2 JULIUS VALENTINE HOP MANN 



soon be of hemlock. The small seed of the cedar is a good example. 

 Although there is much seed of this species produced annually, the fact 

 that it is small, produces a small seedling, and requires exceptionally 

 favorable conditions for germination and establishment, limits the species 

 and prevents it from getting entire possession of the ground. 



In the Lake states, the jack pine (Pinus divaricatd) produces many 

 more seeds than the white pine (Pinus strobus] or the Norway pine (Pinus 

 resinosa), and these species are always in keen competition with one 

 another, resulting in the triumph of the jack pine in localities favorable to it. 



Periodicity of the seed years is variable; so much so that it can not be 

 considered in any practical application in planning for future forest work. 

 It must, however, be considered in determining when the latest heavy 

 crop of seed was produced. The forests produce seed sometimes 

 annually and sometimes at periods of two or three years or even more. 

 It is sufficient to know for the purposes of management, whether the latest 

 crop was a sparse, medium, or heavy one. 



In any average seed year, a forest furnishes enough seed to produce, 

 under favorable conditions, an adequate stand of seedlings. 1 The heavy 

 toll of rodents, fungi, drought, frost, and other unfavorable germination 

 conditions, however, reduces the number of seedlings resulting from a 

 single crop to a minimum. 



In regard to seed production Darwin says: "Large numbers of seed 

 are destroyed. The greater the chance against any given seed reaching 

 a suitable locality and attaining maturity, the larger the number of seeds 

 must the plant produce in order to maintain its numbers and as a general 

 rule the smaller will the individual seeds be. On the contrary the greater 

 the chance that each seed enjoys of arriving at maturity, the smaller the 

 number of seeds that is necessary, and in such cases it is an advantage 

 that the seeds should be large." 



DISTRIBUTION OF SEED 



Many species of coniferous trees bear seed with wings attached, being 

 thus adapted for wind distribution. Most of the seeds have a wing 

 attached to one side of the seed only. In an ordinary wind of ten or twelve 

 miles an hour, such seed when released from the cone begins a downward 

 spiral course and lands within 150 feet of the base of the tree. Since in 

 a large part of our coniferous forests there is usually little wind in the 

 p.utumn, or seeding time, wind can be considered a factor in seed distribu- 

 tion for only short distances from the seed trees. To be sure, the occasional 

 blast of wind at the higher altitudes, blowing at the rate of seventy-five 

 miles an hour, as has been measured by the writer in the Cascade 



f WCStern white pine " United Stales Department of Agriculture, 



