Other obvious differences reflected by the curves in figure 3 are the time inter- 

 vals for germination. Even though the rates may have been similar, germination may have 

 occurred at later dates, thereby not permitting as long a growing period as first-season 

 seedlings might need. The opening-cleared and opening-natural seeds germinated earliest 

 with the opening-litter, the fire, the near, the litter, and the stemflow seeds appear- 

 ing about 1 week later. The canopy and natural treatments created situations in which 

 germination was 3 to 4 weeks behind the other treatments. This caused the average seed- 

 ling age at the end of the growing season to be only 19.7 weeks for the canopy seedlings 

 and 17.2 weeks for the natural seedlings compared to an average of 22 weeks for the 

 other seven treatments. 



Looking at replications within the natural, the near, and the fire treatments, 

 those plots with the greatest overhead canopy had the slowest and latest seed germina- 

 tion. Reasons for this are probably the same as for the variation in total germination: 

 differences in temperature, moisture, and perhaps light. 



Seedling Mortality 



A total of 1,323 seedling deaths were recorded during the 1975 growing season. 

 This represents 27.5 percent of the seeds that germinated. The percent mortality ranged 

 from 56.6 to 12.7 (fig. 4). The stemflow and litter treatments suffered the greatest 

 damage, losing over half of their seedlings. The next six treatments all had very 

 similar losses, 21 to 29 percent, while the opening-cleared treatment averaged only 

 12.7 percent. The average seedling mortality on the three opening treatments was 21.0 

 percent which was significantly lower at the 5 percent level than the 35.3 percent 

 loss for the pine-influenced treatments. 



Cutworm activity resulted in the greatest number of mortalities, more than 30 per- 

 cent, and was most prevalent in the litter treatment causing more than 61 percent of 

 the seedling deaths (table 4) . Other treatments that were substantially affected by 

 cutworms were the opening-litter, the opening-natural, the fire, and the stemflow. The 

 only treatments which did not have significant cutworm activity were the opening- 

 cleared plots due to lack of protective ground cover and the natural plots because the 

 seeds germinated very late in the growing season, after larval activity had declined 

 considerably. Although damage caused by these insects was observed on pine-associated 

 treatments where the ground cover had been removed, their greatest influence appeared 

 where ground cover was present. 



The second most important cause of seedling death was cotyledon clipping due 

 apparently to birds and small mammals. The treatments whose seedlings were most sig- 

 nificantly affected by this category were the stemflow, the opening-natural, and the 

 canopy. The near treatment showed rather high clipping mortalities (table 4) , but 95 

 percent of these occurred in only one of the three replicate plots, so it was not a 

 general trend. The fences were apparently only a partial deterrent to small mammal 

 activity and were no obstacle for birds. 



Seedling deaths caused by cutworms, and small mammals and birds were similar in 

 that a portion of the seedling was severed. These two mortality t)TDes may be distin- 

 guishable by the region of the seedling receiving the injury. Cutworms apparently 

 sever the stem near ground level, whereas mammals clip a portion of the cotyledons, or 

 the upper stem directly below the cotyledons. Birds likely pluck the seed coats when 



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