|DOLL, D - University Of California - Cooperative Extension Service|
|QIN, R. - University Of California|
|Rana Dangi, Sadikshya|
|HANSON, B.D. - University Of California|
Submitted to: Almond Industry Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 12/8/2015
Publication Date: 12/9/2015
Citation: Gao, S., Doll, D., Qin, R., Rana Dangi, S., Hanson, B., Gerik, J.S., Browne, G.T., Wang, D. 2015. Minimize emissions and improve efficacy with low permeability tarp and deep injection in soil fumigation. Almond Industry Conference Proceedings. p.57.
Technical Abstract: Soil fumigation targets high pest control efficiency and low environmental impact. Earlier field data show that most fumigated treatments provided 100% kill for plant parasitic nematodes in the soil above 3 ft depth, but not below due to insufficient fumigant delivery. A fumigation trial was conducted in December 2014 at an almond orchard to be replanted in Ballico, CA. A deeper injection was tested for potential improvement on fumigant (Telone C35®) delivery to deeper depth and effects on emissions. Treatments included two injection depths: regular 18 inch injection depth and a deeper (28 inch) injection depth with full rate, 2/3 rate, and non-fumigated controls, and three surface sealing methods: no tarp, standard polyethylene (PE) tarp, and low permeability tarp TIF. Emissions and fumigant movement in soil were monitored. Soil samples from 0 to 5 ft soil depths four weeks after fumigation were examined for survival of parasitic nematodes. Data demonstrated that the deeper injection facilitated fumigant movement to below 3 ft depth in the soil, which was Delhi sand. The TIF was confirmed to give the lowest emissions by most effectively retaining fumigants under the tarp. Also significantly lower emissions were measured from non-tarped soil due to precipitation received during the trial compared to the PE tarped. Except for a single surface soil sample, all fumigated treatments resulted in no survival of parasitic nematodes down to 5 ft depth in this coarse textured soil. Young almond trees were replanted after tarp removal and tree growth is being monitored to determine long term fumigation treatment effects.