very fine texture to the tree.

Norway spruce is a medium to large conical conifer. When young (first 10 years or so), the plant is stiffly conical. With age, the secondary branches hang from the primary horizontal branches.

Paperbark maple is a small tree with exceptionally beautiful peeling cinnamon-colored bark. Most branches, those that have a diameter about one-half inch and larger, will have peeling (exfoliating) orange-brown bark.

Red buckeye is typically a multi-trunk small tree (large shrub). Its claim to fame is the red flowers that cover the plant in April/May. Flower stalks (panicles) are about 8 inches long with 2 inch long red tubular flowers. Flowers are pollinated by ruby-throated hummingbirds.

River birch is a fast-growing shade tree species. As the common name implies, river birch trees tolerate wet soils and are a very suitable species for portions of the landscape that characteristically have moist soil, such as low areas or in poorly drained soils.

Saucer magnolia is generally a small (occasionally medium) multi-stem tree that is known for its outstanding flower display in March (February in southern U.S. and April in northern U.S.). Flowers are about 8 inches in diameter; outer sides of petals (actually called tepals; about 9 tepals) are various shades of pink-purple while inner sides of tepals are white.

Sawara falsecypress is a medium to large conifer. There are numerous cultivars that are more popular and prevalent in the nursery trade than the species. Cultivars vary in size (growth rate), foliage type and color, and form. Many of the cultivars are considered “dwarf” since they do not attain the mature size of the species.

Scotch pine is a medium tree. Like most pines, the first 20 or so years of its life it has a conical shape and with maturity it loses its lower limbs and has an irregular flat topped or oval shape. Scotch pine has a relatively showy orange colored bark (with the exception of the lower trunk). It is also relatively drought tolerant, thus it is suitable for landscape sites that tend to be dry.

Sourwood is a small slow-growing tree although forest specimens exceed this small status. This species is certainly worthy to be a specimen plant (sufficient attributes to be featured as a focal point). Sourwood has beautiful lustrous foliage in the growing season which turns a bright maroon to pink-red in the fall.

Star magnolia is a small multi-stem tree that is known for its outstanding flower display in March (February in southern U.S. and April in northern U.S.). Flowers are about 3 to 4 inches in diameter and fragrant; outer sides of petals (actually called tepals; about 12 to 18 tepals) are white or blushed with pink while inner sides of tepals are white.

Umbrella-pine is a beautiful slow-growing conical conifer. Its beauty is mostly derived from the unusual texture that is imparted by the glossy dark-green needles that occur in whorls along the stem.

Washington hawthorn is a small tree (single or multiple trunks) with showy white flowers in June. Trees produce an abundance of persistent glossy bright red fruit (about 0.25 inches in diameter) that result in a spectacular fruit display that persist into winter months.

American hornbeam, also called blue beech, musclewood, water beech, and ironwood, is a small to medium tree. In its youth, and even sometimes at maturity, this species tends be multi-trunked and densely branched. It also tends to develop major branches near ground level which can be a desirable or undesirable characteristic depending on how this species is intended to be used in the landscape.

Beeches, both the American and European species, are large stately and noble trees. They have a smooth sensuous dark gray bark that is exceptionally attractive. Unfortunately, this feature often beckons graffiti practitioners to denigrate trees by carving their initials on trunks.

Chinese elm is a medium to large fast-growing shade tree. This species is quite tolerant of drought and poor soil; hence, it has been extensively used in urban situations. There are numerous cultivars; cultivar selection criteria include cold hardiness, form, growth rate, foliage characteristics, and bark showiness.

Chinese pistache is a medium-size shade tree. It is quite tolerant of full sun, hot, and dry conditions (once established). This species has separate male and female plants (dioecious); female plants (if male trees are present) will produce clusters of reddish pea-size fruit that are somewhat attractive.

Douglasfir is a large and stately narrow conical conifer that is native to the Pacific Northwest (P. menziesii var. menziesii) and Rocky Mountains (P. menziesii var. glauca). Trees in native habitats are often taller than 100 feet; however, landscape trees rarely exceed 50 feet.

Boxwood blight is a devastating disease of boxwood that results in defoliation and decline of susceptible boxwood. This best management practices factsheet provides guidelines for home growers of landscape boxwood to avoid introduction of the boxwood blight pathogen into a landscape or, if the disease is already present in a landscape, to manage to disease in the most effective manner and avoid spread of the disease to new locations.

To provide leadership in safeguarding and protecting the ornamental horticulture industry, historical gardens and landscape plantings from boxwood blight.

This Best Management Practice document is a set of guidelines for home growers of landscape boxwood to avoid introduction of the boxwood blight pathogen into a landscape or, if the disease is already present in a landscape, to manage the disease in the most effective manner and avoid spread of the disease to new locations.

Since 2015, Extension specialists from Virginia Tech (VT) have visited and collected plant and soil samples from several large areas of dying great rhododendron (Rhododendron maximum) in Virginia’s mountainous regions. In 2016 VT specialists met with Virginia Department of Forestry, US Forest Service personnel, and other experts to revisit some of these sites. No consistent cause of this mortality has yet been identified. It is possible that a variety of factors are stressing the rhododendrons in these areas to a point where opportunistic pathogens or insects can successfully attack and kill them. The following information summarizes our observations and diagnostic results from four separate great rhododendron mortality sites in Virginia. This information is not equivalent to a research study, which would also include samples taken from healthy great rhododendron for comparison; however, we are confident that we have ruled out two diseases that are frequently mentioned both online and anecdotally as a cause of this mortality, specifically Phytophthora root rot and Botryosphaeria dieback.

Apple trees can produce plenty of fruits in the first two years of planting. If kept on the tree until harvest, these fruits would have a negative effect on tree growth and structure. Defruting newly planted and young apple trees (e.g., 2nd and 3rd leaf), particularly those on dwarfing rootstocks, allows the trees to fill their allotted bearing space and become structurally capable of bearing a decent crop by the fourth and fifth year. Although defruting can be achieved manually by removing flower clusters and small fruitlets, several chemical options can make defruting much faster and less labor-intensive. This publication aims to provide information about the rates and application timing of chemical materials apple growers can use to effectively defrut young trees.