Five Aces Breeding LLC

BIOFUMIGATION

For years we have conducted research on the combined use of rapeseed and solarization to provide the same nematicidal and herbicidal effects as methyl bromide fumigation. The latest work was with Mike Newell at the Wye REC, University of Maryland (pictures at right).  To begin the treatment, plant 10-20 lbs/acre of 'Dwarf Essex' Rapeseed in the Spring. Foster good root growth, increasing the soil sulfur level is helpful (w/ammonium sulfate), but not necessary. In mid summer, when the rape plants are flowering or in immature seed stage AND the soil is moist (very necessary), mow the rape and within 2 hours rototil it in the ground. IMMEDIATELY cover the soil with clear or black plastic by bedding or spreading the plastic the same as tarping chemical fumigant fields with wide sheets of plastic. Make sure the edges are sealed and the plastic is not punctured. Use at least 4 mm plastic because you will leave the plastic in the field for 4 weeks to heat the soil. We have achieved at least 40C (105F) temperatures at 3 to 5 inches deep in the soil. The combination of isothiocyanates released from the decaying rapeseed plants and heat has resulted in killing curly dock seeds and other purposely buried packets of seeds. Not all seeds work but if left undisturbed, the fields look like the pictures at the right (roll over the control and treated pictures). The pictures were taken the next year after treatment; 9 months after the plastic was removed.