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 2008 Nov Building of ridges Nov Disking of ridges Nov. 27- CC seeding 2009 Jan. 05- CC and weed estimation Feb Pear tree planting Mar CC and weed estimation May 03 - CC and weed estimation Hand spray weeds in Standard management treatments Apr. 19- CC and weed estimation Mowing of all controls Jun. 17- CC and weed estimation Jul. 29- CC and weed estimation Aug. 27- CC and weed estimation

1.Natural weed cover- Mowing 2.Standard management- Herbicide spraying and mowing 3.Oat CC 4.Oat CC + tree row mulch 5.Oat+Vetch CC 6.Oat+Vetch CC + tree row mulch 7.Triticale 8.Triticale+ tree row mulch 4 Replications 3 CC strips, 30 m long, 3.5 m wide Materials & Methods Treatments

Results

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 seeding 27 Nov. 2008

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

Oat+vetch

Natural cover and standard management mowing April

Oat+Vetch May

Oat+Vetch 17 June 2009

Triticale 17 June 2009

Oat

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

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