Conditions in urban environments place trees under numerous stresses including compacted soil, soil moisture extremes, and reduced soil fertility. Polluted air is another stress that contributes to the decline of urban trees. Air pollution may cause short-term (acute) damage, which is immediately visible, and long-term (chronic) damage, which can lead to gradual tree decline. Long-term damage may predispose trees to other disorders, making diagnosis difficult.

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.

Walnut is the common name given to twenty species of deciduous trees in the genus Juglans, of which six species are native to the United States. The black walnut, Juglans nigra, which is native to Virginia, grows from Maine west to southern Michigan and south to Texas and Georgia.

Hot landscape sites require special consideration before trees are planted. Trees can survive, and even thrive, in hot sites if the site is prepared correctly, if heat-tolerant species are selected, and if the trees are properly maintained. A variety of different locations and situations qualify as hot landscape sites.

Planting trees in aboveground containers and planters is becoming a common practice on sites that are not suited for inground planting. Containers differ from raised planters in that they are usually smaller in volume and moveable, whereas planters are generally larger, and often built as part of the permanent hardscape (paving, etc.). The greatest challenge in selecting trees for containers and planters is in choosing trees that can survive temperature extremes, and that can establish roots in a limited volume of substrate (potting soil). Consider several factors when selecting containers and trees including environmental influences, container and planter design, substrate type, and tree characteristics.

Aquatic plants are essential for a healthy and environmentally balanced water garden. Whether you are installing a new water feature or renovating an existing one, proper plant selection is critical. Plants compliment water features, soften hard edges, and add color, texture, and form. They also provide shelter and food for fish and other aquatic wildlife. The following steps will help you select and purchase aquatic plants.

A rain garden is a landscaped area specially designed to collect rainfall and storm-water runoff. The plants and soil in the rain garden clean pollutants from the water as it seeps into the ground and evaporates back into the atmosphere. For a rain garden to work, plants must be selected, installed, and maintained properly.

Small home pond gardens support aquatic plants and also attract a variety of wildlife. Turtles, frogs, birds, snakes, lizards, and raccoons as well as many other animals may use these ponds. Most wildlife needs water to survive and will seek out ponds for drinking, bathing, habitat, and in some cases, reproduction.

A watershed is an area of land that drains to a lake, river, wetland, or other waterway. When precipitation occurs, water travels over forest, agricultural, or urban/suburban land areas before entering a waterway. Water can also travel into underground aquifers on its way to larger bodies of water. Together, land and water make up a watershed system.

Water gardens require maintenance throughout the year. Preparation for the winter months is especially important for the survival of both the aquatic plants and the wildlife in and around the pond. Some plants will not tolerate winter weather and must be removed from the pond while cold-hardy plants need only to be completely immersed in the pond. Debris such as leaves and dying plants must be removed, especially if there are fi sh in the pond. Fall is the time to take action. Prepare the pond for the winter months by managing the plants, cleaning the pond, and monitoring the water conditions. If treated properly, many aquatic plants and wildlife can survive in the water garden for years.