The mulch/area interaction was highly significant (p = .01) in 1962 (fig. 2). 

 Although seedling survival on Area 2 was higher under a straw mulch than under no mulch, 

 the situation was reversed on Area 1. A tentative inference is that mulching on the 

 deeper soils helps conserve enough moisture to improve survival. It doesn't help on 

 shallower soils because the reservoir of moisture just isn't large enough to meet normal 

 evapotranspiration demands and nevsf seedling demands too. By 1966 this mulch/area inter- 

 action had decreased but was still significant (p = .05). 



A highly significant mulch/site-preparation/area (3-way) interaction was present in 

 1962 (fig. 2). By 1966 this 3-way interaction had lost all significance. 



The extent of terminal damage over the 6^ years became evident when the seedling 

 heights were measured in October 1968, seven growing seasons after planting (Appendix 

 III). On Test Area 2, 82 percent of the seedlings alive at the time of height measure- 

 ments showed terminal damage; on Test Area 1, 58 percent showed terminal damage. The 

 damage to most stems was of the type ascribed to hares (Lawrence, Kverno, and Hartwell 

 1961). Deer and elk were probably the next most important causes of damage. Such 

 depredations were probably responsible for some seedling mortality as well. There did 

 appear to be a correlation of soil depth with percent of seedling damage (fig. 3). 

 Seedlings on deeper soils, growing more vigorously, may have had tissue that was more 

 succulent, or less resinous, or perhaps they were associated with a greater quantity 

 of edible plants tending to concentrate animals and giving an increased probability 

 for browse damage. 



200 - 



190 



180 



ir 

 O 



z 

 < 

 cc 



170 



160 



150 



140 



SCALPS 



^ FUR 



ROWS 



PITS 



MULCH NO MULCH 



TEST AREA 1 



MULCH NO MULCH 



TEST AREA 2 



Figure 2. — Interactions between mulahesj site -prepccration, and areas ^ 1962. 



