La Placa Exterminating Inc

Subterranean Termites

Subterranean termites are the most destructive insect pests of wood in the United States. They cause more than $2 billion in damage each year, more property damage than that caused by fire and windstorm combined.

    In nature, subterranean termites are beneficial. They break down many dead trees and other wood materials that would otherwise accumulate. The biomass of this breakdown process is recycled to the soil as humus.

    Problems occur when termites attack the wooden elements of human structures -- homes, businesses and warehouses. Their presence is not readily noticed because they hide their activity behind wallboards, siding or wood trim.

Control measures include reducing the potential for subterranean termite infestation, preventing termite entry, and applying residual chemicals for remedial treatment.

Inspection

    Thorough inspections can determine whether infestations and damage are present, whether remedial control measures are needed, and what conditions can encourage termite attack. Inspections can be performed by anyone who knows the basic construction elements, the environmental requirements for termite survival and the behavior of subterranean termites.

    Tools and equipment needed for an inspection include a flashlight, ice pick or sharp-pointed screwdriver, ladder and protective clothing (bump cap, coverall, rubber knee pads). A clipboard, graph paper and floor plan or sketch help in recording inspection findings accurately and ensuring that the entire structure has been examined. A moisture meter can often detect increased moisture levels in the shelter tubes hidden behind walls, as well as high moisture conditions that encourage subterranean termite infestations.

Where to check outside

• Examine the foundation of the house, garage and other structures for shelter tubes coming from the soil.
• Pay particular attention to attached porches, connecting patios, sidewalks, areas near kitchens or bathrooms and narrowly confined or hard-to-see places.
• Check the soil moisture around or under the foundation to determine if faulty grade construction creates moist areas next to the structure.
• Check window and door frames and where utilities (air conditioning pipes, gas and electric services) enter the structure for termite infestation or wood decay.
• Observe roof eaves and guttering closely for defects that might cause leakage and eventual wood rot. Inspect behind closely planted, dense shrubbery or foliage.
• Note particularly any earth-to-wood contact such as fences, stair carriages or trellises.
• Open and examine any exterior electrical meter or fuse boxes set into the walls, a common point for infestation.
• Carefully inspect wood materials next to swimming pools that may be splashed frequently by water.

Additional Details

http://insects.tamu.edu/extension/bulletins/b-6080.html

http://www.pestweb.com/

More Information

Dead trees and brush are the original food source of subterranean termites. When land is cleared of this material and houses are built on these sites, termites attack the structures. Termites can enter buildings through wood in direct contact with the soil, by building shelter tubes over or through foundations, or by entering directly through cracks or joints in and under foundations.

    Any material in direct contact with the soil -- such as trees, vines or plumbing fixtures -- serves as an avenue of infestation. Subterranean termite swarmers may also be blown into or on structures and then start a new colony.

Signs of infestation

    The presence of swarmers, wings or damaged wood signals that termites are infesting a structure.

    Swarmers: Generally, the first sign of infestation noticed by homeowners is the presence of swarming reproductives on window sills or near indoor light. Swarmers inside the house nearly always indicate an active infestation in the structure. The presence of swarmers outdoors is a natural phenomenon, but should warn that termites are near and possibly attacking a nearby building.

    Wings: Another indication is the presence of wings, discarded by swarmers as a normal part of their behavior, found near emergence sites, on window sills or in cobwebs. Infestations also can be detected by the presence of shelter tubes going up the sides of piers, utility entrances or foundation walls.

Where to check inside

• Probe or carefully sound exterior porches, doors and window facings, baseboards, and hardwood flooring. Be careful not to deface finished wood when probing.
• Carefully examine any attached earth-filled porches.
• Examine all known or suspected joints, cracks or expansion joints in the foundation and unusual blistering in paint or wallboard surfaces. Discoloration or staining on walls or ceilings may indicate water leaks that can decay wood and aid termite infestation. Especially inspect where plumbing or utility pipes enter the foundation or flooring.
• Check the floor covering for raised or split areas.
• Carefully examine the plumbing, particularly in bathrooms on slab construction. There should be access to the bath trap area. If none exists, build a removable plumbing hatch for periodic inspection.
• Examine the attic for shelter tubes, water leakage, wood rot or damaged wood.
• If the house is of pier and beam construction, thoroughly inspect the area between the floor and the underlying soil (crawl space) (Fig. 5). Examine the inside of the beams, chimney bases, hearths or piers for shelter tubes. Crawl-space construction should have a minimum of 18-inch clearance between floor joists and the underlying soil, and a least 12 inches between floor beams and the soil.
• Examine areas underneath or close to earth-filled porches, patios, planters and bathrooms for water leakage and termite damage. Remedial action may be required to control moisture if water stands under-neath the house.
• Look carefully at the top of the foundation wall where the floor and the wall intersect.
• Closely examine plumbing and utility lines passing through the floor of foundation walls.