Inoculation of soil with nitrogen-fixing bacteria

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Title:
Inoculation of soil with nitrogen-fixing bacteria
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Book
Creator:
Woods, Albert Fred, 1866-1948
United States -- Bureau of Plant Industry
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U.S. Dept. of Agriculture, Bureau of Plant Industry : ( Washington, D.C. )
G. P. O.
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oclc - 61357178
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U. S. I) E' PA T I E' \T () 1A G R I C \I IAT U RI.
BUREAU ;iF PLANT [Nl.'IRKY L .I.l IN N1, >, PART IV.
B. '1. I \ALL AY, LuX iV "' C i.:1'
)* ^ .. ,......... ..... .......




INOCULATION OF S(.--.






NITROGEN-FIXING B A tm

13Y
in'V

A. F. WOODS,
AcriGxo CHIEF OF THE BUREAU OF PLANT INDUSTRY.


ISSUED MA1Y 5 l).0


SS ' T.,T( LiY


WA \ HINGTON:
(mVERNME KNT I'PRINTIN( OFFICE.
1 )>: .
















B. P. L .-IMi,


INOCULATIO(N OF SOIL WITH NIITR()G(N-
FIXING BACTIKI1A.


INTRODUCTION.

The lmp ligation of the results obtained with pure cuiltiiurei in inoe11-
1'ti'_. Ir.iiiiiiius plants haIms resulted in a very great (deimanId l'ii'.-
ma12de upon thle Department of Ag'riculture for in(oculatin" imatl'e;l].
The distribution llna(de (during 190<4 was for the purp)oe of o)htaining a
large IIUiiuiePr of tests of the mletho(d Iunder averae'o farlim conditions,
aidl it was imllpos)sihle to anticipate the deniandl which ihas arisen this
-pil." (194>5). the total (quantity preparedI for spril- distributionn
haviii_. been p)rollisved earIv in February. It is expected, however,
that this fall and next -iprinr_, a further distrilutio)n will be made a- far
ts ourtit limited facilities will permit. Statements to tlhe et'ect that the
Department lihas topped the distribution of these icul lt ure's are therefore,
IIerroneous. Appli:cations for future distriblutions should 'tate what
,';uIIII" 1is to hie sown. time o \ s'o\ inI-, and quantity of seed to he treated.

THE COMMERCIAL PRODUCTION OF CULTURES.

The patent which the D)parti ient of Agriculture holds uponl tli
method of gIrowii.. and distribluting these orp'au'isl-s was taken out in
such a way that no o,, canil imailitain a Ill a ollool of tihe alllIlfa'ctlll'
of s'cli cultures. It is held in the iiaiie of D)r. (ieorge i'. Moore,
who developed and ipertfected thle mIllethiod. a described in former
pulli'cations. Upol application the l)ela'tIrtlmIt tlflrnihes x1 without
discriminjation all nlecessarv information, and Ias far as pos,'-ihle "-start-
i1.12 "or foundation cullure-s, to the ac('teri i1 ists re-rsiitinu exper-
Illnent stationlls anld commercial collncerlls which c:ilai to lie properly
e(luipoped,. lbt[ it doesil. not in 1vany vay 'j.ii'antee their prodilct. It is
not likely llat per-'on witliont expert kno\xlid,_-., a: s.iicel-'ullv
nmul1tiply c ltures of the-e orgVanisms for sale or distrilmution, and it
is lunde.rstood that any cultulir'e fturnis-lewd lre to he treated accord lilw?
to the ilmethods (;devised Iby the I department .





NITROGEN-FIX-ING BACTERIA.


Before experimenting with anyv bacterial preparations for legumes,
thle farmer should study thoroughly the soil conditions under which
the use of cultures offers any possibility of gain."
Brielly, these conditions may be summed up as follows:
WHEN INOCULATION IS NECESSARY.

Inoculation is necessary-
(1) (On a soil low in organic matter that has not previously borne
legum1inoius crops.
(2) If the legumes previously grown on the samine land were devoid
of nodules, or "' nitrogen knots," -I,,, ing the need for supplyiing the
nodule-fo (3) When the legume to Ibe sown belongs to a species not closely
related to one previously grown on the same soil. For instance, soil
in which red clover forms nodules will often fail to p)ro(duce nodules
on alfalfa when sown within alfalfa for the first time.
WHEN INOCULATION MAY PROVE ADVANTAGEOUS.

Inocuilation may prove al%:lltalgeous-
(1) When the soil produces a sickly growth of legumes, even though
their roots show some nodules.
If the cultures introduced are of the highest virility, their use will
often result in a more vigorous growth.
(2) When a leguminous crop already sown has made a stand, but
gives evidence of f:iliiiu,_, due to the absence of root nodules.
Thie use of the culture liquid as a spray or by mixture with soil and
top-dressing may save the stand if other conditions are favorable.
WHEN INOCULATION IS UNNECESSARY.
On the other hand, iocu/lation 's uncessair amnd o, f tittle pros-
J2cc/ f'/' '- -
(1) Where the legumininous crops usually grown are producing up to
the av( r:, -, and the roots show nodules in normal abundance.
Cu+llt es Of i' *,,,./ 'ii I ofJf, r,'/.rb,', increasing yields under all avr.'i,' conditions. They
do not contain the nitrogen itself, but the bacteria make it possible
for the 1,.:-Ii ,,. to secure nitr<',,w.ii from the air (through the formna-
tion of root nodules), and where the soil is already adequately supplied
with these bacteria it will not usually pay to practice any form of
artificial inoculation.
(2) When the soil is already rich in nitrogen.
It is neither necessary nor profitable to inoculate a soil rich in nitro-
gen when sowing legumes. Not only does the available nitrogen in
a Fully described in Farmers' Bulletin No. 214 of the department of Agriculture,
which will be sent without cost upon application to thle Secretary of Avrii-.-'lture.




r i.ai i:F-..


the soil render thI formI:tiol n of Iodtll'lel I ei Icessa: Iv. Iit fiit '.It. i ,.4u
materialls ill the, soil large l prevent the bact, eria ; 'roii l ,,'I nodule.lt11.
Alv iV merea-ed \irilitv in flil,',ope',,-fixin2 po er Io),) d, ( I,,, ; (,,
tlp ,es f b teia \t 1 '1i.t ,ilytri ted l a,,Il\ be w rapidly lost ill t .- il cmil:tiln-
illf t a n daoe altlitro2._. 1'. be ause the }a te i'aI :1rv r ptl> lY 111111 -
1pi.i',_ in ia eliediiltl ill which there is no premimtllill \oI vioor ill ccllrin-e
1 UitaIl l h.rii- herc 1iitre Lt'Ii.

WHEN FAILURE IS TO BE EXPECTED.
Inoculation will fail xxwhere oll r coidit ios+ll (:lI' ide l'i'In the n1eed ,of
bacterti:) :iar' not tk it tkoin t l lccon l. ats tlh 'o,,llowi,, :
(1) Ill soil t iutt is atlid and ill ,,eed of linr,.
I.il,, i,'_ to corr, ct a 1idit i v i' itii, ) important for l 1, proper aclti il\ i(f
the licteriia its for the o, g x hii 4o 1 th ie pll i,(.
(2') Il so xll that respods il tl arke (I waty to 4t'1liliz/ -, '11hl :1.'
potashl, )l(iopelhori, acVid, or lime.
The activity of the I ehitra it secIi, iiui,, nitrwe, in lfroi tlt. ail-' ard
retnd( I ile'. it av;lilableh to hi e il ,.1_r h ,ii ,d not (tdo awav with the ,)1 tdn
for s (i1h fertilizin- e'lel.ents :as potallh and phospho(4Iiris.
(3) It ilnsl s 111o l) e rel bie berejd tlit 1 ]'t .ll l,',ln !i ,1/ i t,.i "1114 /1'k)
lie,,, eii, xit \vill nII iot ove.1,co me r, sults dtie to bad seed. improper
preparation and ctlliN atiaio of t i',ttlld. and decidedlY adverst(\ e condi-
tions of weather or climate.
In the is of cutlt aes also. faiilure is talmlost certain wh r tl e die'i-
tioln are not atrtl'null+v stulldied ;Inll ilte1lli'el'v follow d.
(4) A 's the lph s. A ic'-, the che 1mnistr v, aIdmI tlhe Iio(hl. o.v "f Soii S aire
stiudid iie il the i ;la orltor\ and (i 1 1114 le.11Sn of actual I ielt d-plot tri:Ilst to
dleterl4ne yiehid and qulitii .v of c',opsl and the 11,eldct of oile crop on tihe
followii,,, cropt ,, thle ery _.*',..,i .omplhxity of Soil and farlll mana e-
llent1 l b1 eco eelll( ll l' lli ife-t.
The vallu+ of pure-bred bacteria. whether 1,-ociated with the crop
orF xistl._' ildepet dent le\ i x th(e s (oil, : ls is true' of fert'( ilizelr.s call not
e predicted with certaint'ol( an soiit, et il ihout tr ial. Sl. ccess. on simi-
lar near-b, l ,,la-ds ,a:1v lhe taken as 4,ood e\id, e. lut, tunlike fer-
tilizers, bacteria s-houhld ill time 1we so iex!pe,, ie tha:t 11e ,h {':l ,nielr
call afford to tr, ttev t!,i, for e:1,1h I. _.ni ntliuiioll crop on ea:c.h I li t'd m. soil
type o),, hi, l 'll. The methods of distribulnllint, ill dried form11 ancd the
va-,y imethhod, of m multiply i,_2- oi ,l th, a ll 1r11 il lillicient qua, l titiie, lo
intoculate fields will Illake it possible to {uave ill tihlds inoculated :It all
times.+
COST OF CULTURES.
Til,0 question of the proper price for tlie com, et-rcial product is caus-
.r,' considlerable inquiry + v a -ill'ii'. prospective experllillenters and is of
importance. The expel nsew which at comlillercial concern llnust ilece's-
sarily meet, such a-s rent, heiat. liglit, iisuIlraitce, po', i..* advertising ,,,_





NITROGEN-FIX I N( BACTERIA.


etc., aside from laboratory assistance and clerical hire, make any com-
parison with the cost to the Governmient of similar cultures difficult.
The statement that the cultures cost but a few cents an acre refers
only to the raw materials which make up the pack.-tg. It is more than
probable that natural competition will considerably reduce the present
valuation of the commercial product, and the wisdom of patenting
the Department's methods to prevent the formation of a monopoly is
already demonstrated.

INCREASING CULTURES.

We are receiving numerous requests front persons who have secured
commercial cultures, as well as those sent out from the Department of
Agriculture, for information as to the methods employed in prod w,.i hg
a large quantity of liquid culture from the dry culture secured as a
starter; that is, how to make an "acre culture" do for 25 or 100
acres. Such methods will give good results only when special pre-
cautions are taken, and on this account have not been generally reconm-
mended. The contaminations, such as yeasts, molds, etc., which are
bound to occur to a greater or less extent, are apt to take possession
of the culture solution in which the bacteria are being multiplied, and
unless great care is taken in thoroughly sterilizing all utensils em-
ployed the resulting culture will have no beneficial .iL.i t. The extra
time required to secure sufficient r<\ th of bacteria in 10 gallons of
solution from a dry culture originally intended to produce a 1-gAll'il
liquid culture makes the risk from contaminationi much greater than
where the dry culture is proportionedl in size to the larger amount of
solution. If a growth sufficient to cloud thle solution takes place
within two days, the chances of securing an efficient culture are much
better than where a longer time is taken; so that the volume of solution
prepared should never exceed the actual requirements of the occasion.
The following directions are based on mil,,1ing 10 gallons of liquid
culture, sufficient to inoculate 20 bushels of seed. By a little compu-
tation tlhe directions may be adapted to 5 gallons or to any intermedi-
ate quantities.
PREPARING AND USING THE CULTURE SOLUTION.

To prepare the culture solution, first select the tub. bucket, or other
vessel in which you wish to grow the bacteria. Cle(In ,etld cald it out
//,lur',,/,ly. For making the culture solution, rain water that has
been thorol,-iJly boiled and allowed to cool is best, th,,u']il any good
drinking water will answer. Add to 10 gallons of water 12 ounces of
either brown or granulated (preferably granulated) ,iig-r, 1 ounces
of po)tassi um1) phosphliate (monobasic), which can be obtained at any
d ri', store, and one-sixteenth oulince (30 r: In s) of magnesium sulphate.







Stir until dis ,l, ved, f t' t'1 Lt, t te t l thhtnllIv 4'i the :ll ) i. ,e -l ulltilli .l-
the lbacteriat-ladt li c to t il ad l d p ti he cot\to iin Ito the ltio 1ou
l l(i. handle h t'v lhitl' tlli a i \ all'soluttel. v "l hiejesary. C'o er" t ei ti(ll
with l (it.h1all .loth to l ot tl trom 1ust, nl dhl spowe'S. th.. Kee l.p
il :i wa.rill plate, I'll it ne\c r let thet tet pil ra t 11tUre ri-,se I (o b lodI 1 eato t,.
Aftcl, lwenltv \'-l'o tr hours ad wi o ces o;f aill 111(mitilm plho-plhtt :11ind
aI Willow tih ilixture to italld Il'r til e the tit w tvII -fI r oiti stll. Tlhe li lid
should liow It'e vl ttt l readl v for It; ie' ,sthiilt iii'it'i i i iw I l i i tt
taktn pilllac'e tI tli i il, a out l1 ii, cloldiness. L ihrtli.er til e -htouldt[t i,
,-,'i k re. riot to excel a le'w dah s.
T i'ii irn l ,etr. l tifL. i' o V 'i i lt'd cul i ir I(ii i to I ltll i tI t I I, e
thoroui 'hltv aboI Iut oiicdat, l-:lt of at 4',llon I pe shtI tlI Wl. T]h)lis iItnocW lahtit*H(
mItat l dit etillite it I er i l r fil te 'et1'ir or ) tIIY s ri kliu ticltl I le (I('i t
liquid ol tile st t S i I ot )1 a c la lIt looirt and setirril'l and tltl' i1im1+ tdie hl. i ta s
of t'seed wit lielet 'lilst h uttil atll a' thor'IiohlY lois4teied. Aiftiii ilo -
I tlation (ftle se di, sIiu. ld bl e spread tl out ill :a leall. ltd vt tha t tla e 'til
s l i enlti d tlen ity to handle. If plant iiIn is noll t t (hi-e do IIti o(Ice(, tIl-e
s tled tInI( I t'I i i'o, l t o nth ie the prevent moldiio,.- I (liry weather,
liabout 2.') bushilils can ie dr 'ied ill ho rlf' a d liv o(I illo sqt ae ilel eti of l oir
space. To do t1ii thete Illsfc |e speeval opnwildows (r door's lo
altlw a f'ie circiiiilion of al'ir, iand tIle s leed wliiIt e f irequent lIY stir'ld
within a lawn radke. T1le inoviultated seed, if thorou"'illy dritd. 11:1Y
lsatillv ie it kept without dtteitor atl ion i for seve tral i llionths.
t i>L,- hie t ,.sl/. lTake eI'loioh dry eartllh tor sallid so) tihat t(e soitt-
tion will moerel lmisteiOn it. Thle sroiel biold ie preferably frm tli' it
field to lbe illoitlatedt so. als-; to avoid spreading diseases o" weeds.
Mi\ tho ,li'-'dilY, so that aill thle particles of so)il nae, o l iiste d.
Tholirou" ilv i lix tlhis earth within fouir or live tine a li ,0 ; spread
this illoculatetd so, il thinl-yI and evenly over t ile prepared t'trtlld
Tx Cutly as if sp' id '_ fertilizer. 'i e ll i hoculated o"" il shi uld bei t lilar-
rowed ill inilliediatelt, eto protect te eit a bacteria froi li' ',l'.. Ill us.ii.-
tlis i thll eiod aitllow 1 ,:.il liitot of tie n liquid cul'tu sutre to 4 aces> m s.
l.ithu er 4I tl e telthods described illay bel t ise as lit laty be mot'st
convllenient.
T7 1 ,,vi i'<'/ i! | 'y IDT+l!!, /1,,i <'".s ii p )I,' i, il'l.y .le, iiwit 1,, ?,
i,,'il, /,f, l /i, l, ,,i,,ii, If thle local -i'11'_',_ is d es not hiave tbeil ill stock ,i
lit, cal doubtless secure tl'henl within It rteasoiinabt~le timlie.

KEEPING CUJLTURBES FOR FUTURE USE.

Tli'l questions is I'l[ it.,i tl0V airisili,, as to tlihe possilbilit y of thle fairll-
er'sl" I'.,, ill,'j o-)ver cultullres front, Otte year to atnot ei" l y ',,, i,.- a
little of thit liquid vullt ur i lcottoll and dr.yiii-< this cottoii. Tlt'i^ rs -
1,ni++ ,]t ,#'++i7r s in'r / o i t /,, 1n a place so readil w. ;it/'i o cl;dpread soi| ra"iiidl, that kow a 'su d


KIKI+KI'IN ( A'L' TIV l<, I, K V l I'T I t U t: I ,! SlV,1.





NIT'ROGEN-FIXI NG BACTERIA.


,ii,,. results it is absolutely necessary to start with a pure culture.
The pure culture, moreover, can only be prepared by a trained bac-
teriologist with laboratory facilities. These cultures in the dry state
will keep), under ordinary conditions, from six months to a year.
There is an additional reason, fully as important, which makes the
above method impracticable. The cultivation of the bacteria for any _
considerable length of time in solutions containing ammonium salts
rapidly lessens their infective power and their ability to gather nitro-
gen from the air, so that transfers or new cultures made with absorb-
ent cotton from the cultures prepared for field use would contain
01 g.iii-i,,s of reduced efficiency. It is partly owing to these factors
that it is impracticable to distribute the bacteria in liquid cultures and
maintain the requisite effectiveness.
In the use of cultures for inocuilM:,ti g oil the farmer should be
guided, ais in all other matters pertaining to soil treatment, by his own
peculiar needs and should not give too great weight to the experiences
of others whose soil conditions may differ widely. PI ,'oid he ,rh n,;h
to 'finxi' 1argely l/n any niIr tIn tiel fori /<'i' (atj yr pwt/1
'wl i/u c ,,'i hactc'mi i/a o aniq ,,/,,,i r atf/a'r., ,,;/,,ioai ]re.iof'm si/ n.' ,l-
bntru1 elil hagi It a snl/I ra!'
lnm'"/nl ;'n a sml/ll vyl.
DANGER OF INOCULATION BY SOIL TRANSFER.
Satisfactory inoculations have been obtained by transferring soil
front old fields on which thie legume has been grown, but experience
has shown that there are da ,.,'r incident to such methods of soil
transfer which it is wise to avoid.
The source of supply of such soil should be very definitely known,
and in no case should soil be used from fields which have previously
borne any crops affected with a fuligi'n, disease, a bacterial di-r,.',
or with nematodes. Where a rotation of crops is practiced, it is often
difficult to make sure of this factor, so that the method of soil transfer
is, under average circunlistances, open to suspicion, if not to positive
objection. Numerous animal and plant parasites live in the soil for
years, and are already established in so many localities that it is mani-
festiv unwise to ship soil indiscriminately from one1 portion of the
country to another.
The Imacterial diseases of the tomato, potato, and c:m'l. II l. and the
club-root, brown-rot, and wilt disease of thlie cabbage, all inmore or less
widely distributed, are readily transmitted in the soil- while in the l
South and West there a:re the wilt diseases of cotton, melons, sweet
potatoes, cowpeas. and Ilax. and various neimatoid and root-rot diseases
which iiglit easily become a serious menace over areas much Ir..r
than they now o'cc'upy if (elii erately spread by thie careless use of
soil for inoculation purposes. There are several insect and f' i g'i,-
diseases of clover to be avoi(lded(l, and various d(liseases of bIeans and
peas. Th'l're is also a disease of 'ilfalfa:t, le leaff spot." which is







<'i -i^ i.ii~'''ill sonic regions. Tlwse arc ('11 ,v at fewt (of man di.--
cssliable to he t'ranlsimittedl ill .oils. The farmIer shouldl therefore
be oil hIis Iliiard. The dan',-.er fromi uch usoirce s i- l) nv ]me
i n IllI*. ,T Due'pia me t' DO i( t1'll ()fii I rici t *lt( r te h sli id ecitfli Ia e- u i 'l
Such accidental diil rihutiml reported, and it tit(a hu~ a m (d"e. ol i lllt)
soil for iriouitIi tion is rinIdh tIo flourish l)Y ftarmet purcit't e witho i t







lO question "llfalfa e Joil."- cm..pea soui, etc., there is ) vr rie atso too
believeI that experience will d(temtoltenstrte ta th t f)lly of tli, hIIlI i t [ :itZI d

I)Of swarc ldv t i ill) l itall'tc is ale a1r:1tl f oi'.e iiu iiitiatii-' noxiou-s
weeds and ise a a.scc t l) l on dl u tli- [)lan! loie ino ulaitio h I wialt (ii-f
.SOi lii. tve all 1 ,- I weed" ]inii v o I a l en it haurl s ile Iuthl tirf t ldtn d.
thie ,.l,..t I I l)e f dt b er ( li (''t seeds requirit" but a1 sliu -ht ,i111 _i i ie
SiIt l.lr.iilid tH- o i)'rodlle -'ctmtirx at ion a ure al wats' it ra Ierace. The en r-
IIIm IS I ti'l't ti o cto'tu l callsedt l 1).v ini r'tdutcnd i ltn :Itls a d e -s lx iould
c 'OM ,\+ a1 W:1a,1i1i,_. Aldt lead to caution. It i- ]1()( the paIrt oitf t,4)1,)
jidl..''iici t to view tit, risk 1ai a sli iht o alle stila, d uy t ll Ie ('1d i 6ii\u.
PURE-CULTURE INOCULATION.
The extensive experimlent's carrit'd ot b ,\ tlhe Department oft. A rri-
iiultiluii'i d riiit Lit li dem' i st i' tedt the flat) l that, I )v tilt, pro'qe r Il se 4f
)pure cu'ltures-.n (hli l o le h:1t106:1 a :ae 'tit:ally Vcai l ied ia n to tli -. il ill
suli h \a Iav ais to foN i o)ot od1i esi. and \01h(,0' 1 tthe1 r coin" ditios2 are1
f l 'lioa' 1le l tI itoiU'tlt ion thtli> l' u 1 .u'ht a ouihi i Itit imake- i ml-t ilul tliel
rx wth il f leac i l i'_u i' ilt >oils we h erel' it ,ad4 previiuui,. fitail'd fr(ml
tltI lailck of lac'teli u. The o xiiial ii ltu e-, sed hoiwn utever.l must bit
tprepareId with tilt ta'e IIIat l. t tit l with at viPew to prli, rvii u andl
inlcrea-iil'_. their natt-al po etr ast ".. t o-e_ tixe"l rather than 1erelV
to mkte themI -'row utnde ltarvoalt' conditios. Tlle mlethod-i del\ i-ed
ill otir Ll+ o (4 14:1,1 I'llul- lh siolh_., a e ased ( well-recoili/,ed
principles 44 plant lv'edii,,-' a1d -selectiot. :11)d mark ; I de i d odtaida ce
i l thle p)oIdtction oitl cultures I'mo >oil iot t ionl. The old pllurt-
cult e ethol.d \ were Ito )I ll'effective, fo )t" lreason( I Is c ilea-l+ s Dr. oolre il Bulleth i No). 71 oft, thte Bureau, oftt Pktlant1t l11d lt. rv and
by Ill. M ton, and Mr. N'obhiwi-t. in Farmers' lll,-iii No. -214.
T'lie I llepalrI meillit' of \"ricill t ire is cont 11111i I(lit, work oft develo)p-
I lt, l,[: lt lt +' f v t lt t t < t, l t l ti t+.. `U 111 \\+ fl + \\' h '\tl ) -
i ii_ tVI tt l the bacteria a ( to. .iated \\with I'tti iiit, t plat+ -, \ hich

n w,,ill have ,, ,i +t I 'tcr c ivit co,,lec lin + 'l lhoi t tl"e ai l r mo e itro'eii,', per~
HleI th1 an1 forllI r,\ t cl i V ,C( (II in I I tt l f )l+ I It1vaila Ilel 0 I' ( l ,lo ato it ie-.

It is de.irabl ec I thlatt simI il i:v1 r io]vcnti. Itit )II lI l )IId I w l cmn1'( w l t itillI
Irefer, nl+ e It to It e i) I I I _., ,-'i.I i II .. b ta c t ir a cxi l ItIL it- t1l e -1 'il imi ( I w Il+d -
ontit ('d the 1' I. 1'", ". l q l] I : 1l e-ttp-l ha v ,e itI ',:lv hieeo1 |;ie al,,._'
qt, i- line, lI u( ie vrv la 1w. deIand ill wc lture- fom l'm.ii .in ,ti- p,-4.
I bv co l-timill,.t t ih e of (hr l >rallli, (4 fore , ha -seriottl\v et' 'ded
tlie-e' iniv,-ti_ ,ti l,. durin,:,(the p1)-t yeM:i .


lI'K I E -CI' IT, I' It E I N( to, A I 1)N.





NFI RO EN-FIXIN( BA('TERIA.


The Department is ready to cooperate with experiment stations and
commercial firms, to give and to receive -ii ,:gestions, to test the prod-
uct of others, and to furnish, as far as possible, cultures to be tested
in thlie laboratory and under field conditions.
There is nothing in the nature of the processes involved which
would prevent a competent bacteriologist, after some experience in
this particular field, from pr.,,1cig cultures of as high a grade as
those sent out by the I)epartment. and every assistance will he given
to competent persons desiring to undertake the work.
A. F. WOODS,
Act;I(/ q,", Bureau of Plant Idu try.
Approved:
JAMES WILSON,
<'/I(rt/ f A/ gncull/ are.

WASHINGTON, D. C., .May G, 1905.







UNIVERSITY OF FLORIDA

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