Black Twig Borer (Xylosandrus compactus)Latin Name: Xylosandrus compactus
Common Name: Black Twig Borer
Appearance:
Adult females have a robust, cylindrical, elongate body that is dark to black with conspicuous punctures on the posterior pronotum, a transversely oriented hair tuft at the base of the pronotum, and lengthy strial setae.
Adult male length 0.8-1.1 mm, breadth 0.4-0.5 mm; body rounded, dwarfed, reddish-brown; all features poorly developed; flightless and scarce Small (0.3 mm diameter x 0.5 mm length), white, oval egg.
Mature larvae are around 2 mm long, with a pale brown head capsule, a creamy white body, and no legs.
Pupa length is comparable to adult; the body is creamy white; the shape is exarate.
Host plants:
Xylosandrus compactus, often known as black twig borers, drill into the thin twigs of dogwood, grape, magnolia, live oak, laurel oak, and many other plants ranging from shade trees to orchids. Plants that appear to be healthy are attacked. Twigs and stems that are infested will wilt and perish. A young tree is more vulnerable to infection.
Territory:
The black twig borer was initially discovered in the United States in 1941 in Ft. Lauderdale, Florida. Its distribution has expanded northward to Tallahassee and Savannah, Georgia, by the mid-1970s. The current distribution in the Southeast runs from Texas to North Carolina along the Coastal Plain. This beetle may also be found in Hawaii. Brazil, Cuba, Indonesia, Japan, and Sri Lanka are among the countries where it may be found.
Damage caused by Black Twig Borer:
Adult beetles also transport spores of a fungus (Fusarium solani), a disease of trees, into the galleries of their host trees. As it spreads, the fungus plugs the tree’s xylem tissue, causing withering and death.
Life history and Habits:
Adult beetles are most active in the early spring. However, harsh winters may lower black twig borer numbers or inhibit insect development. Adult beetles spend the winter afflicted tree twigs and branches, and adult females emerge around the time dogwoods blossom. Females then re-enter fresh twigs and tiny branches to establish brood chambers or galleries in the stem pith and lay eggs. The life cycle (from egg to adult) within the host plant takes roughly 28 to 30 days. All phases of the beetle are observed within their galleries during the spring; 10 to 15 beetles can develop a single gallery.
