San Diego Natural History Museum--Your Nature ConnectionSan Diego Natural History Museum Biodiversity Research Center of the Californias: Botany Department


Plant Atlas
Climate Change
The Collection

Field Guide

Natural History of Holiday Plants Exhibit
Evergreens | Holiday Color | Poinsettia | Holly | Mistletoe
Christmas Cactus | Christmas Tree | Common Holiday Plants

Christmas Tree

Abies concolor, photo courtesy of Norm Roberts Scientific name(s): various species of Abies, Pseudotsuga, Pinus, Juniperus, etc.
Plant family: usually Pinaceae-Pine Family or Cupressaceae-Cypress Family
Other common names: tanenbaum; or fir, pine, cedar, etc. depending upon the species

Many species of conifers are used as Christmas trees, with the choice of species for any household being influenced by personal choice and by what trees are available locally. The first Christmas trees were probably firs (Abies), but now in the United States, Douglas Fir (Pseudotsuga menziesii), pines (Pinus), cedars and junipers (Juniperus) may be used. However, there are many alternative choices to these conifer species depending upon local tradition and the region where you live. Even mesquites (Prosopis), century plant stalks (Agave), Elephant Trees/Torotes (Bursera), rosemary (Rosmarinus officinalis), and plastics (artificial trees) have been used.

What do Christmas trees and local drought-tolerant shrubs have in common?

Eriogonum fasciculatum, photo courtesy of Norm Roberts Most Christmas trees are cone-bearing (conifer) plants that frequently have modified leaves that we refer to as needles. These needle-like leaves have various adaptations like thick, waxy outer layers that help the plant to conserve water, and resin canals that help to protect the leaves from damage due to cold, icy temperatures. In general, evergreen plants in temperate climes must have various survival adaptations in order to cope with more than one type of environmental stress. Like ornamental Christmas trees, many of our local evergreens including Chamise (Adenostoma fasciculatum), Buckwheat (Eriogonum), and our mountain conifers have adaptations to help retain water during the unfavorable times of the year, such as winter at high elevations and dry summers near the coast in our Mediterranean-type climate.

Text by Jon P. Rebman, Ph.D., Curator of Botany;
Abies concolor, top, and Eriogonum fasciculatum (Buckwheat), bottom,
photos courtesy of Norm Roberts