Subkingdom III. Achloronta
The plants described in this atlas are two of the above groups, the Division 11 Coniferophyta (Pinophyta) and the Division 13 Anthophyta (Magnoliophyta). Two examples of the Division 13 is as follows:
or Mock Orange Idaho
(The state flower)
|White Pine or Western White Pine (the State Tree)|
The Class Pinopsida includes mostly trees, such as hemlocks, firs, spruces, larches, and redwoods, but also includes shrubs such as junipers and Japanese yews. Their leaves are simple, often scale-like or needle-like. The leaf bases are not persistent. The wood (xylem) is compact, composed mostly of tracheids, with narrow rays. The pith and cortex are restricted, thus the xylem makes up the majority of the stem. The stem is often differentiated into long portions and short spur shoots. From the stem, the vascular tissue (leaf traces) into the leaf may be one or just a few. The ovules are most often borne in compound cones (strobili) or the ovules may be borne singly.The pines, or their relatives, may be and often are the dominant type in many forested regions in northern Idaho or in ravines in southern Idaho. Many are valuable for lumber, manufacture of paper, or for naval stores. Some may reach ages up to 4600 years. The leaves are evergreen with the exception of larches, which lose their leaves in the fall. Growth is seasonal and periodic, depending upon temperature and moisture availability. There are two kinds of leaves-the obvious needles and the less obvious scale leaves which occur on the main branches and bases of the needles. The needles in the pines are borne singly in one Idaho species, the singleleaf pinion pine, but most often in 2's, 3's, or 5's. In the other conifers, the needles are borne singly. Moisture loss is prevented by a heavily cutinized epidermis and wax coating. The trunks and branches increase in diameter by cell division in the cambium layer, which is cylindrical. Cross sections of the stems reveal concentric circles caused by thin-walled cells in the spring growth and thicke-walled cells in late season growth. Reproduction results from a combination of pollen produced in small ephemeral cones and ovules produced in the more obvious woody cones. Both occur on the same tree or shrub. The ovules are commonly borne in pairs on the upper surface of the cone scales. Some, because of their large size, are considered edible to humans, such as pinion pine nuts. The seeds of most genera and species are eaten by mammals and birds.