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(..r. :.}~ Allen Whi take. ~ 'r.t ~., •, i '. :- .•,.. ,
<br />!,... gip' ` „r'
<br />~-~.Z,?..:? ,f+Y+~• ,'`, ., 'J'^'j .,•p. •'tl' .. '~.. '•(.e'..Y,~1i~s•.,Ii~~•~'~1 ,. ':.7(•}~i+~~ T
<br />•j,; • r 07 December 1981 `, ., s ,~ ,
<br />' , :,Page 4 h1,~~~'p"l~~y
<br />t.}~~+{•':r~.~!~~'~~)J~i~yrl,.r,., rti'~ \ + '`i.:' ~.. ,1,; 45 +, j , _ ~+, } , L~}.,!X\~fk,d5 ~.
<br />:'+n', u~ ,. ..,.. ~ .. Mfr/1'
<br />{ h`'~ r!,t ~f t Q`:
<br />114`" ~.'f~r :. ;.. , . ~ ,~ .. .. ..,.: .. :. a :r.,i ~:;~.
<br />r " f~?+•~ w},q,` :'•j~{'h':;!'`.and as , a consequence;',grazing pressure ion; the study `~iK :+',,b~'=~F ~''
<br />~` ,~yy yC`u`~1}:.Y~i;/. ~:~Yl .^, ~ .~r .y c.Y.~`a1 ~$.. ~hiv ;~.:.
<br />n~M1 r°.r`:'>, ^',.'-.i•4' .,:,., :'.,,:;area was severe. ,-;Ittwas obvious' to~ us~ making the ~ • ' i•? ~'~,,--~~-. "t
<br />~ ~Yit?.1 ~FI,; :^y a..r., r.
<br />:C,mr.t:~,;r;~::•,,,1t'-F=r'.,, Y.'measurements that 'livestock grazing of the forbs and~~.%~+, ;: '.-r~)>f/y~~,,;rr~,
<br />'~;Fx;~;;'r.•r+~=-~:!..i' `. '.,:grasses was considerable. A portion of this increase -• '• .+" i,pj~' :;,
<br />~cV,P."trS~h:S.:•.::~'_ r,.k~1];;: '.•.'' .t4}: y'.,~~°.r5''A1~3>.;,K' ,,.
<br />•~'' '"~' ~- •:r~ ~, in grazing was attributed to enhanced palatability of •' •• e>.~`~d... '':.
<br />;.t +T: ~:• ~•• ' ':: t ~ .' `•'' forbs and raises due to the nitro en fertilizer. ``Add a i~,~ ~t~v,',,
<br />~;~..: ` ~ to this the fact that on the study area many of the ` ~-" ':,.~,f„ -ti;
<br />~,~.{ °~'"~: `.; .. forbs and grasses had•already grown, matured, and dried ,": ~'.~!~:~~y`'~V,`tt~~~i~i
<br />~ "~:.w . ,,.r ... .
<br />;, ,;-:•;.;,•.;;,,,', ., ,, •, ':.r.:::.. at the time of .measurement (August) while at, this same .,„ ~.,,1 ~~.y~;•,11
<br />` fr'
<br />''~:?'"('~'`.':'~';" ~ S:~': ;' •"time sagebrush and other shrubs were reaching their peak`"'n4'~ iy ;,', ,;s.P
<br />._~,~,.{ti~~_'rj~,,,S',F.''4t,;,'., 1 ,, ,,,.,productivity it is not surprising that relative yields. ;y;yy_,p~;,%at tj,~'.'`y:~~•
<br />of forbs and grasses decreased. ~• '`~'":~r~',,*~9 "' +'
<br />'#r"r' 4r rp, , ! ~ ;.~:. ~ ' ' ~::t..+.~.vr.;;,:;#ro•iJ;'`y. 5,(.~, 1, ._'~:
<br />+oL~~.~r• if ltrl nS a +' ` t ~. 1,, 'i'•. .~. .. r~Sh
<br />~''•'•• -'~' ' •" ~-••'~~ -~ ~ ~ ~' Based on these results and other experiences the ~~.~' '~.gr;,ci.V'^,•..,,!
<br />5.11'~<«~~~,.';!j~,.,;'~'isiy(,';';'~'``'~;j';ji••: Colorado DOW has always taken the position that livestock' _ '';;r,y?±;~`
<br />' .~lt_ a,~r.~,.
<br />''''' '• ~': ':. grazing must be controlled for at least the first year -'. .T."' +
<br />~`Y':~'' t ~' after fertilizer treatment. There is a bi difference in `-.2if.i:Y+?' ~;~"~'
<br />:_~(t,S,},.t:,,,.},,1.,,r,;.;~A,t; i', : ;,' type of experiment to be conducted and measurement proce-,.,,,,;', ~ 9~.,
<br />•..., dures to be used if the question was one of ecological ~^-•-
<br />'}~'z:~;~,~;:'.'asakl!i;:';+",:~d;~;h.;.,•.' ':impact versus that of mana ement im lications of an =..''1•"J ~ii~=•
<br />,•."G^'':o i~';.•1;'~.•<<e;:. ~ : application of fertilizer. On page 17 the author raises "„'.,fiTf-';,..~
<br />1AL}~, 1. .,
<br />:.' ~:1,;-++~'";"•,'';:.•,-•. ':%+'the issue of decreased >elds of ve etation~on control %:••
<br />A.~, .fly, ~.::•~: ~A Y, g •Ip (L'IJ; "i,.
<br />'; yic i": „~~'•' -`.,'~• •; :;'i ,'plots as compared to treated plots. It appears that this ~_, r.w,Ye;'~,~{~,,:;,.,
<br />,~:~;::!~'•'~r' -• y`.'response' is due to a large build-up of litter that has ~ t''•'•'"~'':~;~.~;•~`+:~:'
<br />„ occurred as a resul[,;of, total protection from grazing. '' `~=`+-';;:y;:r
<br />Jv,;'.. ,; . .
<br />:~;y::~m~•~• ;::fir.: .It has been shown in several studies that litter build-up ~~ ~:~!;~. ;'.
<br />.<~.,';;; ''without removal will result in a decrease in herbage yield.` -::~i.'r;!',, ~:
<br />>~'1' ,' !'- ~. The litter build-up from forbs and grasses was considerably ^
<br />• [~,. ~'~~ '~ greater on treated plots' than on controls. Again, the .: ''.:;;;.;~s',t•;~~
<br />'.,,~,~. ,, t , involvement of grazing is important and must be considered e-~'i';~~,'f~,y~~i,,;,na,'
<br />,;h,;,.~--~,%:,,.,'; ~.,+:.,~:`;~before.forecasts of. ecological disaster are made.Also, I ~~~~" NFi~•dyt'
<br />:.i:,-.'-tai i~Yi~~r'.1: ... .•.r;•,~ . .::. .::.. ..... .~~i~, r~•~y;
<br />~~:..would challenge the author or anyone else to inspect the 3 ti.:, ~.•.•.
<br />' ^r;.~^ stud areas in Middle Park that were treated and rotected :'t,";,;,~:„(~4,
<br />Z: 1!?~,,,; :,1.•.. ,for l0iyears and honestly make the charge that there has .;`.:j~'N'-;rA~<;~.•
<br />t}~!'!'. ', been a serious deterioration in range condition or that r•,';,f+r~ •~'•~~+~
<br />, c _,,.X•~..,a
<br />~~?,•,;' , •' .the health of the sagebrush ecosystem is in danger. ;,;r~y~.;•,,:..
<br />~~=!~`~•. Page 18. We fail to see the pertinence of the allelopathic dis- ~ ''' •
<br />~;:,-
<br />;•,~~: .,,., ~,,..~.,,,,. cussion to nitrogen fertilizer. It appears to us that
<br />':;,.'.. - the author is attempting to take as many unrelated.eco-.:` :`;`',.:.t;,~~-;;.
<br />. '' logical observations on sagebrush communities as he could ...,' ~:`"'+}`?,~; . _
<br />' find and P ~. •;!`4;" f• r. ,
<br />put them to ,ether in the context of fertilizer ~.[~^.'"' '•
<br />impacts. This is not only misleading but highly unpro- .~•.;/~~ ~y;; +;
<br />` ~ ~ fessional and unscientific. One must only draw cause and ~~~';'>'•`"f":''"'
<br />effect conclusions on a specific subject from experiments ~' ;;h,~,~~h~jF]? . ,
<br />that are designed for that purpose.
<br />4„ ,..• :. ,:... In summar the ~,:y:,,,.;!, ,
<br />,, .. y, professional literature and our "r:•
<br />' ~ own research experience in no way support the author's
<br />,'
<br />_ d~,•,:~.;,•~ contention that application of nitrogen fertilizer in a
<br />• •. .. sagebrush ecosystem will result in a monoculture of
<br />' ~.' mature sagebrush devoid of reproduction and desirable •'. •:~ ;T^i`;~?':~~f ~ ''°~
<br />herbaceous understory. 1"•~
<br />. <` ,
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