Science / Biology / Stomata: Pores on the underside of leaves that can be opened or closed to control gas exchange and water loss. Openings in the epidermis (usually of the leaf) that allow gas exchange.

Stomatal Apparatus

Science / Biology / Stomatal Apparatus: The stomata and guard cells that control the size of the stoma. MORE

Noble Fir

Life Style / Christmas Trees / Noble Fir: In the wild, the trees are tall, beautifully symmetrical and grow to over 200 feet in height. The bark is smooth with resin blisters when young and changes to brownish-gray plates with age. The needle MORE

Scotch Pine

Life Style / Christmas Trees / Scotch Pine: Scotch or Scots pine is an introduced species which has been widely planted for the purpose of producing Christmas trees. It is an extremely hardy species which is adaptable to a wide variety of soils MORE

Grand Fir

Life Style / Christmas Trees / Grand Fir: The grand fir is one of the tallest firs, reaching heights of 300 feet. It is easily distinguished from other Pacific Northwest firs by its sprays of lustrous needles in two distinct rows. They are us MORE

Balsam Fir

Life Style / Christmas Trees / Balsam Fir: First described in 1768, balsam fir is a medium-sized tree generally reaching 40-60 feet in height and 1-1 1/2 feet in diameter. It exhibits a relatively dense, dark-green, pyramidal crown with a slen MORE

Xerophytic Leaves

Science / Biology / Xerophytic Leaves: The leaves of plants that grow under arid conditions with low levels of soil and water. Usually characterized by water-conserving features such as thick cuticle and sunken stomatal pits. MORE