California Structural Pest Control License – Branch 3 (General Pest) Practice Exam

Brown rot is a specific type of wood decay that primarily affects the cellulose and hemicellulose in wood, leaving behind lignin, which gives it a distinctive appearance and texture. A key feature of brown rot is cross-grain cracking, which occurs as the wood shrinks and loses strength due to the degradation of its structural components. This cracking often appears as a series of small, jagged splits that run across the grain of the wood, indicating that the integrity of the wood has been compromised.

The presence of high moisture content or bright coloration is not typically associated with brown rot. Instead, brown rot often results in a dry and crumbly texture as the wood decays, which can be misleading if one is looking for signs of color or moisture. Uniform texture is also not a characteristic of brown rot; typically, the decay leads to a more fragmented or uneven surface. Thus, cross-grain cracking serves as an important indicator of brown rot in wood, highlighting the damage caused by this type of fungal infestation.