PROCEEDINGS
American Society of Sugar Cane Technologists
1950-57
Volume 5
January, 1957
F O R E W O R D
This is the fifth volume of p r o c e e d i n g s of the S o c i e t y which have been p u b l i s h e d s i n c e i t s founding in 193 8.
The f i r s t volume p u b l i s h e d i n 1941 i n c l u d e d p a p e r s p r e - s e n t e d during 1938, 1939 and 1940. M r . Walter Godchaux, J r . , the then S e c r e t a r y - T r e a s u r e r e d i t e d t h a t e d i t i o n .
The second volume published i n 1946 i n c l u d e d p a p e r s p r e - s e n t e d during the p e r i o d 1941-1945 i n c l u s i v e . D r . E. V. Abbott, Setrre - t a r y - T r e a s u r e r , e d i t e d that v o l u m e .
The t h i r d volume p u b l i s h e d i n 1953 included p a p e r s p r e - s e n t e d d u r i n g 1946-1950 i n c l u s i v e . The f o u r t h v o l u m e included p a p e r s p r e s e n t e d during 1951, 1952 and 1953. This the fifth volume i n c l u d e s p a p e r s p r e s e n t e d during 1954 and 1955. The l a s t t h r e e v o l u m e s i n c l u d - ing the p r e s e n t one w e r e e d i t e d by the w r i t e r .
ARTHUR G. K E L L E R
S E C R E T A R Y - T R E A S U R E R J a n u a r y 195 7
I N D E X A g r i c u l t u r a l S e c t i o n
P A G E Hot Air T r e a t m e n t of S u g a r c a n e in an Effort to C o n t r o l Stunting
D i s e a s e . Lloyd L. L a u d e n . . . 1
Why P i e c e W o r k ? R . J . L e B l a n c . 4 The S u g a r Cane B o r e r P r o b l e m in L o u i s i a n a T o d a y . A. L. Dugas . . 8
The I r r i g a t i o n of Sugar C a n e . R. J. L e B l a n c 18 A R e p o r t on the P r o g r e s s of the C o n t r o l of Stunting D i s e a s e .
Lloyd L. L a u d e n 22 F i e l d - M a d e S o i l C o n d i t i o n e r s - - H u m u s . F . E v a n s F a r w e l l . . . . 3 0
S u g a r c a n e P l a n t e r D e v e l o p m e n t i n L o u i s i a n a . R . M . R a m p . . . . 3 7 S t a t u s of S u g a r c a n e I n s e c t P r o b l e m s in L o u i s i a n a . Alvin L. Dugas 43 Study of R e s u l t s of S u g a r Cane I r r i g a t i o n C o s t s A g a i n s t Benefits
R e c e i v e d . F . A . G r a u g n a r d 5 3 M a n u f a c t u r i n g Section
The Use of E x t r a p o l for Reducing S u c r o s e L o s s e s in B a g a s s e .
L e s l i e R. B a c o n and J o s e p h V. O t r h a l e k . 53 Revolving Cane K n i v e s - - P a n e l D i s c u s s i o n . M. V. Y a r b r o u g h ,
M o d e r a t o r 74 P o l y e l e c t r o l y t e for S u g a r J u i c e C l a r i f i c a t i o n . J . H . T h i b a u t . . . . 8 0
V i s c o n F a b r i c as a F i l t e r M e d i a . C. W. S t e w a r t 83 M e c h a n i c a l Cane P l a n t i n g , M y E x p e r i e n c e i n L o u i s i a n a .
M. V. Y a r b r o u g h 85 The F a s F l o F i l t e r - - I t s Use i n S u g a r Refining and i n F i l t e r i n g the
Cloudy O l i v e r F i l t r a t e a t S u p r e m e Sugar R e f i n e r y .
J . M . F o r e t , J r . 9 8 E v a l u a t i o n of S u g a r Cane V a r i e t i e s - - S e a s o n 1954. W i l h e l m u s
Melis and C. W. S t e w a r t 103 A P r e l i m i n a r y R e p o r t o n Some F e r t i l i z e r E x p e r i m e n t s a t
R e s e r v e . L. G. J o y n e r . 115
HOT AIR T R E A T M E N T OF SUGARCANE IN AN E F F O R T TO CONTROL STUNTING DISEASE
B y Lloyd L . L a u d e n , A g r o n o m i s t and F i e l d R e p r e s e n t a t i v e , A m e r i c a n S u g a r c a n e L e a g u e and Leon Nugent, O p e r a t o r of Unit for A m e r i c a n S u g a r c a n e L e a g u e .
The r e p o r t , " T h e O c c u r r e n c e of a H i t h e r t o U n r e c o g n i z e d G r o w t h - R e t a r d i n g D i s e a s e of S u g a r c a n e in L o u i s i a n a " by D r . E. V. Abbott of the USDA S u g a r S t a t i o n , H o u m a , L a . , gave an account of a new d i s e a s e which w a s s p r e a d i n g v e r y r a p i d l y t h r o u g h o u t the cane fields of L o u i s i a n a . B e c a u s e of the c o n c e r n this r e p o r t c r e a t e d within the L o u i s i a n a s u g a r i n d u s t r y M r . Stephen C. M u n s o n , C h a i r m a n of the Contact C o m m i t t e e of the A m e r i c a n S u g a r Cane L e a g u e , appointed a c o m m i t t e e c o m p o s e d S . J . P . Chilton, Louis A r c e n e a u , E l l i o t t J o n e s and Lloyd L . Lauden to study the c o n t r o l of t h i s d i s e a s e .
T h i s c o m m i t t e e , after c o n s i d e r i n g the data f r o m A u s t r a l i a and the l i m i t e d a m o u n t of m a t e r i a l L o u i s i a n a State U n i v e r s i t y and the Houma S t a t i o n w e r e able t o o b t a i n i n the p e r i o d J a n u a r y t h r o u g h A u g u s t , 1953, r e c o m m e n d e d t h a t the L e a g u e s e t a s i d e a s u m not to e x c e e d $ 5 , 0 0 0 to be u s e d in the c o n s t r u c t i o n and o p e r a t i o n of a mobile hot a i r t r e a t i n g u n i t . This c o m m i t t e e d e c i d e d in favor of the hot a i r t r e a t m e n t o v e r the hot w a t e r t r e a t m e n t after g e r m i n a t i o n t e s t s i n August i n d i c a t e d t h a t b e t t e r r e s u l t s w e r e o b t a i n e d with h o t a i r t r e a t m e n t s of 129°F for 8 h o u r s than w i t h t r e a t m e n t s using hot w a t e r at e i t h e r 125°F for 1 1/2 h o u r s or 122°F for 2 h o u r s . The p l a n t a t i o n s c h o s e n by this c o m m i t t e e w e r e S e c o n d a r y I n c r e a s e S t a t i o n s a l r e a d y i n the cane i n c r e a s e p r o g r a m and w e l l d i s t r i b u t e d g e o g r a p h i c a l l y o v e r the s u g a r c a n e a r e a . The v a r i - e t i e s s e l e c t e d for t r e a t m e n t w e r e C P 3 6 - 1 0 5 , C P 4 4 - 1 0 1 , C P 3 4 - 1 2 0 , C P 3 6 - 1 3 , C P 4 3 - 4 7 , C P 2 9 - 3 2 0 , C P 4 4 - 1 5 5 , and C o - 2 9 0 .
After c o n s i d e r i n g the s e l e c t i o n of a unit, a La C r o s s t r a i l e r w i t h a 5 ton White p o w e r unit with a bed 9 feet wide and 26 feet long owned b y the L o u i s i a n a State A g r i c u l t u r a l E n g i n e e r i n g D e p a r t m e n t was u s e d . A c h a m b e r 9 feet w i d e , 26 feet long and 8 feet t a l l was b u i l t and s e c u r e d t o t h i s t r a i l e r b e d . T h i s c h a m b e r was c o n s t r u c t e d of 1/4 i n c h plywood and c o v e r e d with 55# r o l l roofing p a p e r . A D o h e r t y c r o p d r y e r supplied the h e a t . This d r y e r is p o w e r e d by a 20 h o r s e p o w e r V - 4 W i s c o n s i n engine with a p r o p e l l e r b l o w e r a s s e m b l e d d i r e c t l y to the c r a n k shaft. The c a p a c i t y of this d r y e r is 1 , 0 0 0 , 0 0 0 B T U of h e a t and an a i r flow of 3 0 , 000 C F M a g a i n s t a 3 / 4 " s t a t i c . This d r y e r was m o u n t e d o n the a p r o n o f the t r a i l e r . T e m p e r a t u r e s w e r e o b s e r v e d i n the cane with a T a g g - H e p p e n s t a l p o t e n t i o m e t e r . A r e c o r d i n g t h e r m o m - e t e r w a s u s e d t o i n d i c a t e the a i r t e m p e r a t u r e i n s i d e the c h a m b e r .
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The League engaged M r . Leon Nugent, a g r a d u a t e of L o u i s i a n a State U n i v e r s i t y , to o p e r a t e this unit.
An a t t e m p t to c o n t r o l the d i s t r i b u t i o n of h e a t when the c h a m b e r was solidly packed with cane failed even though the h e a t e n t e r e d the bottom and was e x h a u s t e d f r o m the top. A c e n t r a l ceiling duct c o n t a i n - ing 6 v a r i a b l e s i z e outlets was u l t i m a t e l y c o n s t r u c t e d and e x h a u s t p o r t s w e r e cut into the f l o o r i n g . R e m o v a b l e s h e l v e s w e r e then i n s t a l l e d t o allow good c i r c u l a t i o n of h e a t . L a r g e loading d o o r s w e r e c o n s t r u c t e d on one side of the c h a m b e r . All cane t r e a t e d was hand loaded into the c h a m b e r . A p p r o x i m a t e l y two h o u r s w e r e r e q u i r e d to load the a v e r a g e t r e a t m e n t of 4. 5 tons when four to s i x w o r k e r s w e r e u s e d . Unloading t i m e a v e r a g e d one and one-half h o u r s when the s a m e n u m b e r of w o r k - e r s w e r e u s e d .
S u c c e s s f u l o p e r a t i o n l a r g e l y depended upon the m a n n e r in which the cane was placed on the s h e l v e s inside the c h a m b e r . B e s t d i s t r i b u - tion of h e a t r e s u l t e d when the cane was s t a c k e d so as to l e a v e an a i r s p a c e between the s h e l v e s . It was n e c e s s a r y to p a c k the cane tightly a g a i n s t the walls both on the s i d e s and the e n d s . This d i s c o u r a g e d the t e n d e n c y of the a i r to channel the w a l l s . E x p e r i e n c e p r o v e d that a heavy l a y e r of cane on the floor of the c h a m b e r r e s u l t e d in b e t t e r d i s - t r i b u t i o n of h e a t . The f i r s t shelf in the r e a r end of the t r u c k p r o v e d u n n e c e s s a r y and was r e m o v e d . The cane h e r e was s t a c k e d tightly to about four inches of the second shelf.
T r i a l s placing t h e r m o c o u p l e s a t v a r i o u s p l a c e s within the c h a m - b e r i n d i c a t e d that the top of the c h a m b e r b e c a m e hot f i r s t and r e m a i n e d the h o t t e s t . The bottom or the floor l a y e r was next to b e c o m e hot and r e m a i n e d s o m e w h a t below the t e m p e r a t u r e of the top l a y e r . The c e n t e r l a y e r for the e n t i r e length of the c h a m b e r was l a s t to b e c o m e hot and was the m o s t difficult t o m a i n t a i n a t the r e q u i r e d t e m p e r a t u r e . F o r m o s t t r e a t m e n t s s e v e n t h e r m o c o u p l e s w e r e u s e d .
T h r e e t h e r m o c o u p l e s w e r e p l a c e d in t h r e e c a n e s in the top l a y e r , one in the f o r w a r d end, one in the c e n t e r s e c t i o n , and one in the r e a r of the c h a m b e r . T h r e e o t h e r t h e r m o c o u p l e s w e r e p l a c e d i n the c e n t e r l a y e r , one f o r w a r d , one c e n t e r , and one in the r e a r of the c h a m b e r . The o t h e r t h e r m o c o u p l e m e a s u r e d the t e m p e r a t u r e i m m e d i a t e l y below the a i r d u c t . T e m p e r a t u r e s w e r e o b s e r v e d and r e c o r d e d at 15 minute i n t e r v a l s in a l l t r e a t m e n t s .
I n s e v e r a l t r e a t m e n t s the d e s i r e d t e m p e r a t u r e i n one o r m o r e s e c t i o n s of the c h a m b e r was n e v e r r e a c h e d . This c a n e , h o w e v e r , h a s been planted and will b e o b s e r v e d . The a i r t e m p e r a t u r e i n s i d e the c h a m - b e r always r e a c h e d at l e a s t 1 2 9 ° F , and in s o m e i n s t a n c e s went f a r above 1 2 9 ° F .
T h r e e f a c t o r s which affected the t i m e r e q u i r e d for the c a n e s to r e a c h 129°F w e r e the s i z e of the c a n e , the amount of l e a v e s on the c a n e , and the c l i m a t i c c o n d i t i o n s . C l e a n , s m a l l b a r r e l e d c a n e s t r e a t e d o n w a r m sunny days r e s u l t e d i n good t r e a t m e n t s . Cloudy, cold, o r r a i n y days w e r e not conducive to good t r e a t m e n t s r e g a r d l e s s of the s i z e of
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the c a n e .
Unfortunately t h i s unit w a s not c o m p l e t e d and r e a d y for u s e until n e a r the beginning of g r i n d i n g and at t h a t t i m e m a n y p l a c e s o r i g i n a l l y s e l e c t e d w e r e e x t r e m e l y b u s y with h a r v e s t i n g o p e r a t i o n s . The s t r i k e a l s o p r e v e n t e d the t r e a t m e n t o f cane a t s e v e r a l p l a c e s . B e c a u s e the W e s t e r n a r e a was not affected b y the s t r i k e m o r e cane was t r e a t e d t h e r e . In spite of a l a t e s t a r t and the s t r i k e d i f f i c u l t i e s , a p p r o x i m a t e l y 131 tons of cane w e r e t r e a t e d .
Below a r e the p l a c e s v i s i t e d and the v a r i e t i e s t e s t e d .
V a r i e t i e s T r e a t e d
Plantations 34-120 36-13 36-155 44-101 44-155 Co290 Tons
Smithfield* 10. 0 10.0 St. J a m e s C o - o p . 4 . 0 4 . 5 Glenwood 4. 5 Clovelly F a r m s 9. 0
Oaklawn 4 . 0 4 . 5 4. 5 4. 5 4. 5 O r a n g e G r o v e ( I b e r i a ) 11.0 2 0 . 0 2 . 0
L a n d r y ( I b e r i a ) 5.0 E n t e r p r i s e P l a n t a t i o n 6 . 0 9 , 0
Godchaux ( R a c e l a n d ) 13. 5
T o t a l s 9 . 0 4 . 0 3 5 . 5 7 1 . 0 6 . 5 4 . 5
* Cane t r e a t e d i n s o l i d m a s s , s o m e s e c t i o n s t e m p e r a t u r e s r e a c h e d 1 8 0 ° F ; o t h e r s e c t i o n s t e r m p e r a t u r e s r e a c h e d only 7 9 ° F . T h i s cane is c o n s i d e r e d of no v a l u e .
B e t t e r d i s t r i b u t i o n of h e a t could be b r o u g h t about with t h i s unit b y i n s u l a t i n g the c h a m b e r . T h e r e i s a l s o the p o s s i b i l i t y that the i n - s t a l l a t i o n of d e f l e c t o r s at the openings in the ducts could a s s i s t in b e t - t e r d i s t r i b u t i o n of h e a t .
T r e a t e d c a n e s have been dug up for o b s e r v a t i o n to d e t e r m i n e the e x t e n t g e r m i n a t i o n w a s i m p a i r e d . The e y e s o n m o s t m a t e r i a l o b - s e r v e d s e e m e d to be sound and s h o o t s w e r e beginning to a p p e a r by J a n u a r y 5, 1954. Most of the t r e a t e d m a t e r i a l was planted r a t h e r l a t e , and, i n s o m e c a s e s , i n e x t r e m e l y d r y s o i l .
I t i s too e a r l y t o d r a w any c o n c l u s i o n s f r o m t h i s e x p e r i m e n t a t this t i m e . I t i s hoped, h o w e v e r , that the m a t e r i a l t r e a t e d w i l l c o m e up to a good s t a n d and be f r e e of the Stunting D i s e a s e .
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WHY PIECE WORK?
By R. J. L e B l a n c - - G o d c h a u x S u g a r s , I n c . , Raceland, L o u i s i a n a T h e r e has been quite a bit of i n t e r e s t evidenced lately r e g a r d - ing the piece r a t e s y s t e m we have e s t a b l i s h e d in connection with our field w o r k e r s and at the r e q u e s t of M r . R i c h a r d M c C a r t h y , J r . , C h a i r - man of the Society's A g r i c u l t u r a l Section, I have p r e p a r e d a p a p e r on this subject to be p r e s e n t e d to you today.
This s y s t e m was f i r s t instituted in our field operations two y e a r s ago. . d u r i n g the planting of the 1952 c r o p . We a l s o c a r r i e d it over into our 1952 h a r v e s t i n g o p e r a t i o n s on a modified b a s i s in connection with c r o s s i n g cane and salvaging or cleaning behind the h a r v e s t i n g m a c h i n e s . It was the r e s u l t of studies we made in an effort to e n c o u r a g e labor to r e m a i n on our f a r m s , for as you all know, during the p a s t s e v e r a l y e a r s field labor has been moving away from f a r m s in i n c r e a s i n g n u m b e r s into local i n d u s t r i e s .
We felt that the e s t a b l i s h m e n t of s u c h a s y s t e m would not only p r o v i d e an incentive for our l a b o r e r s to a c c o m p l i s h m o r e . , and be c o m - p e n s a t e d a c c o r d i n g l y . . during t h e i r nine hour d a y ' s w o r k , but at the s a m e time it would a l s o allow us to complete our r e q u i r e d work s c h e d - ules with the fewer people living on the f a r m .
The r e s u l t s of the piece work r a t e s on planting cane and the modified piece work r a t e s in our h a r v e s t i n g o p e r a t i o n s for the 1952 c r o p a p p e a r e d to us to be s u c c e s s f u l enough so that for the 1953 s e a s o n we e s t a b l i s h e d p i e c e w o r k r a t e s for all of our planting and h a r v e s t i n g o p e r a t i o n s .
It should be c l e a r l y understood that "piece w o r k " is quite dif- f e r e n t from " t a s k w o r k " , which l a t t e r s y s t e m i s a l s o used e x t e n s i v e l y in s u g a r cane o p e r a t i o n s . On a "piece w o r k " b a s i s , a w o r k e r m u s t put in a full d a y ' s work and if he a c c o m p l i s h e s m o r e than the e s t a b - lished r e q u i r e m e n t s for a d a y ' s w o r k , he is paid e x t r a wages above his r e g u l a r d a y ' s pay for the additional amount of work a c c o m p l i s h e d during that work day. Under t a s k w o r k r a t e s , a w o r k e r is given a c e r t a i n amount of w o r k to p e r f o r m , after which his d a y ' s w o r k is done except that the t a s k should be s u c h that the w o r k e r m u s t a c c o m p l i s h it at l e a s t within the w o r k day.
In our e x p e r i e n c e , we found during the p a s t two y e a r s that the number of w o r k e r s r e q u i r e d when piece work is used is c o n s i d e r a b l y l e s s than the labor r e q u i r e m e n t s for a day or "task w o r k " b a s i s . B e - cause our l a b o r e r s work nine hours a day and that under our piece work s y s t e m they a r e given an incentive by which they can e a r n e x t r a
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pay if m o r e than a r e g u l a r d a y ' s w o r k is a c c o m p l i s h e d , we have b e e n able to r e d u c e our l a b o r r e q u i r e m e n t s both for planting and h a r v e s t - ing o p e r a t i o n s . I might add that we have found a v e r y f a v o r a b l e a t t i - tude e x i s t i n g among our l a b o r e r s who have been getting h i g h e r wages c o m m e n s u r a t e with t h e i r p r o d u c t i o n o r p e r f o r m a n c e r e c o r d . W e a r e planning t o use this s a m e s y s t e m again this y e a r , i m p r o v i n g i t w h e r e e v e r p o s s i b l e .
In o p e r a t i n g our planting s c h e d u l e on the piece w o r k b a s i s , the key to the a m o u n t of planting done by any s e t or c r e w is the a c t u a l n u m - b e r of m e n r i d i n g the c a r t s for the p u r p o s e of throwing out the cane and t h o s e who fix the cane in the r o w . P a s t e x p e r i e n c e shows that one a c r e p l a n t e d p e r day p e r m a n in this key g r o u p is a r e a s o n a b l e r a t e and this has been e s t a b l i s h e d as the p i e c e w o r k b a s i s . Following is a hypothet- i c a l c a s e showing the a c t u a l o p e r a t i o n of this piece r a t e b a s e d on a c o m - bined g r o u p o p e r a t i o n c o n s i s t i n g of s e v e r a l p l a n t a t i o n s , w h e r e 800 to 1,000 a c r e s of cane planting a r e involved and w h e r e five s e t s or c r e w s planting two r o w s e a c h a r e u s e d . T h e s e c a l c u l a t i o n s a r e figured o n e a c h s e t or c r e w planting s i x a c r e s p e r nine hour day, or a t o t a l of t h i r t y a c r e s p e r d a y .
In this s c h e d u l e all of the w o r k e r s would be p a i d the e x t r a pay- m e n t a c c o r d i n g to the n u m b e r of a c r e s e a c h p a r t i c u l a r s e t p l a n t e d a- bove i t s r e q u i r e m e n t s .
Our e x p e r i e n c e so far has shown that under the incentive or p i e c e r a t e s y s t e m our w o r k e r s can and have e a r n e d a n y w h e r e from 25% to 75% m o r e than they would o t h e r w i s e n o r m a l l y r e c e i v e for a r e g u l a r nine h o u r d a y ' s planting w o r k , L i k e w i s e our w o r k e r s a l s o found that d u r i n g our h a r v e s t i n g o p e r a t i o n s under the p i e c e w o r k or i n c e n t i v e s y s t e m they could e a r n m o r e than b y the p r e v i o u s day method and w e , in t u r n , found t h a t we could h a r v e s t our c r o p with little or no m o r e l a b o r than r e q u i r e d d u r i n g our r e g u l a r cultivating s e a s o n . This e l i m i n a t e d tLe n e e d of h i r i n g e x t r a o u t s i d e h e l p , as we had b e e n doing i n the p a s t , plus having t o a s s u m e a l l the p r o b l e m s involving t r a n s - p o r t a t i o n , lodging and so forth that go with the e m p l o y m e n t of s u c h w o r k e r s .
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$235.07 100.00 $7.84
6
I n i n s t i t u t i n g t h e p i e c e r a t e s y s t e m o n a p e r a c r e b a s i s f o r a l l w o r k e r s i n t h e c u t t i n g o p e r a t i o n , w e s t u d i e d p a s t p e r f o r m a n c e r e c o r d s a n d u s e d t h e a v e r a g e d a i l y p e r f o r m a n c e a s t h e c u t t i n g r e q u i r e m e n t i n e s t a b l i s h i n g p i e c e r a t e s f o r t h i s o p e r a t i o n . T h e s e p i e c e r a t e s a r e :
O p e r a t i o n P i e c e R a t e B a s i s H a r v e s t e r O p e r a t o r $ 1 . 0 0 p e r s q . a c r e H a r v e s t e r B l a d e m a n . 7 5 p e r s q . a c r e S a l v a g i n g ) 3 . 0 0 p e r s q . a c r e
) a f t e r h a r v e s t e r s
C r o s s i n g ) . 2 0 p e r l i n e a l a c r e C u t t i n g e n d s . 5 0 p e r l i n e a l a c r e O n l o a d i n g a n d h a u l i n g o p e r a t i o n s , w e f o u n d t h a t t h e c r e w s c o v e r e d a n a v e r a g e o f t h i r t e e n a c r e s p e r n i n e h o u r d a y ; s o , e x t r a b o n u s p a y w a s p a i d t o t h e s e w o r k e r s a f t e r t h e y h a d c o v e r e d t h i r t e e n a c r e s a d a y . T h i s e x t r a p a y w a s :
L o a d e r a n d d e r r i c k o p e r a t o r s $ . 0 6 p e r a c r e b o n u s T r a c t o r o p e r a t o r s . 0 5 p e r a c r e b o n u s A l l o t h e r s i n v o l v e d . 0 4 p e r a c r e b o n u s
A s i n t h e c a s e o f p l a n t i n g o p e r a t i o n s , w e a l s o i n t e n d t o c o n t i n u e t h e p i e c e w o r k s y s t e m d u r i n g t h i s c o m i n g y e a r ' s h a r v e s t i n g o p e r a t i o n s a n d t o i m p r o v e i t , w h e r e v e r p o s s i b l e .
I b e l i e v e t h i s a b o u t c o v e r s t h e s u b j e c t , b u t i f a n y o f y o u g e n t l e - m e n h a v e a n y q u e s t i o n s t o a s k , I w i l l g l a d l y a t t e m p t t o a n s w e r t h e m .
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T H E S U G A R C A N E B O R E R P R O B L E M IN LOUISIANA T O D A Y By A. L. Dugas, E n t o m o l o g i s t - - L o u i s i a n a A g r i c u l t u r a l Experiment Station.
Because of the p r e s e n t i n t e r e s t in the sugarcane b o r e r as a s e r i o u s problem throughout the cane growing a r e a of Louisiana, t h e r e appears to be need for a frank discussion of the p r a c t i c a l aspects of the status of the insect and the available control m e a s u r e s . No attempt will be made to p r e s e n t the r e s u l t s of the many y e a r s of technical r e - s e a r c h by the Louisiana and F e d e r a l Stations except in the application of these findings to a better understanding of the problem from a more p r a c t i c a l point of view.
P e r h a p s , one of the limiting factors in the failure of the cane industry to r e a l i z e even more p r o g r e s s in b o r e r control than has been m a d e , is the lack of appreciation on the p a r t of some of the g r o w e r s and farm organizations of the importance of the problem and the com- plications that a r e involved. An attempt is made in this paper to dis- cuss as briefly as possible some of the m o r e pertinent phases which might lead to a better understanding of the g e n e r a l nature of the prob- l e m .
PRESENT AND PROSPECTIVE STATUS OF THE BORER PROBLEM The r e l a t i v e importance of the insect and the corresponding amount of money that should be spent on its control depends upon the extent and level of infestation. This v a r i e s of c o u r s e from y e a r to year not only over the cane belt as a whole but on individual f a r m s . The contribution of the e x p e r i m e n t stations r e l a t i v e to the knowledge of l o s s e s , p r e s e n t s t a t u s , and prospective outlook, is in the form of two s u r v e y s ; one a fall survey of b o r e r l o s s e s during harvesting; the o t h e r , an overwintering and mortality s u r v e y in e a r l y spring to de- t e r m i n e winter c a r r y o v e r of b o r e r s .
Since it has been found that there is a close relationship be- tween the b o r e r population that successfully overwinters and the ex- tent of l o s s e s at h a r v e s t - t i m e , it is possible most y e a r s to p r e d i c t with almost unbelievable a c c u r a c y what the b o r e r infestation will be like the coming s e a s o n . This information has been of i m m e n s e value to the g r o w e r s in making plans and p r e p a r a t i o n s for their control p r o - g r a m . All g r o w e r s a r e urged to take advantage of this worthwhile data furnished by these s u r v e y s .
Now, what has the surveys indicated the l a s t two y e a r s , and what is the p r o s p e c t s and status of the b o r e r at the p r e s e n t t i m e ? The
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h a r v e s t t i m e s u r v e y d a t a showed t h a t t h e r e w e r e e x t e n s i v e l o s s e s i n 1952 and ' 5 3 , which followed c a r r y o v e r s of l a r g e populations of b o r e r s e a c h y e a r . Again this y e a r , the o v e r w i n t e r i n g s u r v e y r e v e a l e d a heavy c a r r y - over and the f i r s t g e n e r a t i o n i n f e s t a t i o n at the p r e s e n t t i m e is c e r t a i n l y i n d i c a t i v e of t h i s .
The g e n e r a l s t a t u s of the s u g a r c a n e b o r e r as a p e s t of cane and c o r n has changed c o n s i d e r a b l y in the p a s t two or t h r e e y e a r s . The in- s e c t o c c u r r e d p r e v i o u s l y i n l o c a l i z e d a r e a s i n the cane growing a r e a and for the m o s t p a r t on the m o r e sandy front lands of the l a r g e r plan - t a t i o n s . The p r e d i c t i o n that the b o r e r could v e r y well b e c o m e a m o r e s e r i o u s p e s t b e c a u s e of e x i s t i n g conditions has unfortunately been r e a l - i z e d . The l a r g e a c r e a g e being planted t o the v e r y s u s c e p t i b l e v a r i e t i e s , C . P . 4 4 / 1 0 1 , C. P. 4 4 / 1 5 5 and C. P. 3 6 / 1 3 and the d i s a p p e a r a n c e of C . P . 3 4 / 1 2 0 , the e x t r e m e l y r e s i s t a n t v a r i e t y , t o g e t h e r with the o c c u r - r e n c e of t h r e e c o n s e c u t i v e m i l d w i n t e r s favoring s u c c e s s f u l o v e r w i n t e r - ing of the b o r e r a r e the p r i n c i p a l c o n t r i b u t i n g f a c t o r s to the p r e s e n t s i t u a t i o n . S u c c e s s f u l o v e r w i n t e r i n g of l a r g e populations of b o r e r s is a l s o a t t r i b u t e d to the e x t e n s i v e a m o u n t of cane p i e c e s and s t a l k s that a r e left in the field d u r i n g h a r v e s t u n d e r the p r e s e n t day s p e e d y , m e c h - a n i z e d s y s t e m .
The b o r e r is now a p r o b l e m throughout the cane b e l t , on s m a l l f a r m s as w e l l as on l a r g e o n e s , on sandy soils and b l a c k s o i l s a l i k e , even in s u c h a r e a s as t h a t of B u n k i e - C h e n e y v i l i e , B r o u s s a r d - Y o u n g s - v i l l e , New R o a d s , St. J a m e s and p a r t s of Bayou L a f o u r c h e , w h e r e the b o r e r was unknown p r e v i o u s l y . An i d e a of the i n c r e a s e in scope of its s e r i o u s n e s s is r e v e a l e d by the fact that p r e v i o u s l y it was thought to be a s e r i o u s p r o b l e m on about 3 0, 000 a c r e s of c a n e , but with the i n c r e a s e and s p r e a d which h a s t a k e n p l a c e the p a s t t h r e e y e a r s and the e x t r e m e l y h e a v y f i r s t g e n e r a t i o n i n f e s t a t i o n in the fields at the p r e s e n t t i m e , as m u c h as 200, 000 a c r e s or m o r e m a y be affected s e r i o u s l y this y e a r .
G e n e r a l l y speaking for the cane belt as a whole, s m a l l f a r m e r s a r e now suffering h e a v i e r l o s s e s p e r a c r e than the l a r g e o n e s , since they no longer e s c a p e the p r o b l e m and have failed to a c c e p t a c o n t r o l p r o g r a m .
D E V E L O P M E N T AND HABITS OF THE BORER
Some of you may wonder why e v e r so often you a r e exposed to s o m e b a s i c i n f o r m a t i o n r e g a r d i n g the life h i s t o r y and habits of the b o r e r . The r e a s o n is s i m p l e , for the whole c o n t r o l p r o g r a m is b a s e d upon c e r - tain d e v e l o p m e n t s and h a b i t s of the i n s e c t . Such i n f o r m a t i o n as the dif- f e r e n t s t a g e s in the life of the i n s e c t , the habits of the l a r v a and the adult m o t h , the n u m b e r of g e n e r a t i o n s e a c h y e a r , when and w h e r e it h i b e r n a t e s , and m u c h m o r e is e s s e n t i a l for one to r e a l l y u n d e r s t a n d and s u c c e s s f u l l y c o n t r o l the p e s t .
T h e r e a r e four s t a g e s in the life cycle of the b o r e r ; n a m e l y , the egg, l a r v a or b o r e r , pupa or r e s t i n g s t a g e and the adult moth. In g e n e r a l ,
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t h i s t e l l s u s w h a t t o l o o k f o r i n f o l l o w i n g t h e d e v e l o p m e n t o f t h e b o r e r t h r o u g h t h e s e a s o n . T h e f a c t t h a t t h e a d u l t i s a m o t h m e a n s t h a t t h e i n f e s t a t i o n c a n n o t b e e x p e c t e d t o s t a y p u t i n a f i e l d . I t a l s o a n s w e r s t h e q u e s t i o n a s t o w h y f i e l d s w i t h n o d e a d - h e a r t s m a y b e c o m e h e a v i l y i n f e s t e d b y t h e s e c o n d g e n e r a t i o n . I t i s t h e i n f l u x o f m o t h s i n t o m o r e a t t r a c t i v e c a n e .
I n L o u i s i a n a , d u r i n g l a t e f a l l a n d w i n t e r , N o v e m b e r t o M a r c h , t h e b o r e r i s h i b e r n a t i n g a s a f u l l g r o w n l a r v a e i n c a n e p i e c e s , s t u n t e d s t a l k s , s u c k e r s a n d w h o l e s t a l k s l e f t i n t h e f i e l d s d u r i n g h a r v e s t , i n s t u b b l e s , i n s u m m e r - p l a n t e d c a n e , a n d i n s o m e y e a r s i n s h o o t s g r o w - i n g f r o m e a r l y h a r v e s t e d c a n e . S m a l l n u m b e r s s o m e t i m e o v e r w i n t e r i n J o h n s o n g r a s s o r o t h e r l a r g e s t e m g r a s s e s . U n d e r n o r m a l t e m p e r a - t u r e c o n d i t i o n s , o v e r w i n t e r e d b o r e r s b e g i n t o p u p a t e i n l a t e F e b r u a r y a n d M a r c h , a n d m o t h s e m e r g e i n l a r g e n u m b e r s a b o u t t h e f i r s t w e e k o f A p r i l . T h i s k n o w l e d g e s u g g e s t s the l i k e h o o d o f a p p l y i n g c u l t u r a l p r a c - t i c e s t o r e d u c e t h e n u m b e r o f b o r e r s s u r v i v i n g t h e w i n t e r t o t h e l o w e s t p o s s i b l e l e v e l .
S t a r t i n g a b o u t t h e f i r s t w e e k o f A p r i l , e g g s a r e l a i d i n m a s s e s o f a b o u t t w e n t y e a c h o n t h e s m a l l c a n e a n d s o m e t i m e s o n e a r l y p l a n t e d c o r n t o b e g i n t h e f i r s t g e n e r a t i o n . T h e e g g s h a t c h i n f o u r t o e i g h t d a y s a n d t h e y o u n g b o r e r s w o r k t h e i r w a y d o w n i n t o t h e b u d o r c e n t r a l w h o r l o f t h e p l a n t , w h e r e t h e y f e e d f r o m o n e t o t h r e e w e e k s d e p e n d i n g u p o n t e m p e r a t u r e s . T h i s f e e d i n g i n t h e b u d c a u s e s l e a f s i g n s o r l e a f p e r - f o r a t i o n s , w h i c h a r e t h e f i r s t i n d i c a t i o n s o f b o r e r i n f e s t a t i o n i n t h e s p r i n g . T h e l a r v a e t h e n m o v e d o w n b e h i n d t h e l e a f s h e a t h s a n d t h e r e f e e d f o r a w e e k o r l o n g e r , t h e l e n g t h o f t h i s p e r i o d d e p e n d i n g u p o n t h e f a v o r a b l e n e s s o f t h e w e a t h e r . T h e t i m e e l a p s i n g f r o m h a t c h i n g o f t h e l a r v a u n t i l i t g a i n s e n t r a n c e i n t o t h e p l a n t i s g e n e r a l l y m o r e t h a n t w o w e e k s . T h i s a l l o w s s u f f i c i e n t t i m e f o r d e t e r m i n i n g t h e f i e l d s t h a t w i l l n e e d d u s t i n g a n d f o r m a k i n g a r r a n g e m e n t s f o r a p p l y i n g t h e f i r s t a p p l i - c a t i o n o f p o i s o n f o r f i r s t g e n e r a t i o n c o n t r o l . F i r s t g e n e r a t i o n e g g l a y - i n g c o n t i n u e s f o r a b o u t t w o o r t h r e e w e e k s a f t e r g e n e r a l h a t c h i n g o c c u r s , c o n s q u e n t l y f o u r w e e k l y a p p l i c a t i o n s o f p o i s o n a r e n o r m a l l y s u f f i c i e n t t o c o v e r t h e p e r i o d .
I n l a t e M a y , d e a d h e a r t s , t h e d y i n g o f t h e c e n t r a l w h o r l o f t h e p l a n t s , r e s u l t i n g f r o m f e e d i n g o f t h e f i r s t g e n e r a t i o n , b e g i n t o a p p e a r . T h e s e b o r e r s r e a c h m a t u r i t y t o w a r d t h e e n d o f M a y a n d t h e m o t h s e - m e r g e a n d b e g i n l a y i n g e g g s f o r t h e s e c o n d g e n e r a t i o n a b o u t t h e f i r s t w e e k o f J u n e . C o n s e q u e n t l y , t h i s i s t h e t i m e t o r e l e a s e t h e e g g p a r a - s i t e s , T r i c h o g r a m m a . T h e r e i s u s u a l l y a p e r i o d o f a b o u t t h r e e w e e k s t o a m o n t h b e t w e e n t h e a p p e a r a n c e o f t h e l a s t e g g s o f t h e f i r s t g e n e r a - t i o n a n d t h e f i r s t e g g s o f t h e s e c o n d g e n e r a t i o n . T h e r e f o r e , t h e r e i s n o n e e d o f i n s e c t i c i d a l a p p l i c a t i o n s f r o m a b o u t M a y 1 0 u n t i l J u n e 1 5 t o 2 0 .
A g e n e r a l h a t c h i n g o f s e c o n d g e n e r a t i o n l a r v a o c c u r s a b o u t t h e 1 5 t o 2 0 t h o f J u n e . T h i s i s t h e c l u e f o r s t a r t i n g i n s e c t i c i d a l a p p l i c a - t i o n s f o r s e c o n d g e n e r a t i o n c o n t r o l . B y s o d o i n g , f o u r w e e k l y a p p l i c a t i o n s
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o f i n s e c t i c i d e s t a k e c a r e o f t h e s e c o n d g e n e r a t i o n i n m o s t f i e l d s . T h e n e w l y h a t c h e d s e c o n d - g e n e r a t i o n b o r e r s d i f f e r i n h a b i t f r o m t h o s e o f t h e f i r s t i n t h a t t h e y v e r y s e l d o m d o a n y f e e d i n g i n t h e b u d o f t h e p l a n t b u t m o v e d i r e c t l y d o w n t h e s t a l k t o t h e i n s i d e o f t h e l e a f s h e a t h s . A l - t h o u g h t h e r e m a y b e s o m e l e a f f e e d i n g , e s p e c i a l l y i n h e a v i l y i n f e s t e d f i e l d s o r i n s t u n t e d c a n e , t r u e l e a f s i g n s a r e g e n e r a l l y n o t c o m m o n e n o u g h t o b e u s e d a s a c r i t e r i o n f o r s e l e c t i n g f i e l d s f o r s e c o n d g e n e r a - t i o n d u s t i n g . I n f i e l d s w h e r e t h e r e w a s l i t t l e o r n o f i r s t g e n e r a t i o n i n - f e s t a t i o n , t h e r e f o r e n o d e a d h e a r t s , t h e o n l y a v a i l a b l e c r i t e r i o n i s l e a f s h e a t h f e e d i n g . I n f i e l d s t h a t h a d m e d i u m t o h e a v y f i r s t g e n e r a t i o n i n - f e s t a t i o n s t h e n u m b e r o f d e a d h e a r t s p e r a c r e i s a g o o d m e a s u r e .
I t i s u s u a l l y a b o u t t h e f i r s t w e e k o f A u g u s t w h e n a g e n e r a l h a t c h - i n g o f t h i r d g e n e r a t i o n e g g s o c c u r s . T h i s g e n e r a t i o n i s n o t s o c l e a r l y d e - f i n e d a s t h e f i r s t o r s e c o n d , b u t i n m o s t f i e l d s , t h e r e i s a s h o r t p e r i o d o f t i m e b e t w e e n t h e s e c o n d a n d t h i r d d u r i n g w h i c h l i t t l e o r n o e g g s a r e l a i d . T h e r e i s o f c o u r s e m o r e o v e r l a p p i n g o f t h e t h i r d , f o u r t h a n d f i f t h g e n e r a t i o n s o f b o r e r s . T h e f a c t t h a t t h i r d g e n e r a t i o n b o r e r s o f t e n c o n c e n t r a t e i n f i e l d s o f s t u n t e d c a n e i n w h i c h j o i n t s a r e j u s t b e g i n n i n g t o f o r m a n d t h e r e d o t h e s a m e t y p e o f i n j u r y a s t h e s e c o n d g e n e r a t i o n d o e s i n n o r m a l g r o w i n g c a n e , s u g g e s t s t h e n e e d o f c o n t i n u i n g t h e d u s t - i n g t o i n c l u d e t h i r d g e n e r a t i o n c o n t r o l i n s u c h f i e l d s ,
T h i s g i v e s s o m e i n d i c a t i o n o f h o w c o n t r o l m e a s u r e s a r e t i e d i n w i t h t h e d e v e l o p m e n t , l i f e c y c l e , a n d h a b i t s o f t h e b o r e r .
T Y P E O F D A M A G E A N D L O S S E S C A U S E D B Y T H E B O R E R S o m a n y g r o w e r s f a i l t o r e a l i z e t h e t r e m e n d o u s l o s s e s w h i c h a r e d i r e c t l y a t t r i b u t a b l e t o b o r e r d a m a g e . T h e h e a v i e s t i n f e s t a t i o n s f o l l o w t h e m i l d w i n t e r s w h i c h a r e a l s o c o n d u c i v e t o g o o d c a n e c r o p s b y a c c o u n t i n g f o r s u p e r i o r s t a n d s , l o n g g r o w i n g p e r i o d s , a n d b e t t e r m a t u r i t y . I n s u c h y e a r s , m o s t g r o w e r s m a k e a b e t t e r t h a n a v e r a g e c r o p a n d c o n s e q u e n t l y h a v e a t e n d e n c y t o d i s r e g a r d t h e h e a v y l o s s e s f r o m b o r e r s . W i t h l i t t l e o r n o b o r e r d a m a g e i n a n e x c e l l e n t c a n e g r o w - i n g y e a r l i k e ' 5 3 , t h e y i e l d s w o u l d h a v e b e e n b e y o n d t h e i m a g i n a t i o n o f m o s t o f u s .
F e e d i n g b y t h e b o r e r c a u s e s p l a n t d a m a g e i n m a n y w a y s a n d l o s s e s a r e i n r e l a t i o n t o t h e l e v e l o f i n f e s t a t i o n . A l t h o u g h s o m e o f t h e f e e d i n g s i g n s d o n o t p r o d u c e l o s s e s , t h e y a r e u s e d a s a n i n d e x f o r m e a s u r i n g b o r e r i n f e s t a t i o n s .
1 . L e a f f e e d i n g - T h e l e a f s i g n s o r l e a f p e r f o r a t i o n s r e s u l t i n g f r o m f e e d i n g o f t h e y o u n g b o r e r i n t h e b u d o f t h e p l a n t a c t u a l l y a c c o u n t f o r n o h a r m , b u t a r e a m e a n s f o r d e t e r m i n i n g t h e l e v e l o f t h e f i r s t g e n e r a t i o n i n f e s t a t i o n a t i t s b e g i n n i n g .
2 . D e a d h e a r t s - T h e d e a d h e a r t s c a u s e d b y f i r s t g e n e r a t i o n b o r e r a t t a c h a r e t h e f i r s t s i g n s o f p l a n t i n j u r y , b u t t h e s e a r e n o t i m - p o r t a n t l o s s e s , s i n c e t h e r e a r e n o j o i n t s o n t h e p l a n t s a t t h a t t i m e , a n d s u c k e r s s p r o u t o u t t o r e p l a c e t h e d e a d h e a r t p l a n t s . T h e n u m b e r o f d e a d -
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h e a r t s i s a m e a n s o f m e a s u r i n g t h e f i r s t g e n e r a t i o n i n f e s t a t i o n n e a r i t s c o m p l e t i o n , a n d a n i n d i c a t i o n w h a t t o e x p e c t t h e s e c o n d g e n e r a t i o n t o b e l i k e .
3 . L e a f s h e a t h f e e d i n g - A t y p i c a l d i s c o l o r a t i o n o f t h e l e a f s h e a t h i s c a u s e d b y f e e d i n g o f t h e y o u n g b o r e r l a r v a e b e f o r e t h e y e n t e r t h e p l a n t . T h e s e s i g n s a r e t h e o n l y m e a s u r e o f s e c o n d g e n e r a t i o n i n f e s t a - t i o n s i n f i e l d s w h e r e n o d e a d h e a r t s o c c u r .
4 . J o i n t a n d s t a l k t u n n e l i n g - S i g n i f i c a n t i n j u r y b e g i n s w i t h t h e a t t a c h o f s e c o n d g e n e r a t i o n b o r e r s o n t h e f i r s t 5 t o 7 j o i n t s , a n d c o n - t i n u e s w i t h l a t e r g e n e r a t i o n s m o s t l y o n n e w l y f o r m e d j o i n t s . T h i s t u n - n e l i n g i n t h e l o w e r j o i n t s r e p r e s e n t s t h e m o s t i m p o r t a n t d a m a g e . I t s t u n t s m a n y p l a n t s w h i c h f a i l t o p r o d u c e m i l l a b l e s t a l k s . T h i s a c c o u n t s f o r art u n e v e n t o p l i n e a n d m a k e s t h e s t a n d o f c a n e a p p e a r m u c h l i g h t e r . E y e s s p r o u t o u t , w i t h t h o s e b e l o w g r o u n d p r o d u c i n g l a r g e g r e e n s p r o u t s o r s u c k e r s v e r y low i n s u c r o s e . T o p s d i e a n d f a l l o v e r a n d i n m a n y c a s e s t h e s t a l k s b r e a k i n t w o . B o r e r e n t r a n c e h o l e s a n d e m e r g e n c e h o l e s a r e q u i t e a p p a r e n t u p o n s t r i p p i n g t h e l e a v e s f r o m t h e s t a l k . S p l i t - t i n g o f t h e i n f e s t e d s t a l k r e v e a l s t h e b o r e r t u n n e l s a n d a h i g h i n f e c t i o n o f r e d r o t d i s e a s e i n s u s c e p t i b l e v a r i e t i e s .
T h e s e s t u n t e d p l a n t s , b r o k e n t o p s a n d s t a l k s , t o g e t h e r w i t h e x - c e s s i v e e y e s p r o u t i n g m a k e h a r v e s t i n g e i t h e r b y h a n d o r m a c h i n e v e r y d i f f i c u l t a n d t h e s t o p p a g e s a n d e x t r a s c r a p p i n g i n c r e a s e h a r v e s t i n g c o s t s .
W i t h a n i n c r e a s e i n b o r e r i n j u r y t h e r e i s a c o r r e s p o n d i n g d e - c r e a s e i n y i e l d o f c a n e a n d s u g a r , i n s u c r o s e a n d p u r i t y . S e v e r e i n - f e s t a t i o n s m a y r e d u c e c a n e y i e l d s i n h a l f a n d l o w e r s u c r o s e a s m u c h a s 3 p e r c e n t .
N o w , b o r e r i n f e s t a t i o n s a r e m e a s u r e d i n t e r m s o f p e r c e n t a g e o f j o i n t b o r e d , b u t p e r c e n t a g e o f j o i n t s b o r e d m a y o r m a y n o t b e a g o o d m e a s u r e o f l o s s e s . I n a n e x t e n s i v e s t u d y o f t h e e f f e c t o f d i f f e r e n t l e v e l s o f b o r e r i n f e s t a t i o n u p o n v a r i o u s f a c t o r s , w e h a v e f o u n d t h a t w i t h a n a t - u r a l o r n o r m a l d i s t r i b u t i o n o f b o r e d j o i n t s t h r o u g h o u t t h e s t a l k t h a t f o r e a c h i n c r e a s e o f o n e p e r c e n t i n p e r c e n t a g e o f j o i n t s b o r e d t h e r e i s a c o r r e s p o n d i n g d e c r e a s e o f . 0 9 8 4 j o i n t s p e r s t a l k ; o f . 0 4 5 7 f e e t i n l e n g t h o f s t a l k ; . 0 1 9 5 p o u n d s i n w e i g h t o f s t a l k ; . 0 5 6 6 p e r c e n t i n , s u c r o s e c o n - t e n t ; . 2 0 5 8 t o n s i n y i e l d o f c a n e ; . 8 6 4 7 p o u n d s o f s u g a r p e r t o n ; a n d 4 3 p o u n d s o f s u g a r p e r a c r e . H o w e v e r , t h i s s a m e r e l a t i o n s h i p o f l o s s e s o r d a m a g e t o p e r c e n t a g e o f j o i n t s b o r e d d o e s n o t e x i s t w h e n c a n e i s t r e a t e d w i t h i n s e c t i c i d e s , b e c a u s e t h e i n s e c t i c i d e s h a v e s u f f i c i e n t e f f e c t u p o n r e d u c i n g b o r e r p o p u l a t i o n s t o c h a n g e t h e n o r m a l d i s t r i b u - t i o n o f b o r e d j o i n t s , w i t h t h e h e a v i e s t c o n c e n t r a t i o n r e s u l t i n g i n t h e u p p e r j o i n t s . T h i s i s a m o s t i m p o r t a n t c o n s i d e r a t i o n i n e v a l u a t i n g r e - s u l t s f r o m c h e m i c a l c o n t r o l b y d u s t i n g a n d w i l l b e m e n t i o n e d l a t e r .
C O N T R O L
I t a p p e a r s t h a t t h e o n l y l o g i c a l a p p r o a c h t o t h e s u c c e s s f u l c o n - t r o l o f t h e b o r e r i s a b r o a d , d i v e r s i f i e d c o n t r o l p r o g r a m e m b r a c i n g
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c u l t u r a l , b i o l o g i c a l and c h e m i c a l c o n t r o l p r a c t i c e s , to be l a t e r sup- p o r t e d b y v a r i e t a l r e s i s t a n c e , when and i f r e s i s t a n t v a r i e t i e s a r e p r o - duced. With, the m o r e r e c e n t p r o g r e s s m a d e through r e s e a r c h by the L o u i s i a n a and Houma Stations this p r o g r a m n e a r s r e a l i t y . The author r e c o m m e n d e d such a p r o g r a m in 1943 in L o u i s i a n a Bulletin 3 6 3 . T h i s is c e r t a i n l y the m o s t l o g i c a l m e a n s of attacking the b o r e r p r o b l e m s i n c e it b r i n g s t o g e t h e r the whole s u g a r c a n e a r e a into a unified p r o g r a m and involves the use of all known c o n t r o l p r a c t i c e s .
It should be m a d e c l e a r that it is unlikely that any one c o n t r o l m e a s u r e will e v e r a c c o m p l i s h the d e g r e e of c o n t r o l d e s i r e d , and it is not a m a t t e r of using one or the o t h e r but a combination of them to cope with the e x i s t i n g c i r c u m s t a n c e s on any one p l a c e . The idea that p a r a s i t e s can be u s e d i n s t e a d of dusting should be d i s c a r d e d at once.
We b e l i e v e that the v a r i o u s c u l t u r a l p r a c t i c e s should be the b a s i s of the c o n t r o l p r o g r a m , and should be adopted on a l l cane f a r m s to hold the o v e r a l l b o r e r population to the l o w e s t l e v e l , and then on p l a c e s w h e r e the infestation justifies it c h e m i c a l c o n t r o l should be r e s o r t e d t o . B i o l o g i c a l c o n t r o l m e a s u r e s should be used to the b e s t advantage to s u p p l e m e n t the whole p r o g r a m .
C u l t u r a l c o n t r o l - With the advent of the cane top s h r e d d e r and the a c c u m u l a t i o n of m o r e definite i n f o r m a t i o n on d e s t r u c t i o n of over- w i n t e r i n g b o r e r s i n e a r l y s p r i n g , c u l t u r a l c o n t r o l p r a c t i c e s now a v a i l - able to the cane g r o w e r should b e c o m e r e g u l a r f a r m p r a c t i c e s .
Although the s h r e d d i n g of cane tops is a new d e v e l o p m e n t , it h a s been talked about for a long t i m e . In y e a r s of a light infestation, when the o v e r w i n t e r i n g population of b o r e r s is m o s t l y in the upper joints cut off with the t o p s , the s h r e d d i n g device will g r e a t l y r e d u c e the c a r r y - over of b o r e r s . In s u c h y e a r s as 1953, when stunted s t a l k s , s u c k e r s , b r o k e n tops and s t a l k s c o n s t i t u t e the bulk of the o v e r w i n t e r i n g m a t e r i a l , then the top s h r e d d e r cannot p o s s i b l y be as effective. H o w e v e r , s h r e d - ding the tops will tend to i n c r e a s e b o r e r m o r t a l i t i e s r e s u l t i n g from wrapping of t r a s h in the m i d d l e s ; m a k e s c r a p p i n g of fields much, e a s i e r and m o r e efficient; and c o n s e r v e the o r g a n i c m a t t e r furnished by the tops and t r a s h .
By following the top s h r e d d i n g with p r o p e r u s e of chopping and w r a p p i n g to k i l l b o r e r s in the cane p i e c e s and s t a l k s which e s c a p e the s h r e d d e r , m u c h c a n be a c c o m p l i s h e d in effectively r e d u c i n g the over- w i n t e r i n g b o r e r population.
All o t h e r c u l t u r a l p r a c t i c e s l i s t e d in the s u m m a r y of c o n t r o l r e c o m m e n d a t i o n s at the c o n c l u s i o n of this p a p e r a r e of specific value i n the o v e r a l l c o n t r o l p r o g r a m .
B i o l o g i c a l c o n t r o l - The u s e of p a r a s i t e s is a fascinating thing, and h a s p r o v e d a r e a l a s s e t to the b o r e r c o n t r o l p r o g r a m in c r e a t i n g m o r e w i d e s p r e a d i n t e r e s t . I t i s doubtful that p a r a s i t e s alone will e v e r c o n t r o l the s u g a r c a n e b o r e r i n L o u i s i a n a . N e v e r t h e l e s s , t h e r e a p p e a r s to be a p l a c e for b o t h T r i c h o g r a m m a , the egg p a r a s i t e , as well as l a r - v a l p a r a s i t e s , s u c h as the Cuban and Amazon F l y , for helping to s u p - p r e s s l a t e r g e n e r a t i o n s following the dusting p e r i o d .
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If a field has a sufficiently heavy infestation to justify dusting, c e r t a i n l y T r i c h o g r a m m a will not control the b o r e r in that field as will dusting. The r e l e a s e of T r i c h o g r a m m a should be thought of as a sup- plement to the dusting p r o g r a m . However, it is only logical to a s s u m e that the use of biological and c u l t u r a l control p r a c t i c e s will r e s u l t in ultimate d e c r e a s e in the cane a c r e a g e which will need dusting.
Chemical Control - We think of c h e m i c a l control, or dusting with r y a n i a or cryolite in this c a s e , as an i m m e d i a t e control for an infestation that is heavy enough to do damage in e x c e s s of the cost of the i n s e c t i c i d a l application. It has no equal or a l t e r n a t e for the specific purpose for which it is designed.
Chemical control is r e c o m m e n d e d only where the p r o p e r checking of fields r e v e a l s the b o r e r infestation in a g e n e r a l a r e a to be sufficient!
heavy to justify the e x p e n d i t u r e . F u r t h e r m o r e , it should be done right or not at all.
It is possible h e r e to d i s c u s s only briefly some of the conflicting opinions r e g a r d i n g s u g a r c a n e dusting and the b a s i s of the i n s e c t i c i d a l b o r e r control p r o g r a m .
A knowledge of the habits of the b o r e r and the n a t u r e of cane growth r e v e a l e d the a p p a r e n t need of an e a r l y s e a s o n poisoning program b e c a u s e of the c l e a r l y defined n a t u r e of the f i r s t and the second g e n e r a - tion and the advantages in t r e a t i n g the s m a l l c a n e . T h e r e a r e usually no joints on the plant at the time of f i r s t g e n e r a t i o n attack so the p r o - tection of the plant is of no p a r t i c u l a r value. F i r s t g e n e r a t i o n control is therefore a preventive type, however, its value lies in the fact that it r e d u c e s e a r l y infestations t h e r e b y d e c r e a s i n g succeeding g e n e r a t i o n s which actually do the d a m a g e . Benefits at h a r v e s t t i m e depend upon a n e a r complete d e s t r u c t i o n of the first g e n e r a t i o n over a sufficiently l a r g e a r e a to p r e v e n t reinfestation by l a t e r g e n e r a t i o n s . It is t h e r e - fore n e c e s s a r y that a l a r g e p a r t of the infested a r e a be t r e a t e d so as to l e s s e n the likelihood of an influx of moths from ad jointing infested f i e l d s . F o r i n s t a n c e , s m a l l e x p e r i m e n t a l plots in which a hundred per cent control of the f i r s t g e n e r a t i o n is obtained shows no benefits at h a r v e s t t i m e where s u r r o u n d e d by infested c a n e .
However, during the time of second g e n e r a t i o n attack five to seven joints a r e formed and its control gives actual p r o t e c t i o n to joints and benefits that a r e m e a s u r a b l e at h a r v e s t t i m e . Although some bene- fits a r e lost by injury from reinfestation by l a t e r g e n e r a t i o n s , the los- ses a r e not in p r o p o r t i o n to the p e r c e n t a g e of joints b o r e d b e c a u s e the late injury is m o s t l y in the upper joints where l o s s e s a r e l e s s s e v e r e . Although outstanding h a r v e s t t i m e differences can be d e m o n s t r a t e d in s m a l l plot second g e n e r a t i o n t e s t s , m o r e effective c o n t r o l in the end is dependent upon a sufficiently high kill of second g e n e r a t i o n b o r e r s and a minimum o± r e i n f e s t a t i o n .
The long period of time elapsing from the l a s t application of dust until h a r v e s t t h e r e f o r e p r e s e n t s c e r t a i n r i s k s and n e c e s s i t a t e s n e a r complete t r e a t m e n t of infested a r e a s . The p r e s e n t t r e n d of
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thought is toward extending the c o n t r o l period n e a r e r to h a r v e s t which is now a possibility since s o m e of the newly introduced v a r i e t i e s of cane grow r a t h e r openly at the top allowing dusts to better p e n e t r a t e in l a t e r stages of growth. Very definite benefits are obtained from controlling the third g e n e r a t i o n , especially in s m a l l plant cane where damage may s o m e t i m e s be quite s e v e r e .
Among the m o r e pertinent considerations in a chemical control p r o g r a m of the b o r e r a r e the p r o p e r checking of fields to d e t e r m i n e when and where to dust; p r o p e r timing of dust applications; the use of at l e a s t the r e c o m m e n d e d minimum dosage r a t e s and number of ap- plications; p r o p e r application of the i n s e c t i c i d e ; t r e a t m e n t of g e n e r a l a r e a s and not s c a t t e r e d fields; and wise i n t e r p r e t a t i o n of r e s u l t s , which m e r i t s further explanation.
I n t e r p r e t a t i o n of R e s u l t s from Chemical Control of the B o r e r - It s e e m s i m p o r t a n t that the g r o w e r s should b e t t e r understand the effects of c h e m i c a l control on b o r e r infestations in o r d e r to be in a position to analyze r e s u l t s m o r e a c c u r a t e l y . The following considerations must be kept in mind in p a s s i n g judgement on the efficacy of dusting cane for b o r e r c o n t r o l :
1. Chemical control cannot be expected to eliminate All bored j o i n t s . P r o t e c t i o n of lower joints will allow as much as 35 per cent in- festation of upper joints in cane showing a 6 to« i n c r e a s e from dusting.
2. If r e c o m m e n d a t i o n s a r e followed, the fields selected for dust- ing should m e e t the minimum b w e r infestation r e q u i r e m e n t s which should produce d e s t r u c t i v e infestations by h a r v e s t t i m e . Therefore the dusted a r e a s a r e the ones in which you would anticipate the worst injury so there is no r e a s o n to expect to find l e s s b o r e r s in these than in most of the un- dusted fields, which m a y have s t a r t e d out with little or no b o r e r s .
3. C o m p a r i s o n s of dusted and undusted cane should be made in cane of the s a m e v a r i e t y , s a m e age, s i m i l a r growth, having approxi- mately the same infestation to begin with, and within close proximity so as to be subjected to the s a m e conditions.
4. The undusted fields would c e r t a i n l y be subject to much higher infestations if nothing has been done in the a r e a s showing e a r l y infesta- tions sufficiently heavy to justify dusting.
5. Chemical b o r e r control is more effective some y e a r s than others as is weed c o n t r o l , fertilization and other p r a c t i c e s .
6. Gains from dusting a r e p r o p o r t i o n a l to level of b o r e r infesta- tion. The g r e a t e s t gains or r e t u r n s from the expenditure a r e obtained from the highest infestations, although t h e r e may be m o r e evidence of b o r e r s at h a r v e s t t i m e in such t r e a t e d fields that in fields t r e a t e d for a light infestation.
7. P e r c e n t a g e of joints bored at h a r v e s t t i m e in a dusted field is not a true m e a s u r e of l o s s e s , since the dusting causes a change in the location of the b o r e d j o i n t s , moving the infestation to the upper joints which r e s u l t s in l e s s injury. The percentage of joints b o r e d shortly after the dusting is t e r m i n a t e d is actually a m o r e a c c u r a t e
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m e a s u r e of injury than the h a r v e s t t i m e figure.
8, The protection of the plant from b o r e r injury to the lower joints at the most c r i t i c a l t i m e , in June and July, allows the plant to grow to be a millable stalk r e g a r d l e s s of the l a t e r re infestation in the top j o i n t s .
9. T r e a t e d fields, e s p e c i a l l y for f i r s t g e n e r a t i o n c o n t r o l , may become thoroughly reinfested and e r a s e all benefits of the dusting.
10. F i n a l l y , the aim of a dusting p r o g r a m is to reduce the b o r e r infestation over a whole f a r m or community, so it is unfair to judge r e - sults by what o c c u r s in s m a l l localized a r e a s .
A SUMMARY OF RECOMMENDATIONS FOR CONTROL OF THE SUGARCANE BORER
The following is a brief outline of the m o r e significant r e c o m - mendations.
1. Shredding of cane tops - Shredding of the tops to r e d u c e the number of b o r e r s e n t e r i n g hibernation in joints left on cane tops and to add humus to the soil.
2. Make thorough c l e a n - u p during h a r v e s t - The main s o u r c e of b o r e r infestation in the spring is from cane m a t e r i a l left during h a r v e s t . A s p e c i a l scrapping win often yield enough cane to pay for the operation b e s i d e s reducing c a r r y o v e r of b o r e r s . It is also helpful to r e m o v e all stalks and p i e c e s of cane from r o a d s , r a i l r o a d s , and about the factory and d e r r i c k s .
3 . Burn t r a s h cane p i e c e s , t o p s , e t c . t h o r o u g h l y - Thorough burning r e d u c e s overwintering b o r e r s by 60 to 70 per cent. Shredding of tops would eliminate n e c e s s i t y of burning.
4. Chopping, wrapping of middle, and shaving and wrapping - has been found to reduce overwintering population by 76, 88 and 92 p e r cent, r e s p e c t i v e l y , as c o m p a r e d to 20 per cent where nothing was done.
Thorough burning or shredding is n e c e s s a r y to eliminate bulky t o p s , which wrapped with the p i e c e s l o w e r s m o r t a l i t i e s of the b o r e r s .
5. Shave s u m m e r planted cane and d e s t r o y plants - A heavy b o r e r population may be found overwintering in shoots of s u m m e r planted c a n e .
6. S t a r t s p r i n g cultivation in fields heavily infested the previous y e a r - E a r l y cultivation will d e s t r o y many stages before the moths e m e r g e .
7. Concentrate c o r n plantings and i s o l a t e the plantings if p o s s i b l e - Corn can be a s o u r c e of heavy reinfe station for t r e a t e d c a n e . Concentrated plantings facilitate dusting when needed and p r e - vent s p r e a d of b o r e r s .
8. Cut out and d e s t r o y heavily infested c o r n - Quite frequently heavy f i r s t g e n e r a t i o n infestations a r e c o n c e n t r a t e d in r a t h e r s m a l l a r e a s of e a r l y developing c o r n , which may produce as many as a hundred thou- sand b o r e r s p e r a c r e .
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9. Control the f i r s t , second or third generations by dusting with ryania or c r y o l i t e .
10. R e l e a s e T r i c h o g r a m m a egg p a r a s i t e s to maintain p a r a s i t e population at highest possible level.
11. R e l e a s e of the l a r v a l p a r a s i t e s (Cuban and Amazon flies) - Extensive e x p e r i m e n t a l r e l e a s e s a r e being made by both stations this year to d e t e r m i n e the good that may be derived from them. They a r e not r e c o m m e n d e d at the p r e s e n t t i m e .
12. P l a n t b o r e r - f r e e cane - This i n s u r e s good stands and healthy plant c a n e . G e r m i n a t i o n and vitality of plants may be lowered consider- ably by use of heavily b o r e d seed c a n e .
13. H a r v e s t heavily infested cane as soon as possible - This p r e - vents additional l o s s e s ; allows m o r e time for breaking stubbles; and i n - c r e a s e s overwintering m o r t a l i t i e s through e a r l y h a r v e s t i n g .
14. Cut cane at ground level - Cane should be cut at ground level to r e d u c e number of b o r e r s overwintering in cane s t u b b l e s . Cut- ting of cane lower to include the f i r s t joints also i n c r e a s e s suga-r p r o - duction.
15. F a l l - b r e a k stubble fields - Thorough breaking d e s t r o y s all overwintering m a t e r i a l .
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THE IRRIGATION OF SUGAR CANE By R. J. LeBlanc -- Godchaux Sugar s , Inc.
The purpose of this e x p e r i m e n t is to d e t e r m i n e if t h e r e is some way which is profitable, in the time of drought to be able to give the s u g a r cane its r e q u i r e d amount of m o i s t u r e .
In 195Z a Webster P o r t a b l e i r r i g a t i o n s y s t e m with a Hale pump and 8 cylinder C h r y s l e r engine for the p u r p o s e of conducting e x p e r i - m e n t a l work in the i r r i g a t i o n of sugar cane was p u r c h a s e d .
The s y s t e m cost a p p r o x i m a t e l y $ 8 , 0 0 0 . It has 800 ft. of 8"
aluminum pipe consisting of 40 length 20" long and 1320 ft. of 6" pipe consisting of 66 length 20' long and 8 s p r i n k l e r h e a d s . The 8" pipes are used for the c r o s s line and the 6" pipes for the l a t e r a l l i n e s . T h e r e are enough l a t e r a l pipes (6") to s e t up two l a t e r a l l i n e s , so that while one line is i r r i g a t i n g the other one is being set up so that when the f i r s t line is finished all that is done is close one valve on the d i r e c t i o n a l valve and open the o t h e r . This can be done without stopping the pump.
This machine can i r r i g a t e an a r e a of a p p r o x i m a t e l y 3 sq. a c r e s with a setting at the r a t e of 1 inch p e r hour and the machine s e t at 2200 RPM and can cover an area- of 27 sq. a c r e s before moving the pump.
To o p e r a t e the s y s t e m it takes one man to operate the pump and four men to pick up and s e t up the l i n e . To lay the line down the men c a r r y the pipes down the row and couple them as they go. The pipes are connected together by a T r i g g e r l o c k . To lock, i n s e r t one pipe into a- nother allowing t r i g g e r to d r o p in s l o t . To unlock, push pipe t o g e t h e r , twist slightly and withdraw. After the i r r i g a t i o n is completed on that line the men go down the cut, uncouple the pipes and c a r r y them 200 ft. a c r o s s the cut to where the next setting will be m a d e .
Should it be n e c e s s a r y to extend the 6" line m o r e than 680' the line can be extended up to 980" without the friction l o s s exceeding the pump design head, the only time loss would be the time lost to set up each setting.
The weight of the pipes a r e : the 6" pipe for the l a t e r a l line is 1.365 pound per foot and the 8" pipe weighs 2. 802 pound p e r foot.
The pump is a Hale single stage centrifugal pump d i r e c t l y con- nected to the bell housing of the C h r y s l e r I n d u s t r i a l 8 cylinder engine.
The whole a s s e m b l y is neatly and ruggedly mounted on a s t r u c t u r a l i r o n f r a m e . The d r i v e to the pump is through flexible r u b b e r c u s h i o n s .
At the p r e s e n t time it is too e a r l y to say what good can be de- r i v e d from the i r r i g a t i o n of cane as t h e r e has not been enough work done on this to d e t e r m i n e whether it would be profitable or not.
Work was s t a r t e d on July 15, 1952, this was following a t h r e e
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Pattern of Coverage
4th sprinkler
at
3rd sprinkler
2nd sprinkler
1st sprinkler
160' ; 160'
Clear areas / / / / areas iltfifft ar e a s
Precipitation Spacing with an 8 MPH wind
1.0" per hour . 6 " per hour . 3 " per hour
160' x 200' Spacing with an 4 MPH wind Clear areas 72" per hour
/ / / / areas . 4 8 " per hour
«# areas . 24" per hour
month drought. The cane r e c e i v e d an application of 3 inches of r a i n at the r a t e of 1" per hour covering an a r e a of 160' wide and 680" long. Three days after this cane was i r r i g a t e d we had 1. 8" of r a i n and from then the r a i n continued p e r i o d i c a l l y until S e p t e m b e r . Had it been possible to star;
this work at the beginning of May before the cane had suffered from the drought, r e s u l t s may have been obtained then.
During September through the middle of November there was a- nother drought and the plant cane began to suffer from the lack of mois- t u r e . Then 110.0 a c r e s of plant cane in heavy soil w e r e i r r i g a t e d . In three a r e a s there was a s m a l l number of a c r e s where enough water was not available to complete the section and these w e r e used as check p l o t s . The cane that was i r r i g a t e d r e c e i v e d water at the r a t e of 3 " . In the sprit t h e r e was considerable difference in the cane that was i r r i g a t e d and the one which was not. In some sections that w e r e not i r r i g a t e d the cane did not come up and where it did come up t h e r e was a v e r y poor stand.
In 1953 we followed up the work which we had s t a r t e d in the fall, 122.0 acres w e r e i r r i g a t e d from May 28th through July. After July 1st there was enough r a i n to discontinue the use of the i r r i g a t i o n s y s t e m . However in September the plant cane began to suffer from lack of w a t e r , but due to a shortage of labor we w e r e unable to do any i r r i g a t i o n at the t i m e . Quite a number of acres had to be r e p l a n t e d and m o r e will have to be d e s t r o y e d this s p r i n g .
In the a r e a s that w e r e i r r i g a t e d some r e c e i v e d 1 application of 3"
of r a i n and some r e c e i v e d 2 applications two weeks a p a r t .
The cost of i r r i g a t i o n , taking in g a s , oil and labor was $ 7 . 4 3 / a c r e / a p p l i c a t i o n of 3" of w a t e r . However, this cost does not take in any depreciation on the unit.
R e s u l t s ;
Utopia Plantation; Heavy soil CP3 6-105 plant c a n e . Planted Sept. 23, 1952, i r r i g a t e d Oct. 14, 1952 with 3" w a t e r . This was the only i r r i g a - tion it r e c e i v e d . Yield I r r i g a t e d 1 6 . 0 T / A
Check 13. 5 T / A
Utopia P l a n t a t i o n : Heavy soil CP3 6-105 plant c a n e . P l a n t e d Aug. 12, 1952, i r r i g a t e d Aug. 21 with 3" w a t e r ; October 20, 3" w a t e r ; June 1, 3 " ; June 19, 3 " . Yield I r r i g a t e d 18. 6 T / A
No Check
R a c e l a n d - M a r y P l a n t a t i o n : Heavy Soil CP44-101 plant c a n e . P l a n t e d Sept. 11, 1952. I r r i g a t e d June 10-15 with 3 " w a t e r . Only application it r e c e i v e d . Yield I r r i g a t e d 26. 0 T / A
Check 20. I T / A
Both plots were planted the s a m e day in the s a m e type s o i l . A s p e c i a l e x p e r i m e n t on Co290, CP34-120 and C P 2 9 / 3 2 0 was made to d e t e r m i n e if additional m o i s t u r e w e r e given, whether these v a r i e t i e s would show an i n c r e a s e in yield, or if they had j u s t played out. R e s u l t s :
Co290 15.50 T / A CP29-320 13.72 T / A CP34-120 11.87 T / A
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On September 10, 1952 i m m e d i a t e l y after planting all t h r e e v a r i - eties r e c e i v e d 3" of w a t e r . On Oct. 9, 1952 another 3" of water was ap- plied. On May 28 and June 17 another 3" on each of those dates was put on.
Difficulties experienced with the I r r i g a t i o n System;
You must have a good supply of water available n e a r each sec- tion you will i r r i g a t e . With one s y s t e m it is difficult to cover many a c r e s .
At the time of i r r i g a t i o n it is very difficult to keep the same men on this work, because of the heat in s u m m e r , and many times you have to s t a r t training a new c r e w .
Under the p r e s e n t conditions it is difficult to say how much m o r e work we will be able to do in the future, but if possible more work will be done to see if this work would be profitable and economical to the Sugar I n d u s t r y .
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