Weed Management Systems in Florida Sugarcane

Calvin Odero

TREC Seminar Series

Everglades Research & Education CenterWeed Science

• Research (35%)

• Extension (65%)

• Crops

‒ Sugarcane

‒ Vegetables

‒ Bioenergy crops

‒ Rice

‒ Commercial sod

Everglades Agricultural Area

• 700,000 acres of land– Major crop - sugarcane– Other crops – vegetables,

rice & sod

• 416,000 acres of sugarcane– 78% on muck (organic) soils

(Histosols)– 22% on mineral (sandy)

soils (Spodosols & Entisols)

Source: http://www.doi.gov/pmb/oepc/wetlands2/v2ch7.cfm

Muck soils

• Formed ~5,000 years– Decaying saw grass &

marsh plants under flooded conditions

• High soil organic matter content– Up to 85%

• Soil depth– 6 inches to over 4 feet

Muck soil subsidence

• Drainage of soils resulted in – Oxidation & mineralization of

large quantities of organic N

• Microbial oxidation – 50 to 75% of the subsidence

• Subsidence rates for EAA Histosols – 0.13 to 1.71 inches/year

In 1924 a 9ft post was driven into the bedrock at the EREC

Sugarcane taxonomy

• Giant grass (Poaceae)• Tribe: Adropogoneae • Saccharum officinarum L.• Saccharum officinarum L. is

– ‘Noble cane’ with long, thick, heavy, juicy & sweet stalks

• Other species– S. barberi– S. robustum– S. sinese– S. spontaneum

• Commercial clones are typically 3-part hybrids

General agronomy

• Sugarcane is perennial that is harvested annually • Planting season: mid-October to end-December• The first year is referred to as plant cane and the successive years

are ratoon or stubble crops • Harvest season: mid-October to March/April

– Plant cane (1st year): 13-18 months – 1st ratoon ≈ 11 months – 2nd ratoon until final year ≈ 10 to 11 months – Final ratoon (early harvest plow-out) ≈ 8 to 10 months

• Typically replanted every 3 to 5 years• Planting

• Following fallow period‒ Temporary rotation with different crops following final ratoon

• Successive‒ Replanting several weeks after final ratoon

Furrowing for planting

• 3 or 5 furrows made in one pass• GPS guided

• Furrows typically 4-6 inches deep5 ft

Fertilizing before planting

Fertilizer is Broadcasted or Banded in the furrow

• Custom blended fertilizer• Primary nutrients applied

‒ P, K, Mg‒ Cu, Zn, Mn, B‒ N (mostly on sand soils)

Seed cane

Seed cane loading

Whole stalk seed cane is loaded on wagons using a “Grab Loader”

• 2 to 6 crews depending on size of operation

• 30 to 120 A/day

Hand planting sugarcane

• 8 or 9 people crews

‒ 4 droppers

‒ 4 choppers

Covering sugarcane after planting

Weed management in sugarcane

• Major cost associated with sugarcane production• Successful weed control is essential• Weeds can reduce sugarcane yields by competing

– Moisture, nutrients & light

• Several weed species serve as alternate hosts– Disease & insect pests

• Weed control is most critical early in the season prior to sugarcane canopy closure over the row middles

• Weeds that mature and produce seed become– Source of seed bank replenishment – Source of re-infestation in subsequent years

Common weed species

Grass & grass-like weeds

• Fall panicum*

• Guineagrass• Goosegrass• Bermudagrass*

• Almum sorghum• Elephantgrass• Yellow nutsedge*

• Purple nutsedge

Broadleaf weeds

• Common lambsquarters*

• Amaranths*

• Common ragweed*

• Common purslane• Alligatorweed• Nightshades

Common lambsquatersSpiny amaranthAmerican blacknightshade

Weedy and woody host plants of the sugarcane root weevilOdero et al. 2013. J Ento Sci 48:81-89Odero et al. 2015. J Ento Sci 50:3-13

Coffee senna

Spiny amaranth

Common purslane

Sugarcane

Fall panicumBermudagrass

Weed control: crop rotation

• Crop rotation patterns will affect weed management– Leafy greens, sweet corn, snap bean,

radishes, rice

• Fallow period has effectively been used to manage troublesome perennial weeds– Mechanical cultivation & herbicide application

• Flooding fallow fields also aids in weed control

Head lettuceSnap beansRiceSweet corn

Weed control: crop competition

• Crop competition for sunlight is important

• A good stand of sugarcane – Emerge rapidly & uniformly – Form a complete canopy– Shade the row middles early in the season

• Loss of sugarcane stools in ratoon crops– Rodent, insect, or harvest damage – Create open spaces in the cane canopy

• Maintaining maximum sugarcane populations throughout all production phases– Benefits weed control efforts

Fall panicum

Bermudagrass

Weed control: cultivation

• Economical means of suppressing weed growth• Sugarcane plants get the early advantage in the competition for light

– Height differential must be established between cane plants and weeds

• Preemergence herbicides are most effective in establishing this height differential

• Only when the sugarcane plants are growing taller than competing weeds can mechanical cultivation be effective

• Cultivation when weeds are not present due to application of a herbicide or previous cultivations are not recommended

• Cultivation when weeds are not present can – Encourage germination of additional weed seeds– Remove the layer of herbicide present for soil-applied herbicides

• In ratoon crops, mechanical cultivators must – Cut through surface debris and thoroughly mix the soil– Row middles

Weed control: herbicides

• Useful and economical tools in sugarcane production• Must be incorporated into an overall management plan

to obtain their maximum benefit.• Sugarcane must have the initial competitive advantage

against weeds• Application

– Preemergence (PRE)– Postemergence (POST)– POST-directed

• Sprayer calibration is important before herbicide application

Weed control: herbicides

Preemergence

• Atrazine• Metribuzin• Pendimethalin

Postemergence

• 2,4-D• Dicamba• Ametryn• Atrazine• Metribuzin• Asulam• Halosulfuron• Trifloxysulfuron

Preplant/Preemergence/Fallow• Glyphosate

Dissipation of oil-based pendimethalin Dissipation of water-based pendimethalin

Odero & Shaner. 2014. Weed Technol 28:82-88

Preemergence herbicides

Preemergence herbicides

Dissipation of atrazineDT50 4-10 days

Dissipation of metribuzinDT50 19-24 days

Odero & Shaner. 2014. Weed Technol 28:578-586

Broadleaf weeds2,4-D, dicamba, atrazine, metribuzin, mesotrione

GrassesAsulam, trifloxysulfuron, ametryn*, metribuzin*

SedgesHalosulfuron

Postemergence herbicides

Lumax

• A commercial premix of – Atrazine (110 g/L)– Mesotrione (30 g/L), – S-metolachlor (300 g/L)

• PRE or early POST – Control of fall panicum & other weed species

S-metolachlor PRE

Mesotrione POST

Control

Premix 1x POST

Premix 1x PRE

Non-crop areas

Herbicide treatment

Rate

Controlc 3 WAT 6 WAT 9 WAT

Location 1 Location 2 Location 1 Location 2 Location 1 Location 2 (g ai ha-1) -------------------------------------------------%------------------------------------------------- Aminocyclopyrachlor + chlorsulfuron + NIS 83 + 33 88 75 100 100 100 100 Aminocyclopyrachlor + chlorsulfuron + NIS 166 + 66 94 88 100 100 100 100 2,4-D amine 1120 45 56 28 89 40 93 2,4-D amine 2240 74 71 93 100 94 99 Aminopyralid + NIS 70 b 80 76 100 100 100 100 Aminopyralid + NIS 123 b 88 78 100 100 100 100 Clopyralid 105 b 48 35 53 68 50 69 Clopyralid 210 b 54 35 96 88 98 98 Flumioxazin + NIS 53.5 35 8 29 25 26 18 Flumioxazin + NIS 107 33 8 34 45 30 48 Fomesafen + NIS 210 33 35 26 64 20 55 Fomesafen + NIS 420 58 59 70 59 74 45 Oxyfluorfen + NIS 224 11 2 13 23 13 29 Oxyfluorfen + NIS 450 17 14 18 49 23 49 Saflufenacil + dimethenamid-P + MSO 40 + 350 100 100 100 100 100 100 Saflufenacil + dimethenamid-P + MSO 90 + 790 100 100 100 100 100 100 Imazapic + NIS 2.8 b 69 53 75 81 75 66 Imazapic + NIS 5.6 b 79 51 91 84 93 61 Imazethapyr + NIS 35 b 48 24 33 23 45 25 Imazethapyr + NIS 70 b 45 33 24 33 20 14 Mesotrione + COC 52.5 14 13 15 49 20 48 Mesotrione + COC 105 13 7 20 39 26 35 Glyphosate 420b 5 0 15 0 23 0 Glyphosate 840b 9 0 26 10 18 1 Glufosinate 127 60 84 40 79 48 75 Glufosinate 254 86 96 86 91 93 85 Paraquat + NIS 420 19 4 24 19 25 10 Paraquat + NIS 840 10 7 15 30 18 10 Hexazinone 560 100 100 100 100 100 100 Hexazinone 1120 100 100 100 100 100 100 Untreated check 0 0 0 0 0 0 LSD (0.05) 16 13 23 22 26 30

Fernandez et al. 2015. Weed Technol 29:233-242

Contact information

Calvin Odero

Phone: 561-993-1509

Email: dcodero@ufl.edu

http://erec.ifas.ufl.edu/weeds/

THANKS

QUESTIONS?