The Search for MB Alternatives Continues During 2005.

University of Georgia

Tifton Campus

OBJECTIVES

1. Find effective and economical alternatives

2. Reduce the amount of MB used in GA

Efforts Have Focused

1. Fumigants

2. Mulch Types

3. Herbicides

Fumigants and Rates (2002 to 2004)

1. Methyl Bromide 2. Chloropicrin3. Vapam4. Telone II fb chloropicrin5. Telone II fb metam6. Telone C35 fb chloropicrin7. MIDAS8. DMDS alone and with chloropicrin

Spring 2005 Efforts

1. Replicated small plot research trials2. Replicated field trials (10-20 acres)3. Demonstration trials (>120 acres)

Evaluated over 30 possible fumigant combinations

Fall 2005 Efforts

1. Compared three fumigant alternatives2. Compared various types of plastic mulch

Fumigant Options

1. Telone II fb Chloropicrin fb Vapam

Telone II (12 G) fb Vapam (75 G)

V4-05, 60 DAT

Telone C35 (35 G) fb Pic (150 lbs)

V4-05, 60 DAT

Telone II (12 G) fb Chloropicrin (150 lbs) fb Vapam (75 G)

V4-05, 60 DAT

Fumgiant Options*

1. Telone II fb chloropicrin fb Vapam2. MIDAS (methyl iodide plus chloropicrin)3. DMDS (dimethyl disulfide plus chloropicrin)4. MB (methyl bromide plus chloropicrin)5. None

Soil Properties and Application Method Will Play A Crucial Role

Picture provided by Tony Weiss, Dow Agro.

MIDAS, Bromide, Pic and Exp.

Applications of Telone II

rototiller blades

nozzles for KPAM

Vapam Application

Second Attempt

Metam Application

Fall Fumgiant Treatments

1. Telone II fb chloropicrin fb Vapam2. MIDAS (methyl iodide plus chloropicrin)3. DMDS (dimethyl disulfide plus chloropicrin)4. MB (methyl bromide plus chloropicrin)5. None

Rates are broadcast: Telone II 12 G, chlororpicrin 150 lb, Vapam 75 G; MIDAS (50:50 mixture) 350 lbs; DMDS (80:20 mixture) 750 lbs; MB (67:33) 350 lbs.

Mulches*

1. Low density polyethylene (2 types)2. Metalized smooth (2 brands)3. Metalized embossed 4. VIF (2 brands)

LDPE mulch white on black, metalized mulch silver on white, VIF black on black

Searching For Methyl Bromide Alternatives To Manage Nutsedge

A. Stanley Culpepper and MANY others; University of Georgia

Treatments and Fumigants Applied: July 14, 2005

Prelude II Squash Planted on August 10, 2005.

Photos taken on August 30, 2005.

See Summary Information for application procedures etc.

In Field Cooperators

Hendrix and Dale

John Mirusso

Dow Agro SciencesArvesta

Cerexagri

MB 76 ab

MIDAS 79 a

DMDS 69 ab

T2+Pic+Vapam 77 ab

Fumigants LDPE

Percent Nutsedge Control by Fumigants. Ponder Farm, 2005.

MB 76 ab ($450)*

MIDAS 79 a ($??)

DMDS 69 b ($??)

T2+Pic+Vapam 77 ab ($362)

Fumigants LDPE

Percent Nutsedge Control by Fumigants. Ponder Farm, 2005.

*Culpepper’s cost per acre for 2006. Three way 24% cheaper than MB at 350 lb.

MB 76 de 94 ab

MIDAS 79 cd 94 ab

DMDS 69 e 99 a

T2+Pic+Vapam 77 de 87 bc

Fumigants LDPE

Percent Nutsedge Control by Fumigants Applied Under Various Mulches. Ponder Farm, 2005.

Metalized Smooth

MB 76 cde 94 ab 82 bc

MIDAS 79 cd 94 ab 83 bc

DMDS 69 def 99 a 65 ef

T2+Pic+Vapam 77 cd 87 abc 63 f

Fumigants LDPE

Percent Nutsedge Control by Fumigants Applied Under Various Mulches. Ponder Farm, 2005.

Metalized

smooth embossed

MB 76 c-f 94 ab 82 bcd 100 a

MIDAS 79 cde 94 ab 83 bcd 100 a

DMDS 69 def 99 a 65 ef 98 a

T2+Pic+ Vapam

77 c-f 87 abc 63 f 90 abc

Fumigants LDPE

Percent Nutsedge Control by Fumigants Applied Under Various Mulches. Ponder Farm, 2005.

Metalized

smooth embossed VIF

No fumigant

MB 350 lb/A Broadcast, LDPE Mulch

White Surface

MB 350 lb/A Broadcast, Metalized Smooth Mulch

Silver Surface

MIDAS 350 lb/A Broadcast, LDPE Mulch

White Surface

MIDAS 350 lb/A Broadcast, Metalized Smooth Mulch

Silver Surface

White Surface

Telone II (12 Gal) fb Pic (150 lb) fb Vapam (75 G) Broadcast, LDPE Mulch

Silver Surface

Telone II (12 Gal) fb Pic (150 lb) fb Vapam (75 G) Broadcast, Metalized Smooth Mulch

White Surface

DMDS 750 lb/A Broadcast, LDPE Mulch

Silver Surface

DMDS 750 lbs Broadcast, Metalized Smooth Mulch

Much research is still needed on metalized mulches:

1. Interval between fumigating and planting.

VIF LDPE

Telone II fb chloropicrin

Transplanted 21 DAT

Much research is still needed on metalized mulches:

1. Interval between fumigating and planting.

2. Difficulty to lay.

3. Flaking.

4. Longevity compared to standard LDPE mulch.

5. Verify results noted in this trial.

6. Higher price.

MB $748 $1008

MIDAS ?? ??

DMDS ?? ??

T2+Pic+ Vapam

$659 $920

Fumigants LDPE

Cost of Systems Per Acre, 2006.

Metalized

smooth

Can we reduce the rate of these fumigants when applied under

metalized smooth mulch?

Number of Nutsedge Emerged Through Mulch with Methyl Bromide Applied Under LDPE or Metalized

Smooth Mulch. 4 WAT. LTF, Fall 2005.

0

20

40

60

80

100

120

140

MB 400 lb, LDPE

MB 300 lb, LDPE

MB 300 lb, Met. S

MB 200 lb, Met. S

a

d

b

c

Plots were 3 beds by 1500 row feet. Counts made on 3 beds 400 row feet.

Not Saying There is a Consistent MB Alternative BUT its Time to Try Some Things!!

Questions or Comments?