CONTENTS 



Page 



INTRODUCTION 1 



SITE PREPARATION, MULCHING, AND ASPECT TESTS (ZENA CREEK) 3 



Test 1: Pits, Furrows, and Scalps, With and Without Straw Mulch, 1962 ... 3 



Test 2: Burned Spots and 2-, 4-, and 6-Foot Scalps on Two Aspects, 1962 . . 5 



Test 3: Pits and Synthetic Mulches on Two Aspects, 1963 6 



Test 4: Pits, Synthetic Mulches, and Simazine on Two Aspects, 1964 9 



SOIL MOISTURE AND TEMPERATURE RELATIONS (BOISE BASIN) 12 



Test 5: Soil Moisture and Temperatures Associated With Undisturbed 



Spots and Pits, With and Without Synthetic Mulches, 1964 12 



SUMMARY AND CONCLUSIONS 19 



RECOMMENDATIONS 20 



LITERATURE CITED 21 



APPENDIX I~Soil Depths on Regeneration Plots, Test 1 22 



APPENDIX II~Survival (Percent), Tests 1 Through 5 23 



APPENDIX III — Mean Heights of Seedlings by Terminal Condition Class, 



1968, Test 1 25 



APPENDIX IV — Soil Moisture Content (Percent) at 1/3 and 15 Atmospheres, 



Test 5 26 



APPENDIX V~Periodic Monthly Soil Moisture Content Under Four Mulch 



Treatments at Three Depths, Test 5 27 



APPENDIX VI — Analysis of Variance Table for Seedling Survival, 



1964-1968, Test 5 28 



ABSTRACT 



Site preparation and mulching tests were carried out on some steep slopes 

 having shallow soils in the Douglas-fir — Ninebark habitat type on the Boise 

 and Payette National Forests. Treatments included: (1) hand scalping; (2) a 

 herbicide; (3) spot burning; (4) periodic hand weeding; (5) straw mulch; (6) black 

 plastic film mulch; and (7) glass fiber mulch. Other natural variables recog- 

 nized were: (a) aspects; (b) soil depth; (c) moisture relations; (d) summer rain- 

 fall; (e) temperatures above undisturbed vegetation and above surfaces of 

 treatments (4), (6) and (7). Survival and 5-year height growth of the outplanted 

 2-0 nursery stock were measured. Extensive mammal damage was noted and 

 appeared to be indirectly correlated with soil depth. All treatments increased 

 seedling survival. Observations suggest that combining hand scalping and 

 herbicide is most promising in terms of cost and effectiveness. Height growth 

 was positively correlated with plot survival percent and soil depth. Trees 

 were tallest where black plastic film was used and on SE aspects; such growth 

 was probably related to the influence of warmer temperatures. 



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