Effect of Six Four-Year Rotations on Yield, Quality, and Monetary Return of Sugarbeets
3. Sugarbeets wheat barley alfalfa fallow 4. Sugarbeets potato wheat barley
5. Sugarbeets wheat barley soybeans 6. Sugarbeets wheat barley oats
T h e land in rotation 1 was kept black the fourth year. T h e legume in rotation 2 was a mixture of alfalfa, sweet, red, and alsike clovers, plowed u n d e r in late J u n e and the land fallowed the remainder of the year. T h e first crop of alfalfa in rotation 3 was cut for hay about J u n e 25, the stubble was immediately plowed, and the land fallowed for the remainder of the year. Rotations 4, 5, and 6 were regular four-year rotations with no fallow.
Cropping and Fertilization Plan
T h e experimental area was sweet clover fallow the year before the trial started. Recommended crop varieties and cultural practices were used. Each crop in each rotation was planted each year, except the alfalfa and mixed legume which were planted the previous year. Since the plots were 33 ft. wide and 45 ft. long, regular field machinery was used for all operations. T h e plots were randomized the first year and then followed the regular crop rotation sequence.
T h e soil tested medium in nitrogen, low in extractable phos- phorus, and high in exchangeable potassium. Each crop was indivi- dually fertilized annually. Rates and treatments are summarized in Table 1.
Table 1.—Fertilizer treatments used in sugar beet rotation studies, 1967-70.
Sugarbeets: 250 lb 0-46-0 /A. pre fall—broadcast 100 lb 6-42-0 /A. planting time-drill applied Wheat, barley, oats: 150 lb 25-25-0 /A.—drill applied Soybeans (22-inch rows): 100 lb/A. 25-25-0-row application Potatoes (40-inch rows): 300 lb /A. 5-20-20-row application
Results and Discussion
Average crop yields for the four-year period are given in Table 2.
Sugarbeet yields varied from a high of 18 tons in the black fallow rotation (No. 1) to a low of 16 tons per acre in the oat rotations (No. 6).
T h e yields of hard red spring wheat, malting barley, and oats were above average for the Crookston area but showed no consistent differ- ences between the fallow and the regular rotations.
Potato yields (shown in bushels) are slightly below average. Other crop yields were good and no yield differences between rotations appeared.
T h e organic matter added to the soil from the legume fallow
rotation (No. 2) averaged 2024 lbs per acre of dry matter. T h e alfalfa
248 JOURNAL OF THE A. S. S. B. T.
which was r e m o v e d from rotation 3 yielded 2140 lbs p e r acre a n d is r e p o r t e d as alfalfa hay in T a b l e 2.
T a b l e 2 . — A v e r a g e a c r e y i e l d s f o r a l l c r o p s i n s u g a r b e e t r o t a t i o n s t u d i e s a t C r o o k s t o n , M i n n e s o t a , 1 9 6 7 - 7 0 .
1.
2.
3.
4.
5.
6.
Beets 18.0 T Beets 17.5 T Beets 17.1 T Beets 17.0 T Beets 16.9T Beets 16.0 T
Wheat*
48.9 b u Wheat 46.8 bu Wheat 45.8 bu Potato***
266 bu Wheat 46.8 bu Wheat 46.4 bu
Barley 77.1 bu Barley 76.4 bu Barley 74.2 bu Wheat 46.0 bu Barley 75.1 bu Barlev 74.4 bu
Bl. fallow Mixed leg. fallow 2024 lb Alf. fallow**
2140 lb Barlev 76.9 bu Soybeans 27.5 bu Oats 102.7 bu
* All grain yields on p u r e seed basis
** 1st c r o p r e m o v e d , 15% moisture
*** No. 1 potato
S u g a r b e e t root yields, p e r c e n t s u g a r , a n d s u g a r yields for t h e six different rotations a r e given in T a b l e 3. T h e t h r e e rotations with fallow h a d the high root yields w h e n c o m p a r e d to those h a v i n g no fallow.
Root yields following oats (No. 6) w e r e significantly lower t h a n those following black a n d mixed l e g u m e fallow, b u t n o t from t h e o t h e r rotations.
T a b l e 3 . — S u g a r b e e t y i e l d , p e r c e n t s u g a r , a n d s u g a r p r o d u c t i o n w i t h t h e s i x r o t a t i o n s 1 9 6 7 - 7 0 .
R o t a t i o n 1. Black fallow 2. Mixed legume fallow 3. Alfalfa fallow 4. Barley 5. Soybeans 6. Oats
Y i e l d T / A 18.0a*
17.5a 1 7 . l a b 17.0ab 16.9ab 16.0 b
S u g a r
% 13.48 b 13.83ab 14.29ab 14.27ab 14.36a 14.80a
R e c o v e r a b l e s u g a r l b s / A
4 2 5 8 4 2 1 3 4317 4342 4311 4286
Root yields following black fallow (No. 1) were slightly h i g h e r t h a n those following m i x e d l e g u m e a n d alfalfa fallow, b u t t h e differences were n o t significant. T h i s seems to indicate t h a t soil m o i s t u r e in this a r e a is also i m p o r t a n t a n d fallowing t h e e n t i r e season is m o r e effective t h a n partial fallowing. T r i a l s have s h o w n t h a t by fallowing t h e e n t i r e
*Any two averages followed by the same letter do not differ at the 5% level according to Duncan's New Multiple R a n g e Test.
V O L . 17, N o . 3, A P R I L 1973 2 4 9 s e a s o n , 2 5 % , o r f o u r i n c h e s , o f t h e p r e c i p i t a t i o n t h a t falls d u r i n g t h e g r o w i n g s e a s o n o f t h e fallowing y e a r m a y b e s t o r e d a s available soil m o i s t u r e for f u t u r e c r o p u s e .
A r e a soils c o n t a i n 3 t o 5 % o r g a n i c m a t t e r , a n d all-season fallowing p r o b a b l y r e l e a s e s m o r e soil n i t r a t e - n i t r o g e n t h a n d o e s t h e p a r t i a l fal- l o w i n g o f r o t a t i o n s 2 a n d 3 . Also, soil f r o m t h e s e t h r e e fallow r o t a t i o n s s a m p l e d late i n t h e fall c o n t a i n e d a p p r o x i m a t e l y t h e s a m e a m o u n t o f n i t r a t e - n i t r o g e n in t h e 0 - 24 i n c h d e p t h .
R o o t yields o n t h e t h r e e n o n - f a l l o w r o t a t i o n s w e r e n o t significantly d i f f e r e n t , b u t b e e t s f o l l o w i n g o a t s ( N o . 6 ) w e r e t h e lowest. Since n o c o m m e r c i a l n i t r o g e n fertilizer w a s a d d e d d u r i n g t h e s t u d y , b e e t s o n t h e s e r o t a t i o n s s h o w e d signs o f n i t r o g e n deficiency.
Sugar Percentage
T h e k i n d a n d a m o u n t o f g r e e n m a n u r e a d d e d t o t h e soil g r e a t l y i n f l u e n c e s t h e s u g a r c o n t e n t o f b e e t s . N i t r o g e n o u s m a t e r i a l w h i c h r a p i d l y d e c a y s will p r o d u c e m o r e n i t r a t e - n i t r o g e n t h a n will c a r b o n a c e - o u s r e s i d u e s f r o m s m a l l g r a i n s . T h i s n i t r o g e n o u s m a t e r i a l p r o d u c e s m o r e a m i n o - n i t r o g e n a n d w i t h a g o o d s o d i u m s u p p l y t e n d s t o i n c r e a s e i m p u r i t i e s , r e s u l t i n g i n less s u g a r . E v e n t h o u g h b e e t s following o a t r o t a t i o n s w e r e e v i d e n t a l l y n i t r o g e n deficient, t h e y h a d t h e h i g h e s t p e r c e n t s u g a r w h e r e a s b e e t s f o l l o w i n g all t h r e e n o n - f a l l o w r o t a t i o n s w e r e lowest. S u g a r p e r c e n t a g e i n t h e b e e t s i n c r e a s e d f r o m a low o f 13.48 a n d 1 3 . 8 3 f o l l o w i n g black a n d m i x e d l e g u m e fallow, t o a h i g h o f 1 4 . 8 0 f o l l o w i n g o a t s , a significant d i f f e r e n c e . T h e r e w e r e n o significant d i f f e r e n c e s i n p e r c e n t s u g a r o f b e e t s g r o w n i n t h e t h r e e non-fallow r o t a t i o n s .
Recoverable Sugar
T h e g r o w e r i s p a i d o n r e c o v e r a b l e s u g a r a n d this i s o n e way t o c o m p a r e t h e r e l a t i v e v a l u e o f t h e s e r o t a t i o n s . N o n e o f t h e six r o t a t i o n s p r o d u c e d significantly m o r e s u g a r , b u t t h e black a n d m i x e d l e g u m e r o t a t i o n s w e r e t h e lowest. I t i s i n t e r e s t i n g t h a t b e e t s following black fallow o u t y i e l d e d b e e t s f o l l o w i n g o a t s b y t w o t o n s p e r a c r e , b u t t h e r e c o v e r a b l e s u g a r yields w e r e n e a r l y i d e n t i c a l .
Impurity Index
T h i s i n d e x i s o n e m e a s u r e o f t h e a m o u n t s o f i m p u r i t i e s p r e s e n t i n s u g a r b e e t s . F o u r f a c t o r s i n v o l v e d i n d e t e r m i n i n g this i n d e x a r e t h e a m o u n t s o f s o d i u m , p o t a s s i u m , a m i n o - N , a n d p e r c e n t s u g a r . I n g e n - e r a l , t h e h i g h e r t h e s o d i u m a n d a m i n o - n i t r o g e n c o n t e n t , t h e h i g h e r t h e i m p u r i t y i n d e x . T a b l e 4 gives t h e analysis o f s u g a r b e e t " b r i e " for t h e six r o t a t i o n s .
2 5 0 JOURNAL OF THE A. S. S. B. T.
Table 4.—Sugarbeet "brie": amounts of sodium, potassium, amino-N, and the impurity index, 1967-70.
1.
2.
3.
4.
5.
6.
Rotation with beets following Black fallow Mixed leg. fallow Alfalfa fallow Barley Soybeans Oats
N a 742ab*
794 a 663ab 633ab 643ab 538 b
K PPM***
1579bc 1652bc 1646bc 1534 c 1805 a 1682 b
Amino-N 454 a 470 a 438 a 386 ab 399 ab 294 b
Impurity**
Index 828 a 864 a 769 ab 711 ab 753 ab 639 b
* Any two averages followed by the same letter do not significantly differ at the 5% level according to Duncan's New Multiple Range Test.
** I m p u r i t y index =
*** Parts p e r million.
Beets following t h e t h r e e fallow r o t a t i o n s h a d s o m e w h a t h i g h e r s o d i u m c o n t e n t , a n d beets following t h e t h r e e non-fallow rotations t e n d e d to be lower. Beets following oats s h o w e d a significant r e d u c t i o n in this e l e m e n t as c o m p a r e d to beets following the m i x e d l e g u m e fallow. Potassium c o n t e n t varied. Beets following t h e t h r e e non-fallow rotations showed t h e greatest variation, a n d w e r e significantly differ- e n t from each o t h e r .
As e x p e c t e d , beets g r o w n on t h e t h r e e fallow r o t a t i o n s c o n t a i n e d m o r e a m i n o - n i t r o g e n a n d w e r e h i g h e r t h a n beets following oats. Beets f r o m t h e t h r e e non-fallow r o t a t i o n s w e r e lower in a m i n o - n i t r o g e n , reflecting t h e effect of c o n t i n u o u s cultivation.
Beets g r o w n o n t h e t h r e e fallow r o t a t i o n s h a d t h e highest a m o u n t o f s o d i u m a n d a m i n o - N a n d t h e lowest p e r c e n t o f s u g a r , r e s u l t i n g i n t h e highest i m p u r i t y i n d e x . T h e i m p u r i t y i n d e x o f beets following oats was significantly lower t h a n t h a t of beets g r o w n after m i x e d l e g u m e s a n d black fallow. T h e r e m o v a l o f t h e alfalfa c r o p l o w e r e d t h e a m o u n t of o r g a n i c m a t t e r a d d e d to t h e soil, r e s u l t i n g in a lower i m p u r i t y i n d e x for beets g r o w n following this c r o p .
Cost of Production
T o d e t e r m i n e cost o f p r o d u c t i o n , c u s t o m rates for N o r t h D a k o t a a n d M i n n e s o t a (6, 7) w e r e u s e d . An e x a m p l e of t h e p r o c e d u r e u s e d is s h o w n in T a b l e 5. A l a n d use cost of $ 2 0 p e r a n n u m p e r acre is an a v e r a g e figure for this a r e a . If a g r o w e r owns his l a n d , this cost w o u l d n o t be an "out-of-pocket" p a y m e n t , b u t for a r e n t e r it w o u l d b e . T a x e s a v e r a g e $ 5 p e r acre. E s t i m a t e d cost o f p r o d u c t i o n a n d s p e n d a b l e i n c o m e for s u g a r b e e t s (Table 5) shows t h a t if a g r o w e r o w n s his o w n land a n d carries his o w n risk ( i n s u r a n c e ) , $21 can be d e d u c t e d from e x p e n s e s a n d a d d e d to s p e n d a b l e i n c o m e . If a g r o w e r r e n t s l a n d , this would be a direct cost.
by A m e r i c a n Crystal Sugar
V O L . 1 7 , N o . 3 , A P R I L 1 9 7 3 2 5 1 Table 5.—Cost of production and spendable income per acre for sugarbeets grown
in rotation 1—1970.
Seed fertilizer $ 5.89
Chemical, risk 3.61 Land preparation 9.97 Labor (hoe & thin) 27.00 Harvesting 26.50
hauling 23.33 Land use 20.00 R. Tax 5.00
Total $121.30 Gross income $261.88 Production cost 121.30 Profit 140.58 Spendable income 2 1.00
Total spendable income $161.58
Spendable Income
Average net spendable income per acre for the six rotations is shown in Table 6. By adding the average spendable income per acre for the four crops in each rotation an average annual figure is obtained.
T h e four-year average net spendable income for beets varied from a low of $143 on the oat rotation to a high of $159 on the barley rotation (No. 4). Beets following the three fallow rotations produced about equal income, but were slightly lower than the three non-fallow rotations. Fallowing land for one year lowers net income which varies from $-16 for mixed legumes to $-6 for the rotation with alfalfa. On the latter, approximately one ton of alfalfa hay at $18 was annually pro- duced, compensating for part of the fallowing cost.
T a b l e 6 . — A v e r a g e total net s p e n d a b l e i n c o m e for s i x f o u r - y e a r sugar- beet rotations, 1967-70.
1. Beets
$145 2. Beets
$148 3. Beets
$150 4. Beets
$159 5. Beets
$149 6. Beets
$143
Wheat
$42 Wheat
$39 Wheat
$37 Potato
$232 Wheat
$39 Wheat
$38
Barley
$37 Barley
$36 Barley
$35 Wheat
$37 Barley
$36 Barley
$35
Bl. fallow
$-14 Mixed leg. fallow
$-16 Alf. fallow
$-6 Barley
$36 Soybeans
$34 Oats
$25
Total 4 crops
$210
$207
$216
$464
$258
$241
2 5 2 JOURNAL OF THE A. S. S. B. T.
T h e t h r e e non-fallow r o t a t i o n s p r o d u c e d m o r e net i n c o m e t h a n t h e fallow rotations over t h e four-year p e r i o d . Rotation N o . 4 (consist- ing of s u g a r b e e t s followed by potatoes, w h e a t , a n d barley) h a d t h e highest i n c o m e . T h e s u g a r b e e t c r o p p r o d u c e d t h e greatest d o l l a r r e t u r n with the exception of potatoes, b u t t h e most efficent use of t h e land d u r i n g t h e e n t i r e four-year p e r i o d m u s t b e c o n s i d e r e d .
S u m m a r y
T h e effect of six different f o u r - y e a r r o t a t i o n s on yield, p e r c e n t sugar, quality, a n d m o n e t a r y r e t u r n o f s u g a r b e e t s was s t u d i e d . Root yields following black a n d m i x e d l e g u m e fallow w e r e significantly h i g h e r t h a n those following oats. T h e r e w e r e n o o t h e r significant yield differences b e t w e e n t h e t h r e e fallow or b e t w e e n t h e t h r e e non-fallow rotations.
Beets following t h e t h r e e non-fallow r o t a t i o n s w e r e h i g h e r in s u g a r p e r c e n t a g e t h a n beets following t h e t h r e e fallow rotations.
Recoverable s u g a r yields from beets of all six r o t a t i o n s w e r e simi- lar, indicating that increased root yields on t h e t h r e e fallow rotations did not p r o d u c e h i g h e r r e c o v e r a b l e s u g a r yields.
S u g a r b e e t s g r o w n following fallow w e r e h i g h e r i n s o d i u m , a m i n o - n i t r o g e n a n d i m p u r i t y i n d e x e s t h a n those g r o w n o n land c r o p - p e d each year.
Results from this study indicate t h a t fallowing land did n o t in- crease t h e net i n c o m e from t h e s u g a r b e e t c r o p , o r t h e total f o u r - y e a r i n c o m e .
A c k n o w l e d g e m e n t
T h e a u t h o r wishes to e x p r e s s his a p p r e c i a t i o n to Mr. Ed Swift a n d his staff of t h e A m e r i c a n Crystal S u g a r C o m p a n y for d o i n g t h e s u g a r analysis, a n d to Dr. J o h n M. M a c G r e g o r , D e p a r t m e n t of Soil Science, University of Minnesota, for h e l p in p r e p a r i n g this p a p e r .
T h e r e s e a r c h r e p o r t e d in this p a p e r was partially s u p p o r t e d by t h e Red River Valley S u g a r b e e t G r o w e r s Association.
Literature Cited
(1) DUBETZ, S., G. C. RUSSELL, and K. W. H I L L . 1957. T h e effect of various preceding crops and sugarbeets. J. Am. Soc. Sugar Beet Technol. 9 (4) : 354-359.
(2) HILDE, DAVID J. 1969. Effects of rotation of sugarbeets in the Red River Valley. Crystal-ized Facts. American Crystal Sugar Co. Vol. 23, Spring No. 1.
VOL.. 17, N o . 3, A P R I L 1973 253 (3) ROBERTSON, D. W., R. E. DANIELSON, W. R. SCHMEHL, and R. S.
W H I T N E Y . 1967. T h e effect of alfalfa in a rotation on yield and quality of sugarbeets. Tech. XIV (5) : p. 405-411.
(4) T A N N E R , J. C. 1948. C r o p rotation practice in the Red River Valley.
Proc. Am. Soc. Sugar Beet Technol. p. 335-337.
(5) TANNER, J. C. 1954. Effects of rotation on sugarbeets in the Red River Valley, Proc. Am. Soc. Sugarbeet l e c h . Vol. 7, part 1, p. 86-89.
(6) NODLAND, T. R. and C. H. CUYKENDAEE. 1969. Custom rates for farm operations. Extension Pamphlet 134. Agricultural Extension Service, University of Minnesota, Minneapolis.
(7) VOSSEN, R. L. and C. J. HEETEMES. 1969. Custom farm work rates.
U. S. Dept. Agric. and No. Dak. State University, Fargo.