experiments to determine the effects of spring chaparral ... · pdf fileexperiments to...

Experiments to Determine the Effects of Spring Chaparral Treatment on Forage Characteristics and

Beef Steer Performance in Missouri

©Dr. Kevin Bradley, University of Missouri

Materials and Methods

• 12, 2.5 acre paddocks; 6 E+, 6 E-

• April 1: 2 ozs Chaparral + 1 qt 2,4-D sprayed on 3 E+ and 3 E-paddocks; 1 qt 2,4-D sprayed on remaining 3 E+ and 3 E-paddocks

• Forage harvests conducted monthly from April – July

Sprayed with 2 ozs Chaparral + 1 qt 2,4-D/A on April 1, Photo Taken May 5


Sprayed with 1 qt 2,4-D/A on April 1, Photo Taken May 5


Influence of Spring Chaparral Application on Total Forage Yields from April - July (Columbia, MO 2010)

0

500

1,000

1,500

2,000

2,500

3,000

3,500

April 13 May 19 June 10 July 9

Yie

ld (

lb/A

)

Harvest Date

1 qt 2,4-D

2 oz Chaparral + 1 qt 2,4-D

© Drs. Sexten, Bradley, and Roberts, Univ. of Missouri

735 a

1846 a

3687a3350 a

540 b

878 b

1600 b 1556 b

*Means within harvest dates followed by the same letter are not different, P<0.05.

Harvest Dates

Herbicide

Treatment

Endoph.

Level April 13 May 19 June 10 July 9

--- Ergovaline + Ergovalinine (ppm)a ---

2,4-D EsterE- 1.83 a 0.18 b 0.08 c 0.02 b

E+ 1.32 a 0.71 a 0.54 b 0.29 a

Aminopyralid+

Metsulfuron+

2,4-D Ester

E- 0.9 a 0.07 b 0.04 c 0.03 b

E+ 1.06 a 0.73 a 0.76 a 0.26 a

a Means within a column followed by the same letter are not different, P<0.05.


Harvest Dates

Herbicide Trtmt April 13 May 19 June 10 July 9

-------------- Crude Protein (%)a -------------

2,4-D Ester 26.0 a 12.1 b 9.2 b 8.8 b

Aminopyralid +

Metsulfuron +

2,4-D Ester

21.6 b 12.7 a 10.7 a 10.3 a

aMeans within a column followed by the same letter are not different, P<0.05.


Harvest Dates


------------------- ADF (%)a ------------------

2,4-D Ester 28.9 a 36.1 a 39.4 a 40.8 a

Aminopyralid +

Metsulfuron +

2,4-D Ester

30.6 a 35.1 b 37.7 a 36.7 a



Harvest Dates


------------------- NDF (%)a ------------------

2,4-D Ester 51.9 a 62.7 a 65.3 a 67.5 a

Aminopyralid +

Metsulfuron +

2,4-D Ester

52.2 a 61.5 b 63.2 a 65.5 a



Influence of Spring Chaparral Application on Forage Grass Seedheads at the July Harvest (Columbia, MO 2010)

0

50

100

150

200

250

300

Tall Fescue Orchardgrass KY Bluegrass Smooth Brome

See

dh

ead

s (#

/m2)

Forage Grasses

1 qt 2,4-D


282 a

111 b

6 a21 a

83 a

60 a

6 a 4 a



Influence of Endophyte Level and Chaparral Treatment on Steer Performance (Columbia, MO 2010)

Control Chaparral P =

Item E- E+ E- E+ SEMa Trtb Endoc Trt x End

Initial wt, lbsd 475.4 469.4 486.1 488.6 10.6 0.19 0.87 0.69

Final wt, lbs 658.3 621.9 639.7 646.8 16.5 0.85 0.38 0.21

ADG, lbs /day 2.24 1.83 2.15 2.08 0.12 0.47 0.07 0.18

Grazing days 82.0 84.0 71.3 76.0 1.3 < 0.001 0.03 0.34

Slick hair, %e 53.3 63.2 56.6 93.2 0.08 0.03 0.13

a Largest standard error of least squared means

b Broadleaf weed control method

c Pasture endophyte presence

d Two day full weight at pasture turnout

e Percent of cattle exhibiting slick hair coat


Influence of Spring Chaparral Application on Steer Serum Prolactin (Columbia, MO 2010)

27

16

21

28

2524

0

5

10

15

20

25

30

May 11 June 8 July 7

Seru

m P

rola

ctin

, ng

/ m

l

Sample date

1 qt 2,4-D 2 oz Chaparral + 1 qt 2,4-D

* Treatment P < 0.05

*


Influence of Endophyte Infection Level on Steer Serum Prolactin (Columbia, MO 2010)

34

28

26

22

13

20

0

5

10

15

20

25

30

35

40

May 11 June 8 July 7

Seru

m P

rola

ctin

, ng

/ m

l

Sample date

E- E+

* **

* Endophyte Level P < 0.05 © Drs. Sexten, Bradley, and Roberts, Univ. of Missouri

Influence of Spring Chaparral Application on Tall Fescue and Grass Weed Density in September (Columbia, MO 2010)

0

10

20

30

40

50

60

Tall Fescue Yellow Foxtail Large Crabgrass Other Grass Weeds

De

nsi

ty (

#/m

2)

Species

1 qt 2,4-D




57 a

13 b

5 b 1 b

33 b

37 a

26 a

14 a

Spring Treatment:

2,4-D Only

Spring Treatment:

Chaparral + 2,4-D

Picture Taken on Sept. 9 ©Dr. Kevin Bradley, University of Missouri

Picture Taken on Sept. 9

Spring Treatment:

Chaparral + 2,4-D

Spring Treatment:

2,4-D Only

©Dr. Kevin Bradley,

Univ. of Missouri

Spring Trtmt. of 1 qt 2,4-D/A

Picture Taken Sept. 9


Spring Trtmt. of 2 ozs

Chaparral + 1 qt 2,4-D/A

Picture Taken Sept. 9


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