14 THE WESTERN HEMLOCK. 



DEMANDS UPON SOIL AND MOISTURE. 



The Hemlock ranges from mucky swamps to rocky hillsides. It 

 requires, however, a heavy rainfall and Is seldom found where the pre- 

 cipitation averages less than 40 inches annually, reaching best devel- 

 opment where it is above 70 inches. The finest Hemlock in Washing- 

 ton grows at an altitude of 2,000 to 3,500 feet on the western foothills 

 of Mount Rainier, where the annual precipitation is seldom less than 

 80 inches and snow lies half the year. 



REPRODUCTION. 



A prolific seeder and not fastidious as to seedbed, Hemlock repro- 

 duces freely under a wide range of conditions. In the drier inland 

 regions, or where the soil has been severely burned, it does not rival 

 Red Fir, but on the coast it far excels it. While Fir prefers a bare 

 mineral soil. Hemlock reproduces better on a humus of leaves or rotten 

 wood. (Pis. IV, V.) Stumps and fallen logs form a favorite seed- 

 bed, and large trees are often seen standing on leg-like roots, which, 

 starting from the log or stump, have extended downward to the ground, 

 finally to be left unsupported by the decay of their host. (PI. IV, 

 fig. 1.) Hemlock is thus enabled often to seed up ground where there 

 is sufficient light for the germination of Fir. Insects, wind, or a 

 ground fire may cause a tangle of fallen timber, later covering the 

 ground with rotten wood. A few fires may start under such condi- 

 tions, but Hemlock is likely to get the mastery. Near South Bend, 

 Wash., is an illustration of this on a large scale. About sixty years 

 ago the standing timber on a tract covering nearly a township was 

 destroyed. No sign of fire is visible. Appearances indicate that 

 this destruction was wrought by the measuring worm, which has since 

 attacked large areas of Hemlock along the coast, notably near Grays 

 Harbor and in Oreo-on. The original stand was chieflv Hemlock and 

 Spruce; now, almost rotten, it covers the ground 1 to 2 feet deep. 

 A few seed trees survive the catastrophe and record its date clearly 

 by two or three very close rings, showing slow recovery from the 

 injury, followed by greatly accelerated growth due to the increased 

 light. Although there was an abundant supply of Red Fir seed, none 

 germinated, and 90 per cent of the young growth now standing is 

 Hemlock, with an occasional Spruce or Cedar. The Hemlock is of 

 very rapid growth, averaging over 100 feet high and 13 inches in 

 diameter at 55 years of age. 



Hemlock bears seed almost every year. The age at which seed bear- 

 ing begins varies with the amount of light in which the tree has grown. 

 Trees coming up in burns may bear when 25 or 30 } T ears old, but those 

 which have grown in the woods do not bear until much later. The 

 seeds, like those of most conifers, are winged and may be carried great 

 distances by the wind. 



