13. 



ISffft^et of yr»fedg on Moietur». Bx|.«rifs®3nt»r8 «4r« 



agr»«»d that on* of th« injurioufc «ff«!ct« of r«»cie on crops 

 ie th« robbery of soil moistur®, ffej^r^oa stttt^c 

 (PhyBic«i Prop«rti«8 of Soiis^ ig.5) th««t w«»«diit JAr-* tno«t 

 injurious in » dry ollmat*. It l« further e®«^2"'--i'iy 

 auppossd th«it w&sds r»iiulr® i3or« coxstur© foi:' the ?rodu<stioa 

 of a giv«fn *^i«mat of dry matter th«a <3o most sgrioul turai 

 piant»» nay« an4 Smith (saaa, 58, 888) in rafsrring to 

 pigeon grass (shich wae uai«d in t»;i «xp»3rim*nt to d^termin® 

 th'^ir »ff#ct on oor-n) »*#©» to voice th» gfin«rsi bsliaf 

 as to all w««a» by statins* t^J^^ it i» f-'it* |>rob*bi« th&t 

 th9»e w«6<2s ue« mor© water in producing «s pound ©f dry 

 matter than doss corn* 



Tht ^innftsota Station (>lnn. ^8, 586) in thf* 

 «xp»rira«nt just rsif#rr^4 to ^AX«o sec. p» ^) founS that th® 

 moieturs in the corn plat "^'n^x^*^ no w<?^© £r*rw v6ri*cl fro® 

 36 to 20 per C4»nt C<Jata approBim^tect from ^ratpbic t«»bxe) 

 «fhii« wh<»r» w*eils wi»r« growing in tb^* corn tb# variation 

 was from 4%J,5 to '? 1^ a difference between the ainiraua of 

 13 % against w?i^7vw©«ds gr**??, Th«s«i variations occurred 

 bfttw-^t^n Jun«» 89 i».nd July 2S juet '=tft*jr ths w^a^ds w«re 

 puii*4« On August S tb«f moistur® in th# w©9d-fr©® po-wt 

 r*ach»d 17 %, which w^s ,th«> iow««t of th« evasion. 

 AsBUtting that this was about (^^ loKrvr.', t-'..',; .i.iurs; , .:;^c;. 



