Certified Arborist Practice Test

Ring porous tree species are characterized by having large vessels, or pores, that are produced in the early growth season, followed by smaller vessels in the late season. This structure can result in distinct annual growth rings in the wood. Among the trees listed, oak is a well-known example of a ring porous wood, exhibiting this marked difference in vessel size from the early to late growth periods. Elm also displays ring porous characteristics, though it is less universally recognized as such compared to oak. Ash, while it may not be the first tree that comes to mind when discussing ring porous types, can also exhibit similar growth patterns. Thus, all the tree species mentioned—elm, oak, and ash—fall under the category of ring porous species. Each has the capacity to showcase the distinctive banding of large early vessels followed by smaller ones, which is the hallmark of ring porous structure. Therefore, the answer encompasses all listed species accurately reflecting the characteristics of ring porous trees.