Cover Crops for Sustainable Weed Management in a Semi-

Arid Climate Pear (Pyruscommunis) Orchard in Israel

Goldwasser Y1, Abrahams J2, Ogany Y3, Sibony M1 and Rubin B1

1R.H. Smith Faculty of Agriculture, Food and Environment The Hebrew University of Jerusalem, Rehovot 76100, Israel

2Soil Conservation and Drainage Unit, Northern District/Western Galilee Branch, Ministry of Agriculture, Yad

Natan 25212, Israel3Matityahu Research Station, A.R.O, Upper Galilee13860,

Israel

Cover Crop Introduction

• The use of cover crops (CC) is an important component in sustainable agriculture with a wide range of proven benefits in field crops and orchards.

Benefits of Cover Crops

• Prevention of soil and wind erosion

• Enhancement of soil properties (aeration, fertility and moisture retention)

• Increasing of beneficial insects and predators for biological control of pests

• Non-chemical suppression of weeds

Cover Crops suppress weeds by:

• Crop competition

• Shading

• Release of phytotoxic

allelopathic substances

Oat CC emerging in young citrus orchard

Avocado planting into oat CC

Weed management on (herbicides) ,and between (CC) tree rows

Mowing of alfalfa CC in avocado

Mowed and dry oat CC in young avocado orchard

Rhodes grass CC in avocado orchard

Introduction

• In the previous meeting we presented the use of rain-fed dry land CC in orchards in Israel and reported our research in a mature apple orchard in the Upper Galilee of Israel.

Apples 2009

Seeding of CC experiment in an apple orchard

CC experiment in an apple orchard

CC experiment in apple orchard

AIM

The aim of our present research is to study the role of cover crop management on weed suppression in a newly planted pear orchard in the Upper Galilee of Israel.

Pears 2009

Materials & Methods Log

2008Nov. 19 - Building of ridgesNov. 20 - Disking of ridgesNov. 27 - CC seeding2009Jan. 05 - CC and weed estimationFeb. 15 - Pear tree plantingMar. 11 - CC and weed estimationMay 03 - CC and weed estimation

Hand spray weeds in Standard management treatmentsApr. 19 - CC and weed estimation

Mowing of all controlsJun. 17 - CC and weed estimationJul. 29 - CC and weed estimationAug. 27 - CC and weed estimation

1. Natural weed cover- Mowing2. Standard management- Herbicide spraying and mowing3. Oat CC 4. Oat CC + tree row mulch5. Oat+Vetch CC6. Oat+Vetch CC + tree row mulch7. Triticale8. Triticale+ tree row mulch

4 Replications3 CC strips, 30 m long, 3.5 m wide

Materials & Methods Treatments

Results

Cover Crop Coverage Estimation

0

20

40

60

80

100

120

Triticale Triticale+ Oats Oats+ Oats/Vetch Oats/Vetch+

Co

ve

r C

rop

Es

tim

ati

on

(%

)

05 Jan 11 March 19 Apr 17 Jun 29 Jul 27 Aug

Weed Coverage Estimation

0

20

40

60

80

100

Standardmanagement

Natauralcover

Triticale Triticale+ Oats Oats+ Oats/Vetch Oats/Vetch+

We

ed

Co

ve

rag

e E

sti

ma

tio

n (

%)

05 Jan

11 March

19 Apr

17 Jun

29 Jul

27 Aug

Weed Inventory Winter Weeds

• Malva nicaeesis• Sinapis arvensis• Silybum marianum• Ranunculus arvensis

• Senecio vernalis• Lamium amplexicaule• Avena sterilis• Hordeum glaucum

Weed Inventory Summer Weeds

• Polygonum equisetiforme• Convelvelous arvensis• Ecballium elaterium• Chrozophora tinctoria• Amaranthus retroflexus• Amaranthus hybridus• Amaranthus albus

• Lactuca serriola • Chenopodium vulvaris• Solanum nigrum• Plantago lagopus • Conyza arvensis• Tribulus terrestris• Portulaca oleracea

28 October 2008

27 November 2008

CC seedingCC seeding

27 Nov. 2008

03 May 2009

03 May 2009

24 May 2009

17 June 2009

3 May 2009

17 June 2009

29 July 2009

27 August 2009

Oat+Vetch

March 2009

Natural cover and standard management

19 April 2009

03 May 2009

Oat

St. Jonathan (1.80 m) and the oat beard

3 May 2009

Triticale

April 19 2009

April 19 2009

Oat+vetch

Natural cover and standard management mowing

April 19 2009

Oat+Vetch

May 24 2009

Oat+Vetch

17 June 2009

Triticale

17 June 2009

17 June 2009

OatOat

17 June 2009

Oat+Vetch

Triticale

29 July 2009

29 July 2009

Oat+Vetch

29 July 2009

Triticale

27 August 2009

Oat+Vetch

Conclusion

• Cover crops suppressed weed infestation in a young pear orchard.

• Cover crops reduced both the number of weed species and the number of weeds within a weed specie.

• In this first year Cover crops study, results show that the combination of Oats and Vetch were the most efficient in weed suppression.

Future research

• Long term monitoring of the development of CC and weed species and populations.

• Evaluation of the benefits of throwing CC mulch on tree rows.

• Determining the separate roles of shading, crop competition and allellopathy of the different CCs on weed suppression.

Acknowledgments

The Matityahu Experiment Station staff for maintenance of the field experiment