July 2007 Sugarcane Newsletter

7/9/2007 6:25:40 PM

Picture of Sugarcane

 DISASTER PAYMENTS: Mr. Willie Cooper, USDA-FAS, reported at the recent Louisiana Farm Bureau Meeting at New Orleans that there were no appeals with regards to the sugarcane disaster payment. The $1 million that was held for appeals has now been distributed to the factories, producers and landowners, where applicable.

VARIETIES. On April 26, 2007, the Variety Release Committee consisting of representatives from the LSU AgCenter, the USDA-ARS, SRRC, Sugarcane Research Laboratory and the American Sugar Cane League of the USA, Inc. made it official that HoCP 00-950 will be released to the Louisiana sugarcane industry in the late summer, early fall of 2007. HoCP 00-950 is a product of the cross HoCP 93-750 x HoCP 92-676 made at Canal Point (CP) Florida in 1995 and selected at Houma (Ho), Louisiana, in 1997. The cultivar has a high population of medium-sized stalks that turn greenish-yellow when exposed to sunlight. Outfield data for this and the other new varieties can be found in the July issue of The Sugar Bulletin as well as the application for seed cane of the newest variety. To reiterate what was mentioned in the last newsletter in May, HoCP 00-950 is known for its early high sucrose content; it has an exceptionally high yield of recoverable sugar per ton of cane both early in the season as well as at the end of the season.

HoCP 00-950 has good tonnage, stubbles well and has superior yield of recoverable sugar per acre through the second-stubble crop when compared with the control variety, HoCP 96-540. It has adequate resistance to all the major diseases with the exception of ratoon stunting disease (RSD) although there is some concern that it had a high level of infection to leaf scald in inoculated tests. There was little or no leaf scald found in the field. It is essential that seed cane of this cultivar be free or nearly free of RSD in order for it to yield to its fullest potential. It is also very susceptible to damage caused by the sugarcane borer and should not be planted where insecticides can not be applied. Seed cane will be available through the secondary stations overseen by the agronomists of the American Sugar Cane League.

At the same meeting, the Variety Release Committee also made available three varieties, L 79-1002, HoCP 91-552 and Ho 00-961, for the emerging biofuel industry with higher fiber than found in commercial varieties released for sugar. For more details of these varieties see the May sugarcane newsletter. Seed cane of all three high-fibered varieties will not be available for distribution by the American Sugar Cane League, the United States Department of Agriculture, or the Louisiana Agricultural Experiment Station. However, the varieties will be available through private seed cane companies, i.e. Kleentek, and the National Plant Germplasm System at the National Germplasm Repository located on the Subtropical Horticulture Research Station in Coral Gables, Florida.

Growth Measurements. The crop continues to make excellent growth in most areas of the State with adequate rainfall and the warm to hot temperatures as the catalyst. There are still some older stubble fields, especially of the variety LCP 85-384, that are short, gappy and now weedy. Plant cane stands, especially of the new varieties, are generally good to excellent.

Growth measurements from Jeanerette (Iberia Research Station, LSU AgCenter) and Chacahoula (USDA-ARS, SRRC, SRL) indicate that HoCP 96-540 is below average in the plant-cane crop when compared to last year and above average in the first-stubble crop when compared to last year. Growth measurements for LCP 85-384 are below average for both the plant cane and first-stubble crops when compared to last year. However, the current growth rates for all varieties being measured at the two locations, with the exception of LCP 85-384 in the first-stubble crop at Houma, exceeded one inch a day for the week ending July 3 or 5 at Chacahoula and Jeanerette, respectively, which is normal for this time of year. Again growth rates at the two locations are similar when comparing the same varieties.

Dr. Sonny Viator, LSU AgCenter, noted that the cane growth at the Iberia Research Station for the week ending July 5 was the best seen thus far this year. The first-stubble crop of L 97-128 actually grew almost 11 inches for the week. He said it was interesting to note that the Iberia Research Station had received about 10 inches of rain year-to-date (YTD) more than the Chacahoula location. Dr. Viator indicated that the height of the cane at Houma is about average for this time of year even though the rainfall is below average for the year. The total rainfall for Chacahoula is 23.4 inches while the Iberia Research Station has received 32.1 inches YTD.

The old adage of having at least four joints by the fourth (of July) is pretty much true throughout the sugarcane belt which means that we have a decent crop in the making for this time of year. Of course, the sugar is not in the warehouse but it is good to see excellent progress at this time of year. In fact, there have been several reports that with the recent thunderstorms and associated wind, there has been some cane to lodge; however, it is not expected that this will have any long lasting impact on the crop.

WEED CONTROL RECOMMENDATIONS. According to Dr. Ed Richard, USDA-ARS, SRRC, SRL, tie vines are emerging as the major weed pest at this time of year, especially in fields receiving early lay-by treatment and because of the frequent rains. He also noted that fallow fields are getting weedy because of the frequent rains. Specific recommendations on post-emergence weed control after layby were supplied by Drs. Richard and Caleb Dalley, USDA-ARS, and Dr. Jim Griffin, LSU AgCenter. They are as follows:

Postemergence Weed Control After Layby

Rainfall combined with high soil temperature contributes to rapid degradation and loss of weed control from herbicides applied at layby. Grass weeds emerging after layby generally do not reduce sugarcane yield or interfere with harvest. However, morningglory or tie-vines can cause significant problems at harvest particularly when the chopper harvester is used. To control morningglory and other broadleaf weeds, herbicides can be applied over the crop canopy by air or by ground sprayer, or herbicides can be directed underneath the crop canopy using a high clearance sprayer. When crop injury from the herbicide is not of concern, coverage of the entire morningglory plant with spray solution will provide more consistent control. Nonionic surfactant at 1 to 2 qt/100 gal or crop oil concentrate at 2 to 4 qt/100 gal should be added to the spray solution.

2,4-D is commonly applied at this time of the year, however, its use is restricted in some parishes. Check local restrictions before application. To avoid potential stand and yield loss in the subsequent plant cane crop, 2,4-D, Clarity, Vision, Weedmaster, Brash, or Kambamaster should not be applied to seed cane sources closer than 7 weeks prior to harvest and planting.

Rate of Formulated
Material for 1 Acre Broadcast

Active Ingredient

Weeds Controlled
(see “Weed Control with Sugarcane Herbicides” section)


2,4-D products 3.8L

1.0 – 1.5 qt

(see information below on 2,4-D formulations)


0.47 – 1.42 lb/A

Morningglory (tie-vine) and other broadleaf weeds

Apply higher rate if vines are climbing sugarcane plants. Complete control may take in excess of 5 weeks. Surfactant can be added but is not required. Note restrictions on use in some parishes and on sugarcane used for seed.

AAtrex 4L, Atrazine 4L
2.0 – 4.0 qt
AAtrex Nine-O, Atrazine 90DF, Atrazine 90WDG
2.22 – 4.44 lb


2.0 – 4.0 lb/A

Morningglory (tie-vine) and other broadleaf weeds

Can be applied overtop or directed before row closure occurs. Use higher rate if vines are climbing sugarcane plants.

Clarity 4L

16.0 – 24.0 oz


Vision 3.8L

17.0 to 25.0 oz

dicamba 0.5 – 0.75 lb/A

Morningglory (tie-vine) and other broadleaf weeds

Apply higher rate if vines are climbing sugarcane plants. Complete control may take in excess of 5 weeks. Surfactant can be added but is not required. Note restriction on sugarcane used for seed. Can be used in parishes where 2,4-D use is restricted.

Envoke 75DF

0.3 oz – 0.6 oz


0.014 – 0.028 lb/A

Morningglory (tie-vine) and other broadleaf weeds, itchgrass and other annual grasses, and purple and yellow nutsedge

Apply as a directed treatment.

Permit 75DF
0.67 – 1.33 oz

0.031 – 0.062 lb/A

Purple and yellow nutsedge

Apply until row closure occurs. The higher rate is needed for control. Can be applied with other herbicides.

Spartan 4F

10.0 – 12.0 oz

sulfentrazone 0.313 – 0.375 lb/A

Morningglory (tie-vine) and other broadleaf weeds

Apply as a directed treatment and use higher rate if vines are climbing sugarcane plants. Spartan can be applied more than once during the growing season but total usage per twelve-month period can not exceed 12 oz/A. If applied in the spring or at layby do not reapply. An interval of at least 120 days between application and harvest is specified.

Valor SX 51WG

3.0 – 8.0 oz


0.096 – 0.255 lb/A

Morningglory (tie-vine) and other broadleaf weeds and some annual grasses

Apply only as a directed treatment after sugarcane has begun to joint. Spray solution should contact no more than the lower six inches of sugarcane plants. At the 3 to 4 oz/A rate good control of emerged morningglory can be obtained. If long term control is desired 6 to 8 oz/A should be applied. Valor can be applied at a maximum rate of 12 oz/A per crop year. Treatment to harvest interval should be at least 90 days.


Kambamaster 3.87L

0.5 – 1.0 qt

2,4-D plus dicamba

0.72 + 0.25 lb/A

Morningglory (tie-vine) and other annual broadleaf weeds

Apply higher rate if vines are climbing sugarcane plants. Complete control may take in excess of 5 weeks. Surfactant can be added but is not required. Note restrictions on use in some parishes and on sugarcane used for seed.

Gramoxone Max 3L

1.33 – 2.7 pt


Gramoxone Inteon 2L

2.0 – 4.0 pt


0.50 – 1.0 lb/A

Bermudagrass and small grass and broadleaf weeds

Application to the row middles in late June desiccates bermudagrass, and combined with shading from the crop canopy can reduce bermudagrass regrowth. Herbicide contact to young sugarcane tillers can cause significant injury. Application can reduce the amount of bermudagrass transported with seed cane.

2,4-D Formulations:

Formulations of 2,4-D on the market include acid, amine salts, and esters. Since only the acid form of 2,4-D is active in controlling weeds, the herbicide concentration on the label is provided in lb ae (acid equivalent)/gal instead of lb ai (active ingredient)/gal, as is the case with most other herbicides. Formulations of 2,4-D range from 1.74 to 5.6 lb ae/gal. These numbers are important in determining the amount of formulated product to apply per acre. The lower the lb ae/gal the more formulated product required. For example, a 32 fluid oz rate (1 qt/A) of a 3.8L formulation would correspond to 21.7 oz for a 5.6L formulation and 70 oz for a 1.74L formulation. Unison is an acid formulation of 2,4-D and contains 1.74 lb ae/gal. Although this formulation of 2,4-D is not volatile (susceptible to converting to a gas and moving off-target) it would still be susceptible to physical drift as a liquid. Caution should be used anytime 2,4-D is applied near sensitive plants regardless of formulation.

BERMUDAGRASS CONTROL IN FALLOW SUGARCANE FIELDS. Dr. Dalley, USDA-ARS offered the following recommendations for bermudagrass control in fallow sugarcane fields. Fallow fields provide the optimal conditions for gaining control of one of our worst sugarcane weeds, bermudagrass. However, many fallow fields this year have become very weedy due to the frequent rainfall that has limited tillage and spray operations. In some parts of the state, much of the fallow ground remains flat-chopped as it has been too wet to draw rows. In fields where bermudagrass is a problem this will increase the difficulty of obtaining satisfactory control before planting begins, as this is less than one month for some fields. So in order to gain an advantage we must act quickly.

For bermudagrass infested fields that remain flat-chopped and are too wet to cultivate or form rows, a glyphosate herbicide (Roundup, etc.) should be applied as soon as possible at a rate of 2 to 3 qt per acre of the 4L formulation (adjust accordingly to formulation used). Use the higher rate if bermudagrass only if infestation is severe. Do not cultivate or form rows for at least one week following glyphosate application to allow the glyphosate to be absorbed into the roots and rhizomes. One to two weeks prior to planting a second application of glyphosate at 2 to 3 qt per acre may be applied if regrowth of bermudagrass occurs.

For fallow fields with rows established where bermudagrass is a problem, glyphosate should be applied at 2 to 3 qt per acre six weeks prior to planting and then again at two weeks prior to planting, if bermudagrass regrowth is observed, the higher rate should be used if infestation is severe. When applying glyphosate, take precautions not to allow spray to drift onto established cane fields or onto other sensitive crops.

For fallow fields also infested with tie-vines/morningglories, glyphosate can be tank-mixed with Aim EC® herbicide at a rate of 1 to 2 oz per acre (add Aim EC® to tank first before adding glyphosate product). Aim will not interfere with bermudagrass control but will improve control of tie-vines which are sometimes inadequately controlled with glyphosate alone. Aim requires the use of a non-ionic surfactant (2 pints per 100 gallons of spray solution) or crop oil concentrate (1.5 to 2 gallons per 100 gallons of spray solution) unless it is tank-mixed with an herbicide already containing a surfactant.

Control of bermudagrass in fallow fields reduces infestations during the plant-cane and stubble crops. However, in order to slow re-infestation, herbicides with activity on bermudagrass should be applied (such as Command, K4, Sencor, or Sinbar) following planting. See the LSU Weed Control Guide for recommendations.

DISEASES. Dr. Jeff Hoy, LSU AgCenter, has noted that rust has now re-established itself all the way to the top of the industry. He saw some moderate rust in plant cane of LCP 85-384 at Hamburg just north of Simmsport in Avoyelles Parish. The disease has continued to spread northward during June like it did during 2005 following winter freezes and a cool spring. Rust is now evident in LCP 85-384 stubble in many areas. It is generally not severe, but you can see the rust looking down rows. Rust also is evident in plant cane of Ho 95-988 in many places. He has not seen more severe cases of rust levels in HoCP 96-540. Most fields have a nice dark green color. Further, he has not heard of or seen any problems in the other new varieties. The crop should grow out of the rust soon. Ho 95-988 fields still seem to recover sooner than fields of LCP 85-384. Overall, the impact of rust should be much less than last year. The impact is determined by how long the rust persists. Rust starting in June will not reduce yield like rust starting in April.

We were unable to get a Section 18 for fungicides for rust control during 2007. We will try again next year. Fungicide testing is continuing, and some have been identified with potential for use on farms. Nothing is currently labeled for use in cane. This means that no fungicide is labeled for rust control at this time.

Dr. Hoy indicated that smut can be seen in L 97-128 and Ho 95-988. The highest levels are seen in L 97-128. He does not have a lot of reports or observations, so it seems that smut pressure is lower this season than last year. Winter freezes tend to reduce smut incidence the following growing season.

The wet weather seems to have favored the development of a minor disease with the exotic name of “pokka boeng.” L 97-128 will show symptoms of pokka boeng, such as twisting and malformations in the leaf whorl at the stalk apex and occasionally abnormal tissue growth at nodes and “knife cut” wounds in the stalk rind. This disease is caused by a fungus, Fusarium. The incidence and impact of this disease is usually minor.

INSECTS. According to Drs. Gene Reagan and Dale Pollet, LSU AgCenter, there has been some spraying for borers but for this time of year it is light. They are picking up most of the infestations where there was heavy use of Thimet or moderate to heavy rains. Confirm would be the choice of treatment followed by the pyrethroids on subsequent applications. They indicated that there are some white aphid populations in a few areas on varieties L 97-128 and Ho 95-988, with lady beetle populations. No aphids have been found on HoCP 91-555 and HoCP 96-540. In the areas most affected by the tidal surge in 2005 following Hurricane Rita, Dr. Reagan is seeing a good resurgence of predators in the heavy lands but less in the sandy lands although they are returning.

According to one consultant, borer populations are definitely increasing. Seems like most of the acres being treated are in the Lafourche and Iberia Parish areas. Several consultants reported treating large areas in the 20-100+ acres. Appears there is some treating for borers along the Mississippi River. It is anticipated that more area will be treated during the next several weeks. “Although treatment for borers has been light up until now it is shaping up to be a bad borer year”, says one consultant.

MISCELLANEOUS. According to Dr. Ryan Viator, USDA-ARS, SRRC, SRL, there is a lot of weedy fields at this time because of the rain. He says that this "green manure" in rows needs to partially decompose before planting. He recommends the use of Sencor with crop oil as a possible aid in cleanup although you might want to get such a recommendation from Drs. Richard, Dalley or Griffin. He says this green manure hurt stands just as bad as turning under soybeans. Dr. Viator thinks that this is mostly due to lack of seed to soil contact. Depth of cover should be 2-3 inches. Plant early; the plant cane yield increase will more than compensate for increased seed cost. Farmers need to lap cane well if hand planting, especially with HoCP 96-540 because the top nodes can still be rather immature. Many of the new varieties have long internodes (joints); therefore, it is recommended to plant three stalks and a lap. However, this will still mean less eyes per acre when compared to what we are used to with LCP 85-384.

Don’t hesitate to contact me or any of the authors if you should have any questions or comments.

Benjamin L. Legendre, Ph.D.
Director, Audubon Sugar Institute
Sugarcane Specialist & Denver T.
Loupe/American Society of Sugarcane
Technologists Sugar Heritage Professor
LSU Ag Center Research & Extension
St. Gabriel Research Station
5755 LSU Ag Road
St. Gabriel, LA 70776
Phone: (225) 642-0224
Mobile: (225) 281-9475FAX: (225) 642-5339

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