d.k. lauer

Silvics Analytic

Timing of Site Preparation and Post-Plant Weed Control to

Optimize Pine Growth

Integration of research results from

three region-wide studies

D.K. Lauer

Silvics Analytic

South US Timber TypesPercent of 201 Million Acres

From: Wear and Greis 2002. Southern Forest Resource Assessment

15%

Pine plantation

Natural Pine

Mixed Oak-Pine

Upland Hardwood

Lowland Hardwood

Silvics Analytic

Associated Vegetation Loblolly pine (Pinus taeda L.) range

Southeast U.S.

• 490 species estimated across just 13 pine plantation study sites (Miller et al. 2003)

• 68 species of trees• 33 species/genera of shrubs• 140 genera of herbaceous and others

Silvics Analytic

2 Major FindingsVegetation Control

Strategy

Silvics Analytic

Early benefits of herb control can be negated by woody vegetation!

(from Miller et al. 2003 SJAF)

Age 15 merchantable volume

0

500

1000

1500

2000

2500

3000

3500

4000

Vo

lum

e (

ft3 a

c-1)

Herb Herb ControlControl

Herb + Herb + WoodyWoodyControlControl

Silvics Analytic

Can double production by eliminating competing vegetation!

(from Miller et al. 2003 SJAF)

Age 15 Merchantable Volume

0

500

1000

1500

2000

2500

3000

3500

4000

Vo

lum

e (f

t3 a

c-1)

None

Herb Control

Woody Control

Herb+Woody Control

GOAL

Silvics Analytic

Operational Strategy• Chemical site prep

• Control arborescent woody• Control woody shrubs• Provide initial herbaceous control

• Post-plant Herbaceous weed control• Extend herbaceous control

Silvics Analytic

2001 and 2002 BASF Study Locations

4 Chopper Timing with Bedding

5 LCP HWC after Chopper Site Prep

3 UCP HWC after Chopper Site Prep

Silvics Analytic

Chopper TimingHistorical Use Guidelines

• Chopper + triclopyr targeted for later season:• Perception of enhanced performance• Perception of improved residual control

• Timing relative to bedding• Apply at least 4 weeks before• Wait for good re-growth after bedding

Silvics Analytic

Chopper Timing - Results New Guidelines Relate to

• When bedding is done

• When applications are made

• Application timing

• Season of application

Silvics Analytic

Study Series 2001-1Chopper Timing with Bedding

4 Locations

• 48 oz Chopper + 1 or 2 pints Garlon 4 + 5 qt MSO

• No post-plant HWC

Silvics Analytic

Chopper Timing with Bedding Series

• Mid-season or late-season bedding

• Applications before and after bedding

After BedBefore Bed

Silvics Analytic

Acknowledgements

• Study sites and operational bedding provided by: • Boise Cascade• Foley Timber and Land Company• Plum Creek Timber Company• Rayonier

Silvics Analytic

• Locations– Oakdale, LA (Caddo-P to MW Silt-loam)– Whiteville, NC (Torhunta-VP to P Sandy-loam)– Yulee, FL (Goldhead-P sand w/clay loam subsoil)– Tennille, FL (Leon-P fine sand)

• Common Species– Maples, sweetgum, bays, waxmyrtle, herbs– Gallberry, redroot, grasses– Blackberry

Study Sites

Silvics Analytic

Mid-Season Bedding

Silvics Analytic

Mid-season Bed - Application Timeline

0

1

2

3

4

0 50 100 150 200 250 300 350

Day of year

Lo

cati

on

Before Bed After

Feb 24 May 23 July 25 Nov 6

Silvics Analytic

Chopper Application Timing Mid-season bedding

Vegetation - June of 1st growing season

0

20

40

60

80

100

Untreat

ed

Befor

e M

ar 2

AprilM

ay

June-

July

0 day

s af

ter

1-2

wks

afte

r

3-6

wks

afte

r

7-9

wks

afte

r

> 9

wks

afte

r

Co

ver

(%) Herb

Woody

--- Before Bed --- ------- After Bed -------

Silvics Analytic

Yulee LocationAugust 22, 2001- Untreated Plots

11 weeks after June 7 bed 13 weeks before Nov 19 bed

Silvics Analytic

Yulee, FLNovember 6, 2001

App 1 day before June 7 bed App just hours after June 7 bed

Silvics Analytic

Tennille, FLFebruary 24 Application

February 24, 2001 August 21 – 13 weeks after bed

Silvics Analytic

Tennille, FLAugust 21, 2001

App 2 days before May 23 bedUntreated Check – May 23 bed

Silvics Analytic

Whiteville, NCJune 12 bedding

April 17 app June 12 bedding

Silvics Analytic

Oakdale, LAJune 24, 2001

June 12 application June 12 application

Silvics Analytic

Late-Season Bedding

Silvics Analytic

Late-season Bed - Application Timeline

0

1

2

3

4

0 50 100 150 200 250 300 350

Day of year

Lo

cati

on

Before Bed After

Feb 24 May 21 Sept 27 Nov 19

Silvics Analytic

Yulee, FL - Nov 6, 2001 (Nov 19 bedding)

April 19 application June 6 application

Sept 18 application Nov 6 (frost) application

Silvics Analytic

Chopper Application Timing Late-season bedding

Vegetation - June of 1st growing season

0

20

40

60

80

100

Untreat

ed

Befor

e M

ar 2

AprilM

ay

June-

July

August

Sept

Oct

0-3

days

afte

r

Co

ve

r (%

) Herb

Woody

--------------- Before Bed ---------------

Silvics Analytic

Pine Response

Mid-Season Bedding

Silvics Analytic

Pine Volume Index (year 2)Mid-Season Bed – Sandy Soils

0.010.020.030.040.050.060.070.080.090.0

100.0

Feb-Jun 0-3 daysafter

Jun-Aug Nov Untreated(bed only)

Application timing

Vo

lum

e i

nd

ex (

in3)

----

-- B

edd

ing

----

--

44% increase

Silvics Analytic

Pine Volume Index (year 2)Fine Textured Soils – Mid Season Bed

0.02.04.06.08.0

10.012.014.016.018.020.0

Mar-Julbefore bed

0-2 wks Aug-Sep Untreated(Bed only)

Vo

lum

e in

dex

(in

3)

----

-- B

edd

ing

----

--

---- After Bedding----

Silvics Analytic

Pine Response

Late-Season Bedding

Silvics Analytic

Pine Volume Index (year 2)Late-Season Bed - Sandy Soils

0.0

20.0

40.0

60.0

80.0

100.0

120.0

Feb-Jun Jun-Sep Oct-Nov 1-3 daysafter

Untreated(Bed Only)

Application timing

Vo

lum

e in

dex

(in

3 )

----

-- B

edd

ing

----

--

46% Increase

Silvics Analytic

Pine Volume Index (year 2)Fine Textured Soils – Late Season Bed

0.0

2.0

4.0

6.0

8.0

10.0

12.0

14.0

16.0

Mar-Jul Aug-Oct 0-3 wks afterbed

Untreated(Bed Only)

Vo

lum

e in

dex

(in

3)

----

Bed

din

g --

--

------- Before Bed ------

25% increase

Silvics Analytic

Optimal Chopper TimingMid-Season Bed

• June through September at least 3 weeks after bedding

• February up to the day before bedding

• Wait for target species to leaf out.

Silvics Analytic

Optimal Chopper TimingLate-Season Bed

• February through July

• Wait for target species to leaf out

Silvics Analytic

Herbaceous Weed Control Timing

After Chopper Site Prep

Silvics Analytic

HWC after Chopper Site Prep LCP Studies

• Chopper™ Site Prep Rate• 32, 48, 64 oz per acre

• Site Prep Date• July-August• October-November

Silvics Analytic

HWC after Chopper Site Prep LCP

• Herbaceous weed control with Arsenal™ AC (4 oz)+ sulfometuron (2oz)

1) None

2) 1st March

3) 1st June

4) 2nd March

5) 1st March + 2nd March

6) 1st June + 2nd March

Silvics Analytic

Post-plant herbaceous control following Chopper Site prep

• Two timings and three rates of Chopper Site Prep• Different timings of post-plant herbaceous weed

control

Silvics Analytic

Pine response to HWC after Chopper Site Prep

Basic Findings

• 1st year HWC more important than 2nd year HWC

• 1st year HWC important when there is > 20% cover in June

• 1st year HWC is not important when there is less than 10% cover in June

Silvics Analytic

Pine response to HWC after Chopper Site Prep

Basic Findings (continued)

• First Year - March applications were better or similar to June applications

• 2nd year HWC increases pine response if weeds are present and controlled

Silvics Analytic

Pines Responded to Vegetation Control

High Fertility and Tillage were not Substitutes

Silvics Analytic

SI25 75 ft (23m)Year 3 Loblolly Pine Volume Index

0

100

200

300

400

500

600

2X Bed 1X Bed + Chopper

Vo

lum

e i

nd

ex

(in

3) No HWC

First Year HWC

Increasing Level of Vegetation Control

Silvics Analytic

Quality Matters• Chopper was a good base for post-

plant treatments

Silvics Analytic

231 243264

334384

0

100

200

300

400

None 1-March 1-June 2-March 2X

Herbaceous Treatment Timing

Ste

m V

olu

me

Ind

ex (

in3)

June cover = 4%

Green Swamp, NCPine After Three Years

Silvics Analytic

0

20

40

60

80

100

1-June 1-August 1-October 2-June 2-October

Wee

d c

ove

r (%

)

No HWC Yr 2 March HWC

Green Swamp, NCImpact of Year 2 March HWC

Silvics Analytic

August 2 2002

Silvics Analytic

End of 3rd growing season

Silvics Analytic

122

225

188152

259

0

100

200

300

None 1-March 1-June 2-March 2X

Herbaceous Treatment Timing

Ste

m V

olu

me

Ind

ex (

in3)

June cover = 27%

Oakdale, LAPine After Three Years

Silvics Analytic

0

20

40

60

80

100

1-June 1-August 1-October 2-June 2-October

Wee

d c

ove

r (%

)

No HWC Yr 1 March HWC

Oakdale, LAImpact of Year 1 March HWC

Silvics Analytic

LCP Results

• Cover > 20% in June of first year• Apply HWC in first year

• anytime through June• early for best pine response

• Add a second year treatment

• Cover < 10% in June of first year• Apply HWC early in second year

Silvics Analytic

Ivan 2004

Silvics Analytic

Silvics Analytic

HWC combined with Chopper Site Prep - UCP

Silvics Analytic

Chopper Site Prep Treatments UCP

• Chopper Timings• July, October 2002

• Chopper Rates• 32, 48, and 64 oz/ac

Silvics Analytic

HWC Timing UCP4 oz Arsenal + 2 oz Sulfometuron

– None 2003– None 2003 + March 2004

– March 2003 – March 2003 + March 2004

– June 2003– June 2003 + March 2004

Silvics Analytic

Herbaceous Weed Control Timing

First Year March >= First Year June

0

20

40

60

80

100

Ste

m V

olu

me (

in3)

1st Year Tmt

Alabama Arkansas Louisiana

Silvics Analytic

Herbaceous Weed Control TimingFirst Year June >= Second Year March

0

10

20

30

40

50

60

70

Alabama Arkansas Louisiana

Ste

m V

olu

me

(in

3)

1st Year June 2nd Year March

Silvics Analytic

Herbaceous Weed Control TimingTreat 2X with High Competition Levels

0

20

40

60

80

100

March June March June March June

Ste

m V

olu

me

(in

3)

1st Year Tmt Plus 2 nd Year March

+ 34%

Alabama Arkansas Louisiana

Silvics Analytic

Barnett Crossroads, ALChopper as a good base for HWC

0102030405060708090

0 20 40 60 80 100

Average year 1 and 2 total cover (%)

Yea

r 2

pin

e vo

lum

e (i

n3)

Chopper

No Chopper

1st March or 1st March+2nd March

2nd March

No HWC

1st June or 1st June+2nd March

Silvics Analytic

Barnett Crossroads vs. Atmore COMPTotal Height - Year 2

0

1

2

3

4

5

6

7

No Chopper Chopper Site Prep Atmore COMP

Fee

t

Check March HWC-Year 1 Max

Silvics Analytic

Barnett Crossroads vs. Atmore COMPGLD - Year 2

0.00.20.40.60.81.01.21.41.61.82.0

No Chopper Chopper Site Prep Atmore COMP

Inch

es

Check March HWC-Year 1 Max

Silvics Analytic

Chopper Site Prep Improves Quality of 1st March Arsenal + Sulfometuron

Year 2 Pines

0 oz Chopper Site Prep 48 oz Chopper Site Prep

Silvics Analytic

Conclusions

• The historical limitations on Chopper site prep with bedding were too restrictive

• Chopper applications should be done earlier in the year than previously thought

Silvics Analytic

Conclusions

• Chopper site prep combined with the proper HWC treatment regime is a viable operational strategy to achieve yields observed in research studies