Pinaceae
(Pine Family)
Habit
-
resinous,
monoecious trees
Leaves
- needle-like, spirally arranged
Female Cones
- usually woody,
scales spirally arranged
Ovules
- 2 on upper surface of
scale and subtended by a
united bract;
Pollen
- with
micky mouse
air bladders
Sperm
- delivered as
nuclei;
non-motile
Seeds
- usually 2 per
scale and usually
winged;
Embryo
- with several
cotyledons
Diversity
- 9 genera / ca. 200 species
Distribution
- northern hemisphere
Economics
- important sources of timber and
pulp,
turpentine,
resins, cultivated ornamentals and edible seeds.....
Must know genera:
-
- Abies (Fir): 39 spp./N. Temperate--2 spp. in Arizona; leaves borne on branches without
short shoots, those on
laterals twist into horizontal plane;
female cones mature in 1 year and are erect on branches and have deciduous
scales; utilized for wood and one species (A.
balsamea, N Am.) source of Canada balsam used in microscope preparations and Christmas tree. (Monograph in
Taxon, 1971 by S. Liu)
- Picea (Spruce): 34 spp./N.Hemisphere--2 spp. in Arizona; persistent raised leaf-bases & pendulous woody female cones with persistent scales that mature in 1 year; important softwood used in hardboard, as pulp, cellophane & rayon, and 1
sp. (P. abies) common Christmas tree. (Revised in Phytologia M. 7:43. 1984)
- Pinus (Pine): 93 spp. /N. Temperate to Central America--9 spp. in Arizona; Scale leaves on long shoots soon lost and long needle leaves in clusters of 1-5 on short shoots subtended by scales; female cones woody, mature in 2-3 years; m
ost important timber in temperate and tropical regions, timber, pulp & resinous products like turpentine and
rosin (used to size paper), seeds edible--pignolas
or
pignons; Subgeneric marker is number of vascular bundles in the needles (sect. Strobus "soft pines" have 1 & sect. Pinus "hard pines" have
2). (Revised in Phytologia M. 7:47. 1984)
- Pseudotsuga (Douglas fir): 4 spp./East Asia and W. N. Am.--1 sp. in Arizona; allied to Picea but with conspicuous bracts between
cone-scales; our species (P. menziesii) was also named P. douglasii hence the common name; major timber tree, used for plywood, pulp, source of Oregon balsam. (Review in Phytologia
M. 7:70. 1984)
Others:
-
- Larix (Larch or Tamarack): 9 spp./cool N. Hemisphere; deciduous.
- Tsuga (Hemlock): 10 spp./temp. N. Am. & E. Asia; important timber and cultivated.
- Cedrus (Cedar): Cedar 2 spp./N. Africa & Asia; cultivated.
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