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memex/0_inbox/books/PDM/Bill Mollison - Permaculture A Designer's Manual text/090.txt

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Leaking down on a bare winier-declduuus bee, we
see a lypiral iraelal, whrch we can also lind in lhe
nilguriles isarid hised by lighrningl in sand dunes, and
in lhe sharier zones ol explosions Tree roots are, in
laei, a slow shaller nr explosion underground One
way Io planl an apple iree in very hard gruund is lo
delonale a small plug al gelignne a Yum or lwo belaw
ihe surlace. lhe rooms will vallow ihe shaner palum,
aml iunher elabomie ii.
Seallers Mubptds may ar hisl seem lei presenl a class
el events unrelaled lo eilher flow mudelr or Innshli,
bui iracrals are being used l0 describe lhe scaners bl
lree elumps in grassland, ar lichen on a sione in a
sense, lhe surlace al spheroids crealed by branched
phenomena (like lhe plan view 01 a lree rruwnl may
shuw sueh apparenily randnm seallers as grawrh
poinis, or a curved seeuoii shrough the cur or pnaned
braiselus below lhe eiuwn ova nee wuuld also appear
lo be a searier bl puinis (Figure mm These can be
measured by iraeialanalysis.
Fracial lheory may grve us a way lo measure,
cumpuie, and design lor branched or seariered
phenomena. bur we also need is undersiaird lhe
physieal advanrages 9! developing ever rmrller
canduils, Vngrl mall gives many insighrs inio ihis
process and iis ellecis, Large sond are ol use ln
mass lranspnri, bur barh the larninar llow paliems
wiihin ihem and ihe laer lhai lhey havea small surlare
area relalile m ihcir volume makes iheur inellicienl lor
lhe ail/baron or maierials or lhe eondueiion o! heal
aeruss iheir walls.
Ever smaller rondulis have diileieni quail-res new is
slow, alml lviseous in very small illbes or branches,
direeliua changes in small branches are iherelure
possible wilhoul ineurnirg iurlrulenee or energy losses
Walls can be permeable, and ellleieni culleeiirrn,
erehange, and lransler is eliecled (whdherci inalenals
or physleal prsperlies such as heal and lighrl Many
small epnduiis ellicienrly inlerpenelraie ihe exchange
media
Wherever ihere is a need (a calleel or dislribule
maieeals, or Io irade boih ways wiih media, branching
is an eneeliye response in design. lheieirrre, we need
in use “mnny palhi“ in sueh siluahons as home
gardens, where we are always lradlng nulricnu as our
main aelivlly There is lime advaniage in lorrning ihese
palhs as slraighl lines (spud is nor al lhe emense), but
ralher in develop g a sel ul rill .1. ms or
heyhuleshaped beds llhis is also lhe shape oi sacs in
lungs) Cunyulured palhs rn gardens have lhe same
eueei They eilher bring lhe gardener 1MB belier
conrael wiih lhe garden, enabling colleelron and
seryiring lo oecu r eieaie bener muiual exellange
belweeir lhe spedes in lhe garden.
The high-pressure/low-lluw naiure oi minor
branches demands a very large luial eiosssecrional
area bl ihese in relaliuir Io lhe main supply arreries.
Such small eanduils may develop areas wruch m sum
are 300-le limes ihal ul lhe supply arrery iour main
nrads are lherellrre much less in area illan ihe laai
vn
lrachs rhar lead oii ihemi As an applied siralegy,
muliiple small pallis enhanee aur aeeess lo loud
sysielns, or in rm any syslem where we bmh lake and
give maienals
ln mgmlsms, lhe muluple braruhes give ihe being a
chanee lo recover llvm iniury preserve inlurrnalion,
and permir iegrowih in lhe evenl ol minor damage ii
is a louleprboi sysiern oi inlerehange. Anoiher way to
elled iniemhange is in elaboraie on lhe walls al larger
enndulls by involuliuns, allached lins, irregular
suriaees, or re ereaie spirals in fluids or gases by
bending or s iralling lhe eenduils rhemselyes, and in
general inducing a larger surlaer oi roniaei behveen
ihe ulalerial branspoiled and the media wiih which we
wish in udmlge nuirieiris, heal, or gases.
branchrrig in lrees is as onen a mu“ oi errlernal
larees lwind and sail pruning, secaceurs, or "used
allaeki as il is a resull of mlernal cell panel-re; n is as
much lomed upon Lhings as ii is lhe ~besl lhing he do:
We musr lhereiure see lhe branched term as an
inleraelian beiween an organism or process, lhe
purpose ll serves, and ihe exlernal (Wm ul lhe media
in which lhe organism is immersed (lhe lone: aeling
on re exlmally io delorrn rhe perieel panernl
Mung lhe slreainlines islesa el our model figuu
Ln, iluids and gases may pass in eunduiis ar along
'lraumlsslon colds", [nod and srgnals are relayed lo
eells, and gases exchanged. Organs served by or
serving ihese syslems are hallsmodels 0! our iree
lhidireys, lungs» or branching lradals lmesenrerresl
No mailer how long or rompkx conduiis are, in die
end lhelr eonienis diverge, eseape, and disperse, and ac
llie iniahe malerials are galllered Emm dlspersed
saurees li is ilus galhe g and dispersal hum bolh
FIGURE 4.2:
NW1“!!! raerialised lur dilluslbn ul inlusibn llunirs, llmn-yx,
muthms. palm has) ii usualysvhlrnla blallmlnvr and was»:
a hall-mane in an. madluin lhe alvihli oi lhe lunux hinhei
tar-ml: ihe mm: an: en a mud-elem semen