Sugar pine was 'discovered' by David Douglas of Douglas-fir fame. The name of the tree is derived from the sweet resinous substance that is found within the bark and wood. John Muir is said to have preferred the sap from sugar pine over that of maples (Schoenherr 1992).
Sugar pine holds an important place in the history of California. Historians claim that John Sutter's Mill in Coloma, California, the site of the first gold spotted that in turn spurned the California gold rush, was built to process sugar pines for logs to be used in construction in the area (Schoenherr 1992).
Sugar pine is the tallest of all pines, often reaching heights of 61m (200ft.) and widths in excess of 3.5 m. Currently, the California state champion measures 216 ft. tall with a circumference at 4 1/2 ft. of 384 inches (Bronaugh, 1991). In addition to being the very tallest of the pines, sugar pine is one of longer lived of the pines. Sugar pine can live up to 500 years (Kinloch and Scheuner 1990).
Sugar pine can be identified from a distance by the open, narrow, and flat-topped crown with long horizaontal branches that, from a distance, can be seen drooping at the ends due to the weight of the cones clustered at the ends of the branches (Kinloch and Scheuner, 1990). Sugar pine is also easily distinguished by its silvery-lined bluish green needles, clustered five to a fascicle and 7-10 cm in length with several rows of obvious stomates on both sides of the needle. Overall, the needles appear short and stiff and give the sugar pine the appearance of having furry arms when looked at from a distance. The branches are said to be reminescent of long tarantual arms, extending outward from the tree (Schoenherr 1992).
Bark is resistent to low and moderate intensity fires. The bark is very thick and is divided into irregulary furrowed plate like ridges with loose redish brown scales (Hickman 1996).
Cones are the longest cones in the world and may exceed 2 feet in length (Bronough 1991, Hickman 1992). Becasue the cones hang on the ends of the long and sweeping branches, it is almost impossible for large seed eating birds to make a meal of the seeds. Despite this, loss of sugar pine cones is heavy; predation by the sugar pine cone beetle (Conophthorus lambertianae) can cause up to 93 percent loss (www.forestworld.com). McDonald (1992) found that although sugar pines produce significant crops every three years, over 50 percent of the seeds produced are unsound. Douglas squirrels (Tamiasciurus douglasii) and white-headed woodpeckers (Picoides albolarvatus) also take a heavy toll (Johnston 1994).
Sugar pine is monoecious. Cones begin development in July or August, but are not obvious until late spring. Pollination occurs in late May to early August. Fertilization does not occur until late in the following spring, about 12 months after pollination. Cones open in mid-August at low elevations and in early October at higher elevations (www.forstworld.com). After almost 2 years, the seeds are released from the cones. Seeds are large and heavy (2,100/lb). Wings are small compared to the size of the seeds and are thus not disperesed far from the parent plant. Most seeds will fall within 30 m of the parent tree. Many animals such as the sugar pine cone beetle, Douglas squirrel and white-headed woodpecker consume or cache these seeds and only up to 40 percent of the seeds develop into seedlings. Birds and small mammals are important dispersers of sugar pine seeds. Despite the fact that most seeds collected are eaten, these animals provide a crucial mechanism for the widespread dispersal of the sugar pine's seeds (Johnston 1994).
The natural range extends
from Oregon to Mexico and east to Nevada, but over 80 percent of the growing
stock is in California. Sugar pine is found at mid elevations in the Klamath,
Siskiyou, Cascade, Sierra Nevada, Transverse, and Peninsular Ranges of
California. Elevations of sugar pine range from near sea level to
over 3000 m (10,000 ft.) (Kinloch and Scheuner 1990). It rarely forms
pure stands. It is an early to mid seral species. It is a major
component in mixed Conifer, douglas fir, ponderosa pine, lodgepole pine,
redwood, and chapparral communities. This species generally comprises 5-25
% of the cover in these associations. It is found as a minor component
in Red fir, white fir, Padific Douglas fir, and Canyon Live Oak dominated
forests (Barbour and Billings 1988). In the northern mountains some of
its associates include Douglas-fir (Pseudotsuga menziesii), ponderosa
pine (Pinus ponderosa), grand fir (Abies magnifica) and incense
cedar (Calocedrus decurrens). In the Sierra it is found with Jeffrey
pine (Pinus jeffreyi), giant sequoia (Sequoiadendron gigantea),and
California Black oak (Quercus kelloggii). In fact, the most dense
populations of sugar pine are found on the western slopes of the Sierras.
In the southern mountains sugar pines grow with Ponderosa pine (Pinus
ponderosa), coulter pine (Pinus coulteri), white fir (Abies
concolor) and incense cedar. Common understory associates include
Ceanothus
spp. (CA lilac), Arctostaphylos spp.(manzanita), and Cercocarpus
ledifolius (mountain mahogany) (Barbour and Billings 1988).
Sugar pines are adept at growing in a variety of temperatures and precipitation levels. Despite this, sugar pines succeed best in areas with relatively warm temperatures that experience dry summers and cool and wet winters (Hickman 1992). Most precipitation occurs between November and April, as much as two-thirds of it in the form of snow at middle and upper elevations (Barbour and Major 1977).
Sugar pine grows in a wide range of soil conditions. Parent materials include volcanic rock, granite, sedimentary and metamorphic rocks. Sugar pines are often found to be dominate on more mesic sites within its range. Sugar pines also tend to be found in areas with well drained, permeable, and slightly acidic soils that consist of sandy to clay loams. As a result of its soil requirements, sugar pines tend to be found on soils within the orders Ultisols and Alfisols (Barbour and Major 1977).
Sugar pine is considered a very important timber species due to the quality and value of its soft, even-grained wood (Ibid).
In the past, sugar pine was important for indigenous peoples, who used the seeds and bark for food, the rootlets for baskets, the pitch for glue and gum, and the leaves and bark to make medicinal teas (Clarke, 1977). John Muir found its sweet resin preferrable to maple sugar (Bronaugh, 1991). Indians ate the sugar pine sap and also used it as a laxative. Native Americans also used the pitch from the sugar pine to repair canoes and to fasten arrowheads and feathers to shafts. Native Americans also harvested and ate the seeds from the cones (Schoenherr 1992).
Although sugar pine is ozone tolerant (Fenn, 1991), it is not very drought tolerant, which makes it more difficult to plant than other pines. Among conifers, sugar pines are the most tolerant to oxidant air pollution, while intermediate in fire and frost resistance. The sugar pine is also less tolerant to drought than most conifers. Sugar pine is declining due to its high suceptibility to white pine blister rust, a disease that infects seedlings and kills them as cankers girdle the main stem. Natural regeneration is thus curtailed in heavily infected areas. Introduced at the turn of the century in Oregon, white pine blister rust began infecting northern California sugar pines sixty years ago, where the intensity of infection still remains the highest (Kinloch and Scheuner, 1990).
Much of the literature about sugar pine is focused on this problem. A small percent of the trees carry resistance genes and work is underway to further develop blister rust resistant stock under the auspices of the California Sugar Pine Program (Kitzmiller, 1991). Other techniques to reduce disease in plantation stock are also being investigated (Jenkinson and McCain, 1993). In the meantime, increasing scarcity of high-grade sugar pine trees has led to an increase in timber value (Willits and Fahey, 1991).
Today impressively large sugar pines can be seen growing in Calaveras Big Trees State Park. Wandering around the magnificent groves, you can understand why John Muir called sugar pine the "Queen of the Sierras" (Bronaugh, 1991)..