|Table of Contents|
The methods employed in the investigation and effect of imperfect stand on yield of hops
Variation in the yield from individual hills
Relation of number of vines per hill to yield
Comparison of actual with possible yields on 1 acre
The so-called "bastard" vines
L. D1EP.\RT11N T ()I: .\(ki I AVT 1\ 11*
Ill'l, 1 t \ l U 1.F I IN II I fl lI, Nor~br 56.
S)1E ('()NI)TI( NS INFLtTENCIN('
TIlIE YIEL ) OF Il PS.
W .~~ ~ 11. .T..(.K.l...l. 1. .as<- -o o
.\11E:siI TI( )1 P )N.C ExiTwr.
10 tI -P N N 1 TteT
BUREAU OF PLANT INDUSTRY.
Chicf of Ifurcau.ll t la aT G lIn .Y
A( iStnt ('hef of lniaim G. 11iluAM O P W1:1
Editor, J. E.
Chief Clerk. .11 r11: E .al: ,.
[ i t r...;
SO)\11 t')\I)1 IoNSFTII) I 1V TIll
YIEL) ()F I) I0 .
I eII ltt o 1 Iv lof tihn ta Illat be'llaW ai H : 1 tV
10:11'ia i Itlaof I, ;II:IIala al te ai I I l 1 :11 1~r.a aa ;tta s ;tlr I ~l1
' ~ta l otl he It H III1 1 III P II
D cillt l fe l 11 I If-1.
I litiI t
I I it r } 'I Ilf1
4 SU.111 CONDIIiTNS INFLUENCING TIHE YIELD OF HlOPS.
The figure. givell ill tlls table were taken at tei-vear intervals, and
in the absence of those for tle iiterven ing yearl they are of little
value in determ in in g either an increase or a decrease in the average
*nnual vichl. Ausiuniinig. however, that the apparent diinilution of
vieli for tile State of California as indicated by the table was real, a
thoroiigh silyv of an in11 dividual acre inl the central part of the State
wes beguni in 1909 for the purpose of determining sonme of the factors
which mi ight be responsible for dimiiiiiiui hed production.
The results of this study clearly indicate that closer attention to
certain (ultural details should result in a substantial increase in yield.
THE METHODS EMPLOYED IN THE INVESTIGATION.
'Ile acre selected for studV represented, as far as inspection
alone could deteriiiiiie. the average of conditions existing in several
contiguous fields of hops aggregating about t0 acres. The soil, a.
rich sandy loan. had beenii under hops contiiuiouisly for the last ten
years. The rows were 7 feet apart. running from east to wvest, and
the hills Iwere approximately 64 feet apiart in the rows. The hops
were trained on strings about 18 feet long. depenidiiig from the wires
of the usual type of high-wire trellis.,
When the crop was ready for harvesting, a plat was made of the
entire acre anid a definjite number aSsiild to every hill. The hops
were then picked from each hil1 separitely. weighed, and the weight
recorded opposite the lulber a-signed to that respective hill. The
nhiber of vines to the hill, the occurrence of male. dwarf.** bastard,"
nonproductive, aid missing hill aid the general characteristics of
tle produCt of each hill were also recorded.
EFFECT OF IMPERFECT STAND ON YIELD OF HOPS.
Wheni the observatiois were ahulated it bec;ine evident that the
yield had beeni heavily reduced through the (ecurreice of a large
Ililiniber of 1o11productive and1 missing l1lls, as will be seen from thle
Hills producing hop __-- - - - -- - - -- -- S5
Ilills having vines with no hops 42
Missing hills _
IHills with dwarfel vines 1
Hills hli -ig usiha rd" vinles 5
Ilills ha li1g iionly 1110 vic in'es 10
I)eluct inug tle numn1 ber of untl1c lhlS. tlie presence of which i- held to
be iecessar* v for tle p"oper developmelt of thie crop. there should
hiave been on this anre 9.-)7 productive hills. as aa inst 853 hills
See Fna I'llners' Bulletin 304, p. 14.
T ( I N1 I n of ).N I : o Ital :sol of NtoI
11ll1 Iei i o IIIEp, g II I 12 T
0--T11 117 1
IP Fll~~11a 1 0 1
1:titt'0 toI *p: r, 11 111 'lit'llalY 111I a
I':Iill~~~~It at )I'dwt 1'o
I: I I rt -- I' I it k I------
6 SOAE CONDITIONS INFLUENCI.NG THE YIELD OF HOPS.
VARIATION IN THE YIELD FROM INDIVIDUAL HILLS.
A wide variation was observed in the yield from individual hills.
This ranged froim a few ounces in some cases to as much as 18
pounds in others. In iiiaking the records the weight of green hops
was taken to the nearest half pound, and the results have been put in
tabular form, appearing in Table II. In the columns marked
Yield the weight of green hops is given to the nearest half pound,
aid in the other two columns is given the number of hills, each of
which gave the yield opposite these numbers in the adjacent column
to the left.
TABLE IL-umbor (of hills iring rarioys yiclds of hops on th'erpcrimnntql
acrc in California.
yield. Hills. Yield. Hills
Pounds. Number. Pou nds. Numbr.
0.3 1 9.5 24
1.0 30 10.0 :1
1.3 34 10.5 Il
2.5 30 11.0 24
23 33 11. 10
3 0 32 12 0 20
41 41 l..
43 41 13.
4 3 13.3 I
0 00 14.0 11
5.5 44 14. 3
1.0 44 13. 2
5 .1 13 1
7(0 49 l6. 0 0
7i 15 3
80 o 1.0, 1
Is 53 17.3 1
9. 0 31 1S,0 3
The total yield of this acre was .207.5 pounds of green hops. and
this divided by 853, the number of bearing hills. gives 6.104 pounds
as the average production per hill. Of the entire iiniber of hills.
473 were below the average and 380 hills were above the average
production. Also. the average production is only one-third of that
reached in the case of a few hills.
According to the quanltitv of hops produced the hills may be
roughly divided into three classes, or groups: (1) Those yielding
le>s than 6 pounds. (2) those yielding from 0, to 12 pounds. and (3)
those yielding mnore than 12 pounds. The first group consists of 429
hills, or1- 50.1 per ceit of the entire numjiber. and these produced only
1.,So.5 pounds. or 26.5 per cent of the entire yiel. The second
group has 384 hillk. or -5 per ceit of the entire niuiiber. and the pro-
duction was 3.261 pounds. or' 62.6 per cent of the entire yield. The
tiird grolp conisists of I0 hills, or 4.7 per cent of the entire number.
and i hop)-, produced weighed 566 pound-. being 10.8 per cent of
I (ir. 5t1
thi I *\ i. v I lu \T I 1 1 1 I I \ u I l i l i, a 14-- I I I (-( l p.
10 le:I t w l pl I 0.111 ftwi11104 ( i t'nC iC(le ilonI f pt t* \
rc8 (4 ot O vci fromi (iw hil I 4 of 1 vo e tire tivld. .\A -Il vof Ie b11-,
Oit thlt ibi ll t 1 1 I 3ivsi- Ile ar\ te t*-, prd4 I Vf11
I PII I1II'ty trlifl I re" :1 ;1le i-v m* reph'I-Vit t lt' I 11". 111
)III a rk.i i fell II I I 11111 a0 lilt 1 Ill1 I v c(o ot O i t e t 1e
RM P t'O Ilt 1 11 a 1(I Itc f 1' c Il 1 1,llet *t \p I, w(1 ( ;II' r e f vl I il 111 1
PER L.#/4// Q." -'/FLD /6' 710//VLz5 1E ,/// A/LL.
gg 0 AW.Z5s or4 -. 7% oA rwe synwe vese
wwca24er aWJ o.A7/o ? /.e 6 % or evrtr YedLV.
4 /-,/ Z W1 7"// 0, $ Tf 'r/4' FW AY'1864
L0*'tAP L +Mwr OF" )"'tZLD 0.6' Pot.//VD PER9 A,ZZ
lIhl. II 1 'iiIn 2.** x : hutt v.ins.I i .toa.. of hex~ 'i i a. it* lgnwhe tll' tf 101* in
iaf (1e 111 4id th1 t it'Y vftii i. I ti a lit-. x ithelof t'h1t illl oll hIt
hill" f who t l 1ur IiI' w i*l of vIlithlg' ax htnailwd. the t picl
hII -H. if It 11 rc pV'' (4) \i i lf IIt h \pi If.*] to ()n*Ilf 111$.O wn'l,
I1 e *l t y \ o f t iplanI 1 H 11 w it r pet to .1 v d lt's
1,411il 10 I f u th'ldlc ig_ a:11,14 1 10 to plO li'il. I t, W I' I
t'lofl, a0 il I' il n eu ;(( ( oI) to) h I I I k I Iln 1i 1 1"
010~~ lrp J (bl i ll.'0 01 ol lI_,iyIfT' -tf~ :11e m 04IIVIk 1ilO-
The faIct -1h0,1b1 not h 1 iifh of thIalt I t v rnee ,vi vII ftor IthIis
acre. I.1 nall-. per h ill. lie- In-t altove Ihlth lutxer liilit of vihluI ii
ICur. 36 1
8 1SOME C'ONiDITIONS INFLCIENCING THE YIELD OF HOPS.
the second group. If through better methods of handling and closer
attention to the details of cul tire the number of hills in the first
group c:aIn be imaterilly diminished. the average yield for the entire
nere will be corre-pondilglv advainced toward the ipper linit of
yield in tlie second group, and the total yield thereby substant ially
increased. Inl the following pages soie suggestions will be given as
to how this may be accompih'shed.
RELATION OF NUMBER OF VINES PER HILL TO YIELD.
''le recordls obtained from the acre uider oh-lervatioi show. fur-
ther, that tle nuber of vines trained front the individual hills
v'aied front one to eight. The distribution of the hills according to
the number of vines is shown in the following:
Hills living one vine- 54
ills luviing two viies ----------------113
Hills having three vines --- 11
Ilills having four vines 1NI
Hills having five vines --1
Hills having six vines --
Hills ha cing seven vines 8
Hills having eight vines ------1
Total __ -M
Several explanations of the variation in vines to the hill may lie
advanced. Among them are the recent replant big of certain hills,
inl which case the\, would iot have the vigor of older hills: the weak-
eninug of the roots of some hills by disease or the attacks of insects:
the exhaustion of the vigor of others through lollg-contiuted pro-
duction ; the breaking- off of a portion of the vines inl cultivation; the
destrtiction of some vines by the wind: or the cIttiig off of too many
vines at the time of training. What sees most probable is that
through the carelessness and negligence of the workimeni the proper
num titbelr of vines wa ot trained. It i- pirobable. also, that indi-
vidual differences in vigor and productivenes- should le taken into
Ihie relation between the number of vines per hill and the yield
per hill is shown in Table III.
1 Cir. 561
I 11 It III. I i '' j,'a s l : I p / N W W "
1 1 1 II 1 Hin
% 1 2
110II' ( IIId. 10 il'e ;
It n to t 1 -111 al'sf i i n I AN \ ivlJ It. li 4 uih i t" Ole
"muiu ta t tell Wi ine htI i ll I II hitI'd IVA Ii h -i ~ 1 W~i I N thi '11
I~~~~~~ ~ ~ ~ tt 11 1 1 W"IH4 JJI M I %:AL
h lI t ~ll l aill Q-i t\X"" IN'l imiI own Li 12th jo1 'ii t~ Ii
')f i tt-prc
CO 111111 )vcnl, lit ,bu1 1ln 1: P. 11 'f Jl m lm p 1
lU t t o ( t1he p10* lt~ Im of11 1-' 101'1 vlq , 16 q
Io ut 1) l". 2:. and I1 611 ill'm I1Q 1. and 1. n
10 SOMIE CONDITIONS INFLUEN'CING THE YIELD OF HOPS.
respoctivelY: (froim colunn 3) 15, 12, and 13 hills produced 2.5, 3,
and 3.3 pounds each. respectively; (from column 5) 14, 18, and 18
hills produced 7. 7... and 8 pounds each, respectively. From column
1 it appjIar)i that no 1-vine hill produced more than 4 pounds, and
from column (; that relatively few 6-vine hills produced less than
;.. pouIds each. The balance of evidence, therefore, is entirely in
favor of a much larger total production when 6 vines to each hill
are trainled than with a smaller number.
COMPARISON OF ACTUAL WITH POSSIBLE YIELDS ON 1 ACRE.
The actual yield of hops on the acre studied was 5,207.5 pounds.
and the mean yield per hill 6.104+ pounds. Had there been a full
stand of 937 bearing hills. with this same average yield p er hill, the
production on the acre would have been 3,841.5 pounds. This is an
increase of 12.1+ per cent over the actual yield.
In a similar manner. the possible yield per acre has been calculated
for each number of vines trained per hill. For comparison the results
have been brought together in Table IV. which follows:
TABLE IV.-PO.'xxiblf Ii"d fill / 1rec (of hops., according to the number of vines
trained. with th cor-cr(ponding inrcrasc or d(creaS of the possible over the
Numbr of tletual Averge Average 1'ssible decrease of
yield 1 yield t) yield to possible
hills. itld. the hill. fh vile, the acre. over actual
Pounds. Pounds. Pounds. Pounds. Per ce nt.
1 -.---- 54 71.3 1.324 1.324 1.257.0 a75.8+
2 113 293.- 2597 1. 29S 2, 433 a -
3. 133 33.3 4.337 1.445 4,150.5 a20 2+
4. . -- .--- 1,1- -.0 6.279 1.569 0W,009.0 b15.3+
5-............. ...... 1s 1.4w..> ?91 1.5"3 7.576 I5 b45.4+
.... 1,.1... L 9 1 495 S, 04.3 665.2+
---- -l. 10123 1. 0 ......................
S.... .. < 1
Ic rease. Iwrl .ase Number of hills too small for consideration.
The average yield to the ill was determined in each case by divid-
ing the number of pounds produced by all of the hills having the
same number of vines by the unimber of such hills. The possible
yield was then obtained by multiplying the average yield per hill
by 937. the number of possible bearing hills to the acre. It will be
oh erved that the possible yield in the case of the hills having 1, 2,
and3 vi11es. respectively, is very much less than the actual yield,
which wa 3207.3 pounds. Also, in the case of the hills having 4, 5,
and ( vi ne-, re spect ively. the possible yield is far in excess of the
actual. bein 3.2- per cent greater for the 6-vine hills.
tll II'I't W 1"14 e 1 4 llf ill6 a l 111- to H l ll. I11* :11 f Ir l.t '<'
-fa il(. it *Y- lyt' o tih i 1il I % :1 I 11i1 Tl**1 1a,'
(h* l Ir lin or'i' ll il( l H IA, d A i .1i 11,0 "l
I't~ii ii 1011- felllt tu \lc i Iii il 111I 1 :I II i u .' I u lluU.* I t's a at itI
livintThg, in A N am, W K** IIIn :11 \ \e III;[
iu 1" I*( i 11) < ti n'it ig \t K il IV a & t':-1 iut l a- 1ah ihIV
m" It S % 1" IS av ill d t In a oft I l rlicl:0 01:1 i) till 10tl.
0,~o l I n lv c tolh' Nd c e il Nior So t'n a1-' I lit, re u t** Il ll \ 0 tt
1I t' \iliti' u i l H IP ) 1 i' I- i ( I I i ti Iiul \ II l Icr o I it 01, at'
W311,'- 14 lit giuul l. t ml 4 0il ,o r W r l i "A a tal ic i' to)
1 ) I t ill)P houq (il i. juu t Mil ll colid-c ia 1rialIv atIi cc Ithe
c 111aui o t )l- 1m, 11' -'In g HIT -- al l. 11tI t Ili' il: 1i'o w Ii :i a
Ill flfd 1 jtu ll Op hu ld -in Ela iitI t n1'
p t't itlcn i1 1 1 1 'it In I' ii ii I"lHA I, i
)0011i Ii th-c s \i 14 -t I l if 1 1\ 1ul al1101~~a['r h its lxc
lile 00m1 to nl1tW10 -llan anitl It vrolm" ar lojuli oehll C\*; inT i
tillcu tiirt lu-l, 1 h 4 it I 'lit l<' ; i t h-I g Oi the acrei
N tic ti [ia- furniplic huli laI t f hr t i v l' r ati 1-I.
THE SO-CALLED -BASTARD" VINES.
Ill -uiliat' l-'d ju 11- h Iiat \ um .1 iyII' la n hiii ili l l 1 v ahs
ko o h) v hit c u jl-P it itit am tic'i Qalllul l. ( )** Itu w *lr
tIIl' t Imll 111Imrli i th';rlf xxt m' 11:11ill l i I I hu-\ i~ tI 0: 1 t tli'
11>11:1 Im ll 1111**0.' 100* i 1 Ithih :1 ltd' i umi'jll i uti' 1'l' :lu l
ulilc m0:1'ait flow \vv oin l l it* 1. p rl
Iiicr \ t he ill b -xv i n ""du tha ) t uxroler pI1slt.iIlx, uditl oth r yar Iaand ll'
Ill -t'tu s Ily M litrtl' ofi ir i nn iifit" V ''- of pidlluh li ng, .ulli
Ith liL-tilIatv l wxr- pirtlillv tlii- alliuom il 1\ a- I : 1I"M IIn -ow
1t' 14' iI' ct-0. 11ViUt1 (If h ilI Illi lri-mjuiVIIIx 11itl i lim u Weau lit ir
A ll itiu i tpiii h iiu' llf 1 .m- e 14 1 1- xx l*' ill-' O-i-il
list l fia1ui't. ll wp r il m Io I10 tu lic\il _t It : i Illi-
und4.c-ir'aleu chliw 'I't Ic tulax Wuu inim uliu'c thni~i tllw iiu~ll ir
110H IW 41 11 IN <:l'**ng orill mn tw '' \ in 1ic l 1II ]!t' at < 'i 11
but' of1 cn'lig- xxmu luii frt"i iw _f th Im,-Iwirl Id t- atoi
ilgl "&d I"( a : lus >IIII 11 a' llt y 1 4 Iu ". IP a lii I'til 'r im It vinl .u r,
ct~it inW- ( al lu' inmo 11. i 1n.uI *rM l l c-, t .o .. 1 i 6
ttah1 igaIM uii11 Ofi 1110 (Wi-'_illtal 1&HA~~ 0 11uiu "lf 111hi 'l V "A Ix u-ru ta 'u lit
\e i o\f-t thui- taut car- -limUlIl lmu alkui wi hiruxu-i hu t- t 111v1 11twli'
yivak. If. 'rim, mut. Nx \ n.i-sam.
12 SOME CONITIONS INFLEFN'I-NG THE YIELD OF HOPS.
the roots as soon as they are observed. In this way their perpetuation
mnay be prevented and the loss in yield due to their occurrence avoided.
A critical study of vield on an acre of hops in California selected
asrersenting the average condition of 600 surrounding acres shows
that, owing to the occurrence of a large number of nonproductive and
miissing hills, the nctual field was only 87.9 per cent of what might
he expected within a perfect stand.
The yield from individual hills was found to vary from 0.5 to 18
pounds. Owing to the large nmnber of low-vielding, hills the average
yield per hill for the entire acre was reduced to 6.104+ pounds.
Th'le number of vines trained to each hill varied from one to eight.
Athe number of %-Ines per hill increased, the average yields of the
hills having the same number of vines were found to increase in
approximatel 'y the same ratio.
Assuming a full stand of (957 hills with 6 vines trained to each hill,
the calculated possible yield is W5.2+ per cent greater than the actual
yield on this acre.
.1 Bastard or mongrel hills should be dung out and destroyed,
as they are of no value and diminish the total vield.
ASecretary of Agriculture.
WASmscToN, D). C., Mlarch 7, 1910.
UNIVERSITY OF FLORIDA
3 1262 08928 9762