The question of whether Redwood is a hardwood or a softwood often creates confusion because the common understanding relates to density and strength, while the scientific definition is purely botanical. Redwood lumber is known for its remarkable durability, leading many people to assume it falls into the hardwood category. This article clarifies Redwood’s true classification by examining the fundamental botanical differences and detailing the unique properties that give Redwood its impressive performance.
The Botanical Distinction Between Wood Types
The scientific classification of wood as hardwood or softwood is based on the type of tree the lumber comes from, specifically its reproductive structure. Hardwoods originate from angiosperm trees, which are flowering plants that produce enclosed seeds, such as those found in fruits or nuts. These trees are typically deciduous, meaning they shed their broad leaves seasonally. Conversely, softwoods come from gymnosperm trees, which are cone-bearing and have “naked” seeds, exemplified by most conifers.
Hardwoods are characterized by the presence of vessels, which are large, tubular cells that transport water and nutrients throughout the tree. Softwoods, in contrast, lack these vessels and instead rely on simpler cells called tracheids to perform the transport function. The presence or absence of these vessel elements is the defining characteristic distinguishing the two wood categories. This classification does not strictly correlate with physical hardness, as some softwoods like yew are harder than certain hardwoods like balsa.
Redwood’s Official Classification
Applying the botanical definitions, Redwood is officially classified as a softwood. This giant of the forest is a conifer, belonging to the cypress family, and therefore falls under the gymnosperm division. Like all softwoods, its wood structure is composed primarily of tracheids for water conduction, lacking the vessel elements that define a hardwood.
Despite its official status, Redwood’s physical characteristics can be misleading, contributing to public confusion. While Redwood is generally lighter and softer than many true hardwoods, its density profile, especially in the highly-prized heartwood, is sufficient to give it a surprising strength-to-weight ratio. The perception of it being a “hard” wood is likely less about its actual density and more about its exceptional longevity and performance in harsh conditions.
Performance and Durability of Redwood
Redwood’s reputation for toughness stems from its practical performance and durability, which often surpasses many true hardwoods in exterior applications. The heartwood contains high concentrations of natural organic compounds known as tannins. These tannins are responsible for the wood’s characteristic reddish-brown color and act as built-in deterrents against insect infestation and fungal decay.
This natural protection means that Redwood, particularly the heartwood grades, is inherently resistant to rot and termites without requiring chemical treatments. Redwood also exhibits excellent dimensional stability, which measures how well a material resists changes in size due to moisture fluctuations. It has one of the lowest volumetric shrinkage rates of any commercial domestic wood, meaning it is less prone to warping, checking, or splitting when exposed to the elements.
The combination of natural decay resistance and superior dimensional stability makes Redwood highly sought after for outdoor construction, such as decks, fencing, and siding. The practical longevity of these structures is what most people associate with quality, blurring the line between technical botanical classification and real-world durability. With a relatively low Janka hardness rating of approximately 450 pounds, Redwood is physically softer than woods like oak or maple, yet its superior performance in exterior settings explains the common misconception.