U.S.S.R., 1931, No. 5, 5—68).—Analyses of profiles in the semi-desert grey zone are recorded.
Ch. Ab s. (p) S tr u c t u r a l s e ro z e m s (grey so ils) of T u rk e s ta n . I. P. Ge r a s im o v (Trans. Dokuchaiev Soil Inst.
U.S.S.R., 1931, No. 5, 77— 104).—Analytical d ata are
recorded. Ch. Ab s. (p)
S o ils of th e C rim e a n s ta te fo r e s t s a n c tu a ry re s e rv a tio n a n d a d jo in in g n e ig h b o u rh o o d . I. N.
An t ip o v- Ka r a t a e v and L. I. Pr a so l o v (Trans.
Dokuchaiev Soil Inst. U.S.S.R., 1932, No.7,280 pp.).—
Analyses are recorded of these brown forest soils and some rendzina in various stages of podsolisation.
Ch. A b s. (p) S o il scien ce a s a fa c to r in m o d e rn fo re s try p ra c tic e . J . O’Do n n e l l (Austral. Forestry, 1936, 1, 61—66).—A general discussion. A. G. P.
P o d s o lis a tio n in F in la n d . A . Sa l m in e n (Suo- men Kem., 1938,11, A, 33—37).—The leaching of the sol. constituents of the surface soil and their re
deposition a t a greater depth (podsolisation) is only the secondary cause of the variation of th e chemical composition of the soil with depth. Tho prim ary cause is the mechanical stratification of th e soil constituents according to particle size, the fineness increasing with depth. The subsoil is thus enriched with the more friable minerals. M. H. M. A.
S o il m o is tu r e in re la tio n to m o is tu r e in th e su rfa c e la y e rs of th e a tm o s p h e re d u r in g th e c le a r se a so n . M. S. Ka t t i (J. Univ. Bombay, 1937, 6,
P a rt II , 3—8; cf. B., 1935, 777).— Observations made over certain Indian soils show th a t during the hot period of the day th e atm . H 20 content is max. near th e ground and decreases w ith height; during the cool period of the day the conditions are reversed.
The variation of H 20-vapour content is of th e order of 25% per 10 ft. in each case. The R .H . in both cases is min. near the ground, increasing with height.
The changes are related to the H 20 content of the soil, which is min. a t the hot period and max. a t the cool period. The diurnal variation of H 20 content of a no. of soils varied in approx. parallelism with their H 20-holding capacities, heats of wetting, and efficien
cies as desiccating agents. A. J . E. W.
E ffect of s o il-m o is tu re c h a ra c te ris tic s on ir r ig a tio n r e q u ir e m e n ts . N. E . Ed l e f s e n (Agric.
Eng., 1937, 18, 247— 250).—Relations between the moisture equiv. and perm anent wilting point of soils and the effects of irrigation on th e H 20 content are
examined. A. G. P.
P h y sio lo g y of th e c r itic a l p e rio d of la c k of w a te r in so il. F. D. Sk a s k i n (Compt. rend. Acad.
Sci. U.R.S.S., 1938, 18, 303—306).—Oats are most sensitive to H 20 deficiency a t th e stage immediately preceding the formation of reproductive organs.
During drought C assimilation by plants is m arkedly reduced, and although recovery follows watering plants frequently fail to regain normal assimilation rates if drought occurs during the critically sensitive period. Such conditions lead to deficiency of carbo
hydrate and, as a consequence, of protein synthesis in th e plants, these th en failing to produce the normal proportion of flowering parts and grain. A. G. P.
A d s o rp tio n o n B ra z ilia n s o ils. E . Ma r c o n d e s d eMello(Rev. Soc. Brasil. Quim., 1937, 6 ,7 0 —80).—
The am ount of exchangeable bases in tropical soils from P arana and Sta. Catharina, relative to the saturation val., has been determined by K appen’s method. The low relative val. m ust be increased to satisfy the requirements of cultivation. F. R. G.
F a c to rs in flu e n c in g th e c o b a lt c o n te n t of so ils.
E . B. Kid s o n (J.S.C.I., 1938, 57, 95—96).—A general relation is established between the Co content of soils and the Mg content of parent rocks. Manurial treatm en t repeated over long periods had little effect on the Co content of soils. Soils associated with
“ pining ” disease of sheep had low Co contents.
A. G. P.
E x c h a n g e a d s o rp tio n [in s o ils]. I I I . A p p li
c a tio n of th e p a r titio n r u le to ex c h a n g e of tw o ca tio n s. IV . A p p lic a tio n of th e p a r titio n r u le to ex ch an g e of th r e e c a tio n s . E. N. Ga p o n (J.
Gen. Chem. Russ., 1937, 7, 2801—2805, 2806—
2812; cf. B., 1938, 305).—I I I . Displacement from soil of adsorbed Mg or Ca by Ba, or of Ba by Mg, falls with diminishing partial adsorption capacity of the first catio n ; this is taken as evidence of th e existence of “ latent ” ions, i.e., of ions not taking p art in exchange.
IV. The am ount of B a" and Ca" desorbed from soil by aq. KC1 is given by a(S — I), where a represents the fraction of cations taking p art in exchange, S is th e adsorption capacity of the soil for B a" and Ca”
under the given conditions, and I is the am ount of
“ laten t ” ions. R . T.
B io g eo ch e m ica l p ro v in c e s a n d e n d e m ie s.
A. P. Vin o g r a d o v (Compt. rend. Acad. Sci. U.R.S.S., 1938, 18, 283—286).—The influence o f th e chemical Characteristics of soils, notably o f excess or de
ficiency of biologically active constituents, on the flora and on disease in plants and animals is discussed.
A. G. P . S o il c o rro s io n . F . J . Pu t n a m (Proc. Amer.
Petroleum In st. [Sect. IV], 1935, 16, 66—74).—
Means of predicting corrosion by acid and alkaline soils are described. Variations in rate of corrosion with tim e are examined. Ch. Ab s. (p)
O v e rlim in g in ju ry [to s o ils] in r e la tio n to ta n n in -c o n ta in in g m a te r ia ls . A. R . Mi d g l e yand D . E . Du n k l e e (Vermont Agric. Exp. Sta. Bull., 1937, No. 420, 28 pp.).—Certain types of acid soils, when heavily limed, become toxic to p la n ts ; neutral and alkaline soils do not show this defect. In some cases, notably the leached A 2 horizon of podsols, injurious effects occur even when th e am ount of CaO added is < th a t required for neutralisation.
Tho toxic action on plants is not due to nutritional disorders, bu t is associated w ith org. m atter, probably tannin, and is difficult to eliminate. Certain tannin- bearing p lan t tissues and tree barks, after acid- leaching, caused injury to flax resembling th a t due to overliming. Sol. tannins did not cause toxic sym p
toms, b u t difficultly-sol., tannin-like derivatives became harm ful when activated b y CaO. These effects are largely restricted to th e pyrocatechol
ty p e of tannins. A. G. P.
R a p id c h e m ic a l te s ts fo r c o a s ta l p la in so ils.
J . B. He s t e r, J . M. Bl u m e, and F. A. Sh e l t o n
(Virginia Truck Exp. S ta . Bull., 1937, No. 95, 1431—
1487).—The reliability of various rapid test m ethods is examined. The solubility of Fe, Al, Mn, Mg, and Ca phosphates in aq. NaOAc (pK 5-0) is closely correlated with the val. of these compounds as a source of P for plants. A. G. P.
R a p id field s t e s t s fo r so il fe rtility . C. R.
v o n Stxeglitz (Proc. In t. Soc. Sugar Cano Tech., 1935, 5, 631—636).—Methods for P , Ca, Mg, K , N, Al, and Mn are described. Vals. for Al aro inversely correlated with p a and afford a supplem entary index o f CaO requirem ent. Ch. Ab s. (p)
D e te rm in a tio n of soil-pn u n d e r n a t u r a l field c o n d itio n s. M. Aoki (J. Agric. Chem. Soc. Japan, 1938, 14, 165— 177).—The p a of soil suspensions determ ined by the Itan o electrode (B., 1936, 657) was usually either slightly > or < th a t obtained by the usual quinhydrone electrode, b u t sometimes there was a marked difference. For most soils a remarkable change in e.m.f. wets noticed within 2 min. of insertion of the electrode. There is no regular relation between pn and moisture content of soil. J . N . A.
E le c tr o m e tr ic e x a m in a tio n of s o ils. v o n
No stitz (Ernahr. Pflanze, 1938, 34, 114— 116).—Tho electrical conductivity of soil serves as a measure of its productivity. Addition of KC1 to black-earth soils produced little change in conductivity, b u t with
soils approaching podsolic types conductivity in
creased considerably. A. G. P.
L a b o r a to ry la y o u t fo r r a p id s o il a n a ly s is . 0 . Ar r h e n iu s (Zuckerrubenbau, 1937,19, 161— 165;
In t. Sugar J ., 1938, 40, 149).—A special laboratory has been equipped by the Swedish Sugar Corp. for dealing w ith 500 samples of soil per day, having in view the restriction of time and effort to th e min.
possible, using a line of workers each carrying out a particular operation. The various stages involved in th e determ ination of P 0 4" ', N 0 3', and p a are
described. J . P. 0 .
S o il a n a ly tic a l m e th o d s em p lo y e d in Q u een s
la n d . H. W . K e r r and C. R . v o n S t i e g l i t z (Proc.
In t. Soc. Sugar Cane Tech., 1935, 5, 624—630).—
D yer’s m ethod for P 0 4" ' gives erroneous results on highly laterised soils and th e Truog-M eyer procedure is preferred. Field and laboratory tests for P 0 4" ' are closely correlated. The replaceable K val. gives a substantial negative correlation for vals. above a well-defined limit. Ch. A b s .
(p
)F e r tilis e r s a n d s o il s tr u c tu r e . J . Ap s it s
(Ernahr. Pflanze, 1938, 34, 109—114).—Fertilisers had no appreciable effect on the structure, aeration, or H 20 content of soil. A . G. P.
S o il f e rtility u n d e r field a n d g re e n h o u s e co n d itio n s a t E v e rg la d e s E x p e r im e n t S ta tio n . R . V.
Al l is o n, A . Da a n e, R . E . Ro b e r t so n', F . D.
St e v e n s, a n d J . R . Ne l l e r (F lo rid a A g ric. E x p . S ta . A n n . R e p t ., 1933, 165—169; 1934, 91—93).—
F e r tilis e r tr ia ls are reco rd ed . Org. N m a n u res were m o s t e ffe c tiv e w h e n u se d in c o n ju n c tio n w ith e n e r g y (ca rb o h y d ra te) m a teria l. Ch. Ab s. (p)
C h em ical re a c tio n s in f e r tilis e r m ix tu r e s . R e a c tio n s of ca lc in ed p h o s p h a te w ith a m m o n iu m s u lp h a te a n d s u p e rp h o s p h a te . K . C. Be e s o n and K. D. Ja c o b (Ind. Eng. Chem., 1938, 30, 304— 308;
cf. B ., 1938, 202).—Storage tests are reported for three types of m ixture : (a) calcined phosphate rock (I) + (N H 4)2S 0 4 (available P 20 6 : N = 2 : 1); . (b) (a) - f superphosphate (II); (c) 6-12-6 [% N : avail
able P 20 5 (total) : K 20 ] complete fertiliser, from (I), (II), (NH4)2S 0 4, low-grade KC1 (66%), and filler (sand). All m ixtures lose N (NH3) on storage, except when (II) : (I) is > 1 : 2. R ate of loss depends on initial H 20 [with 0—1 and 3—7% of II20 , N lost (84 days) was 0 and 8—10%, respectively], on R .H ., distance from surface, and other salts present [loss with (c) is > w ith (a)]. Tests with synthetic st
and p-Ca3(P 0 4)2 and hydroxyapatite show th a t the loss is m ainly due to <x-Ca3(P 0 4)2. Storage of a m ixture of (I) and (II) before addition of (NH4)2S 0 4 increases th e loss. I n (a) H 20-so1. P 20 5 increases on storage, b u t citric-insol. is unchanged. In m ixtures of (I) and (II), citric-insol. P 20 5 increases with tim e of storage, am ount of (II) (up to 1 : 1), R .H ., and also when (NH4)2S 0 4 is added; H 20-sol. P 20 6 decreases on mixing, then increases, and finally decreases, but when (NH4)2S 0 4 is present it falls slowly; it is in
creased by increasing (II), lowering the R .H ., and in absence of (NH4)2S 0 4. Increase in particle size decreases the N loss in (b), b u t in (c) loss with CO—
80- > 100—150- > 20—40-mesh. In all m ixtures
C l. X V I.—AGRICULTURE. 703 th e am ount of H 20-sol. P 20 5 is unaffected by the
particle size, bu t the- am ount of citric-insol. is less with smaller particles'. I. C. R.
C o m p a ra tiv e effects of s u p e rp h o s p h a te a n d b a s ic s la g a p p lie d in th e fo r m of to p -d re s s in g s [on so il]. E . Tr u n i n g e r (Superphosphate, 1936, 9, 46—50).—In pot cultures in soil of p a 5-2 and de
ficient in Ca and P, superphosphate was more effective th a n basic slag, whether H 20 was supplied from
below or above. Ch. Abs. (p)
A v a ila b ility to p la n ts of p h o s p h a te s a d s o rb e d b y so il. S. N . Ale sg h x kan d E. Ig r it s k a j a (Compt.
rend. Acad. Sci. U.R.S.S., 1938, 18, 299—302).—The yield of oats and the uptake of P by th e plants was m arkedly increased by treatm ent of soil with CaO, N a2S i03, or org. m atter when superphosphate (I) was given; the availability of native P in the soil was not greatly affected by these supplements.
Yields obtained when (I) was applied later than, were
> when applied with, the org. m atter. Best results were obtained when org. m atter was preceded by CaO an d followed by (I) treatm ent. The effect of the supplem entary treatm ents is ascribed to the relative ab ility to displace P O /" from the adsorbed state.
A. G. P.
P la n t n u tr ie n ts a n d p in e g ro w th . S. L . Ke s-
s e l l and T. N. St o a t e (Austral. Forestry, 1936, 1,4-—13).—Soils from “ sick ’’ areas in pine plantations are generally deficient in plant nutrients. Analyses of sick and healthy nursery stock show notable difference only in the N a contents. The N cycle of the soil was not a factor contributing to “ sickness.”
Beneficial effects resulted from application of super
phosphate, the action of which was not improved by supplem entary treatm ent with N-, K-, or Ca-con- taining fertilisers. Rosetting of young pines was largely prevented b y spraying with aq. ZnCl2. Direct applications to soil were less satisfactory. A. G. P.
A v a ila b ility [to p la n ts ] of m a g n e s iu m in m a g - n e s ic lim e s to n e s , s e rp e n tin e , o liv in e, a n d m a g n e s iu m a m m o n iu m p h o s p h a te . G. F . Le a and J. B. Sm it h (Amer. P otato J ., 1938, 15, 4—9).—
Potatoes respond readily to applications o f Mg compounds. The availibility of Mg in the limestones varied considerably ; the CaO/MgO ratio was n o t a contributory factor. Serpentine and olivine and, especially, MgNH4PO, were effective sources o f available Mg. High levels of K supply in soils
accentuate Mg deficiency. A. G. P.
A m o u n t a n d v a lu e of p la n t food in th e s o lid e x c re ta of P h ilip p in e c a ra b a o s . V . Vil l e g a s
an d L. A. Yn a l v e z (Philippine Agric., 1937, 25, 841—846).—Analyses and other relevant d ata are
recorded. A. G. P.
A m o u n t of faeces v o id ed b y P h ilip p in e a n d N e llo re c a ttle a n d f e r tilis e r c o n s titu e n ts co n ta in e d th e re in . V . Vil l e g a s, L. A. Yn a l v e z, and A. El e f a n o (Philippine Agric., 1937, 25, 833—840).—
The o u tp u t and analysis of faeces from various cattle are recorded and the annual cash val. of the m anure is
determined. A. G-. P.
E ffe c t of s u p e rp h o s p h a te in c o n s e rv in g n itr o g e n in co w m a n u r e . A. R . Mi d g l e y and V . L.
We is e r (Vermont Agric. Exp. Sta. Bull., 1937, No.
419, 23 pp.).—Losses of N due to leaching, volatilis
ation, drying, and freezing during the handling and storage of cattle manure are discussed. Addition of superphosphate diminishes these losses, especially when i t contains considerable am ounts of CaS04.
The CaS04 has little effect in itself, b u t supplements the action of superphosphate. A. G. P .
R e p o rt of C h e m ic a l D ivisio n, 1934. R . R . Fo l l e t t-Sm it h (Div. Repts. Dept. Agric. B rit.
Guiana [1934], 1935, 81'— 101).—Flood fallowing decreased the acidity of surface soils and increased th e available F e of surface and subsoil. In some cases there was loss of org. m atter and narrowing of th e C/N ratio. Crumb hardness was lowered. In the lower layers more F e and less Mn tended to become available. Storage of soil samples lowered their content of available Fe.
Crumb hardness was unrelated to the am ount of available Fe or to th e exchangeable or H 20-sol.
K or Mg, bu t increased w ith the proportion of ex
changeable or H 20-sol. N a and decreased with th a t of Ca. In general, presence of large am ounts of bi
valent bases in the soils was associated with smaller am ounts of univalent bases, and vice versa.
Application of superphosphate a t th e tim e sugar cane was planted had no consistent effect on the composition of the leaves.
The mineral intake of pineapple plants in sand cul
tures was notably high in the 6— 9th months. Pine
apples require high IC and low P manuring. During ripening of pineapples, the Brix val. and -t] of the juice increase and acidity diminishes. Ripeness is more closely related to the Brix : acid ratio th an to the B rix val.
Analyses of Tonka beans are recorded.
C h. A b s .
(
j>)
D e te rm in a tio n of th e e q u iv a le n t a c id ity an d b a s ic ity of f e r tilis e r s . S tu d y of m ix e d in d i
c a to rs . W. H. Pi e r r e, N. Th l l y, and H. V. As h-
b u r n (Ind. Eng. Chem. [Anal.], 1938, 10, 72—76).—
T itration curves of acid extracts from various com
mercial fertilisers show th a t the buffered portions extend from approx. p a 3-8 to p a 4-6 (mid-point
^-4-3). In the determ ination of th e equiv. acidity and basicity of fertilisers th e indicator used should therefore give an end-point a t this p a. The behaviour and p a ranges of various mixed indicators are dis
cussed ; the best indicator for this determ ination is a m ixture of bromocresol-green and Me-orange, which shows a definite colour change a t p a 4-3 and is satis
factory in turbid as well as in clear solutions. Its advantages over Me-red -f- bromophenol-blue are discussed, and directions for its prep, and use are
given. L. S. T.
D ire c t d e te r m in a tio n of a v a ila b le p h o s p h o ru s p en to x id e c o n te n t of f e r tilis e r s . W . H . Ma c- In t i r e, W. M. Sh a w, and L. J . Ha r d in (Ind. Eng.
Chem. [Anal.], 1938, 10, 143— 152).—A direct procedure for all types of fertilisers has been worked out. The solvent is m-NH4N 0 3 + , 0-05m-NH4 citrate o f p a 4-2. The procedure involves prior leaching with th is solvent, digestion of th e leached residue with solvent in a current of steam, and pptn. o f N H 4
phosphomolybdate from the two combined extracts by the official method. Removal of N H 3 from the digestions of basic phosphates gives constancy of pa and complete solubility, whereas a rise in p a and partial solvent action occur in boiled digestions.
Inclusion of citrate in the N H 4N 0 3 solution is essen
tial, the citrate concn. being only J of th a t of the official ex tractan t and insufficient to prevent quant, pptn. of the P 20 5. Prelim inary washing with the solvent effects P 20 6 removals in the range 30% for basic m aterials to 98% for superphosphates. CaS04 is alm ost completely removed. The numerous ad vantages of the proposed m ethod are discussed. The behaviour of the official citrate solution and the pro
posed solvent are compared for samples of widely varying types, origin, and concn., and the effect of composition, size of sample, particle size, common ion, period of digestion, raw rock supplements, P 20 5 transitions induced during the analysis, and varying proportions of the basic forms of phosphates formed during commercial processes and ageing has been
investigated. L. S. T.
In so lu b le re s id u e in p o ta s s iu m c h lo ro p la tin a te o b ta in e d in a n a ly s is of c e rta in f e r tilis e r s fo r p o ta s h . H. R . Al l e n (J. Assoc. Off. Agric. Chem., 1938, 21, 134—140; cf. B ., 1937, 478).—The am ount of insol. residue is inversely cc the ignition temp., except when S i0 2 dishes are used. Tho am ount of K 2P tC le is oc th e ignition temp. P t dishes are preferable to S i02, and ignition of tho sulphates a t 750° is preferable to ignition a t a lower temp.
E. C. S.
[D e te rm in a tio n of] m a g n e s ia in w a te r-so lu b le [f e rtilis e r] c o m p o u n d s . An o n. (J. A sso c . Off.
Agric. Chem., 1938, 21, 77).—The solution is neutra
lised to Me-red, heated to boiling, and treated with (NH4)2C20,j while still hot. After keeping for 4 hr., the ppt. is filtered off and Mg determ ined in the filtrate by the official method (A.O.A.C. Methods of Analysis, 1935, p. 124). The m ethod is applicable to MgS04, K ,S 0 4-M gS04, and kieserite.
E. C. S.
L o sses of c h lo rin e in d iffe re n t [a g ric u ltu ra l]
m a te r ia ls w ith v a rio u s a s h in g te m p e r a tu r e s . T. A. Pic k e t t (J. Assoc. Off. Agric. Chem., 1938, 21, 107— 108).—Provided th a t Na2C 03 is present in excess, the loss of Cl is negligible during two ashings of 1 hr. each a t 600°. Many of the agricultural materials analysed could be safely ashed a t 650°, w ith th e same precaution, bu t none could be ashed a t 800° without considerable loss of Cl. A large am ount of Cl was lost even a t 500° when an excess of N a2C 03 w'as not present. E. C. S.
P h y sio lo g ic a l p h a s e s of p la n t n u tr itio n . J. R.
Ne l l e r (Ann. R ept. Florida Agric. Exp. Sta., 1933, 194— 195 ; 1934, 108—109).—Soils containing up to 90% of org. m atter responded to relatively small amounts of green manures, probably through micro
biological effects. The C and N balance of these soils and the effects of P manuring are examined.
Ch. Ab s. (p) U n so lv ed p ro b le m s of a g r ic u ltu r a l c h e m is try . C. A. Br o w n e (J. Assoc. Off. Agric. Chem., 1938, 21, 26— 43).—Wiley Memorial lecture. E. C. S.
In te n siv e s y s te m of g r a s s la n d m a n a g e m e n t.
J . P . Dr e w and D. De a s y (J. Saorst. Eir. D e p t . Agric., 1937, 34, 225—247).—On intensively manured grassland P and K contributed approx. 50% of the to tal increase in live-wt. production and carrying capacity. The effects of N fertilisers were apparent chiefly in the early m onths of the normal grazing season, and the val. of late applications is doubtful.
Systems of rotational grazing are examined.
A. G. P.
C o tto n n u tr itio n . W. A. Ca r v e r and R . M.
Cr o w n (Florida Agric. Exp. Sta. Ann. R ept., 1933, 131—-133; 1934, 118).—In Florida soils org. and in
org. N in mixed fertilisers were equally effective for cotton. Yields were improved by previous cropping with peanuts bu t not w ith maize Ch. Ab s. (p)
In flu e n ce of p o ta s s iu m a n d p o ta s s iu m s a l t a n io n s o n fo r m a tio n of fib re ce lls in flax . K . Sc h m a l f u ss (Ernahr. Pflanze, 1938, 34, 100—103).—
K manuring increases the diam eter of flax stems and the succulence of the fibre cells, th e latter effect being very marked w ith fertihsers containing Cl'. The no.
of fibre cells per stem section is greater with S 0 4"- th an with Cl'-containing mixtures. Apparently an ta
gonistic effects of S 0 4" and Cl' m ay be related to differences in th e action of these ions on the H 20
economy of the plants. A. G. P.
T re n d s of y ie ld in m a jo r w h e a t re g io n s sin ce 1885. I I . I r r e g u l a r , s ta b le , a n d d e c lin in g tr e n d s . M. K . Be n n e t t (W heat Studies, 1938, 14, 223—261).—W heat yields are tending to decline in the central plain of N. America, owing to adverse weather and to natural conditions which restrict th e use of yield-raising methods of cultivation. In the world excluding Russia and China, the upw ard trend of yields has become downward owing to a drift of wheat acreage to low-yielding land.
E. A. F.
In flu e n ce of c a lc iu m c y a n a m id e a n d so m e c y a n a m id e d e riv a tiv e s on p la n t g ro w th . S.
Te j im a (J. Agric. Chem. Soc. Jap an , 1935,11, 1055—
1074).—Dicyanodiamide, guanidine nitrate and car
bonate in am ounts equiv. to 0-007—0-0035% N in H 20 cultures were injurious to barley and, less so,
bonate in am ounts equiv. to 0-007—0-0035% N in H 20 cultures were injurious to barley and, less so,