TVF"] OF rORllST AFF3CTS "^LDLIF^^ 



Compared mth other parts of a dens? forest> the floor is prac- 

 tically devoid of animal life. Fe'e animals can vtilize it for a per- 

 •'manent home. Food is scarce , and— s-helter is scant. On such a forest 

 ■ the only forms present in any. abundance are those capable of arboreal 

 'life. Chickadees (Penthestes ), nuthatches (S itta ) , pine squirrels 

 (Tamia sciurus )j- gray sqrirr'3ls (Sc iuru s) ^ and a few chipmunks (Eutamia^s) 

 frequent ths treetops. The more-open forests, as those of the' ponde'rosa 

 • pine (Pinus ponderosa). of the '"'-st, are more hospital l;i to I'^ildlife. Jx-* 

 cept in dens? reproduction thickets, the traes are, so s'pacsd tha't sonie- 

 light reaches'the forest floor. Grasses and herbaceous vegetation thrive 

 in proportion to the o'penness' of tha canopy, -'lera snail . rodents exist 

 in sonev'hat greater abundance, and birds and the larger mammals, includ- 

 ing the fur bearers and deer, in notably larger numbers. The' sugar pine-- 

 fir tjrpe of the Sierra Fevadas seems int:^rmediate in wildlife carr- ' ng 

 capacity. In this kind of forest in California, sugar pine (pinus 

 lam^bertiana) is not reprc>.lucinj- on many large areas, Inst^ad> v/hite 

 fir (Abies concolor ) and incense cedar (Liboc5di-us decurrens; predom- 

 inate in thj reprodiiction* 



, Op any forest, disturbances of catastrophic* proportions', as* 'turn- 

 ing or cutting, caus3 abrupt changes in thi biotic corariunity. This yras 

 obs'jrved in California forests* - Follovdng logging on thf; sugar pin3-fir 

 type, the ground cover increased rapidly* Herbaceous specr.-s, as grass'is, 

 shrubs, and especially.' bur-clovir (Chamaibatia foliolosa), grev/ abundant- 

 ly, thj bur-clove 1- formin^^^ a tonacious mat on the ground. The habitat 

 was vastly improved for small rodents and m.ice (F iromy scus sp, and Ficrotus 

 m.ordax), and chipmunks incrjasrd from 10 to 50 fold* ■ 



As such an area grovs up to brovrs species ^ deer ( Odocoiljus 

 hemionus ) find it suitable for summer pasture* "'inter range of deer in. 

 this area is mor"^ of a restrictive factor than summer range, and manage- 

 m.ent th'-t produces additional summer range should also provide th'j sup- 

 plementary vi-nter range that yrill inevitably b,"; needed. In a few jrears-^ 

 many of th:; cut-over ar.oas support a large population of Be ochey ground 

 squirrels ( Citellus beech ;yi beecheyi ),- The statement, is ' of t'm made 

 that this species is' extending its rang.; to hi ;h.}r elevations. In the 

 Stanislaus National For.est, Calif,, th.js :■ •squirr.:ls did increase on 

 cut-over area-s, either' by migration to a habitat made suitable for oc- 

 •cu.pancy by th..; cutting, or by th.i br.j -ding of relict populations. In 

 •either event, .the result v/as a noticeable increase in this highly adapt- 

 able rodent* Bocausj thj Boochjy ground squirrel is food for certain 

 predators, its increase taay b; follo^.'/ed b'; onlargomint of the population 

 of th. carnivores, .'specially rfhon othgr habitat factors are favorable. 



-2- 



