started by mid-September, peaked in late September and early October, 

 and was 98 percent complete by the end of November. Seed production 

 was influenced by stand density, an intermediate density producing far 

 more seed than the uncut control stand or the heavily cut stand. The 

 maximum seed fall per acre was 59 pounds (ovendry weight) of viable 

 seed. 



Methods and Materials 



Seed fall was measured twice — during a good seed year 1965) and 

 during a poor seed year (1968) — in a pure stand of white pine on the 

 Massabesic Experimental Forest. This even-aged stand of pine was 80 

 years old in 1965. We used three 5-acre plots of different densities — 80, 

 120, and 187 square feet of basal area per acre (table l). 



Table 1.— Average 



stand conditions 



in three 



white pine 



plots, 1965 







Average 



dominant tree measurements 



Stand-density 



Basal area 







level 



per acre 







Height in 





Height 



D.b.h. 



live crown 





Sq ft. 



Feet 



Inches 



Percent 



High 



187 



96 



17.1 



28 



Intermediate 



120 



95 



18.0 



36 



Low 



80 



101 



18.4 



40 



Seed fall was sampled in nine rectangular (l-x-2-foot) seed traps 

 randomly located in each of the three plots. The seed traps were emptied 

 at weekly intervals in autumn and at longer and less regular intervals in 

 winter. The collected seeds were cut longitudinally and examined. All 

 well-filled seeds with fully developed embryos were classed as viable. 

 Analysis of variance was used to evaluate the data, and orthogonal 

 comparisons were made to locate significant differences among the three 

 stand-density levels. 



Additional observations were made in 1965 to provide an indication of 

 total cone numbers and losses. Cone counts were made on 10 randomly 

 selected dominant trees in the intermediate stand. The observer made 

 binocular counts of mature normal cones and insect-infested cones in the 

 trees. Squirrel-cut cones and insect-killed cones on the ground were also 

 counted. 



2 



