New Ontario Lawn Pesticide available in Spring of 2012 – Phoma Macrostoma – Scotts Company

Just like with Sarritor, There may be limited availability of this product for 2 to 3 years as manufacturing may be an issue.  Sarritor was only available to Weedman and Dr. Green initially.

This is the final hope for the remaining 50 percent of Ontario Lawn Care Operators.  

FYI:  (The Ministry of Environment has licensed 50% less Pesticide Operators in Ontario since the 2009 Pesticide Ban)

No IPM required, No Spot Spraying needed.  3-7 Lbs of Granular product per 1000 sq feet.  Controls a few weeds and suppresses a few more.  Blanket apps are back and in a granular form.  2-3 apps a year.  PRE and POST emergence properties in this product.  (Thats 7 to 8 apps a year for some members of the Landscape Ontario Commodity Group, they follow their own beating of the drum when it comes to rules.)

What better way to test a product than on your own customers properties.  Do you think they can handle another failure?

2  factors that need to be considered are :

– Shelf Life

– Cost

Karen Bailey has indicated in her research that overly wet conditions can wash away this product and possibly move it off target.

On December 15, 2011, the three products, containing the new active ingredient Phoma macrostoma strain 94-44B were classified based on the recommendation of the Ontario Pesticides Advisory Committee as shown below: Scotts EcoSense Weed-B-Gon Ready To Use Lawn Weed Control Herbicide (Reg.No. 30132) was placed in Class 5. Scotts EcoSense Weed-B-Gon Ready To Use Lawn Weed Control (Reg.No. 30134) was placed in Class 6. Scotts Phoma P Commercial (Reg.No. 30136) was placed in Class 3. The Class 11 list is being updated to include the new active ingredient Phoma macrostoma strain 94-44B.


Abstract: Phoma macrostoma 94-44B was evaluated against 94 plant species in 34 botanical families, of economicallyimportant agricultural, horticultural and ornamental species, as well as target and nontarget weeds.Fifty-seven species from 28 families were found to be resistant to P. macrostoma, while 38 species from 12families, six of which also contained resistant species, were found to be susceptible. Those families comprisingboth susceptible and resistant species included the Asteraceae, Brassicaceae, Fabaceae, Lamiaceae,Plantaginaceae and Rosaceae with the foremost three containing the largest numbers of susceptible species.P. macrostoma was pathogenic to many dicotyledonous plant species, but nonpathogenic to monocots.Commercial applications for weed management in turfgrass, agriculture, horticulture and forestryseem probable, while domestically management of weeds in lawns, transplanted ornamental and annualflowering species may provide alternative markets.

Outstanding Health Canada Registration Requirements:

To confirm the manufacturing methods and quality assurance for final commercial production, the registrant is required to provide confirmation of production methods, a five batch analysis for microbial contaminants and confirmation of product guarantee from production lots of Scotts EcoSense Weed-B-Gon Technical Bio-Herbicide and its associated end-use products from the manufacturing sites.

Data are required from additional field trials in which the efficacy of Phoma macrostoma strain 94-44B, applied pre-emergence at 16 g a.i./ha, is evaluated to confirm its efficacy for season-long control of the following weeds: chickweed, broadleaf plantain, common ragweed, wild mustard and English daisy.

The outstanding product characterization and value information must be submitted to the PMRA by September 1, 2014.


Executive Summary:

The bioherbicide was able to control dandelion (68%), field bindweed (60%), annual sow thistle (97%), and wild mustard (82%). The least effective rate for Canada thistle was 0.7X the standard agricultural rate and for wild mustard it was 1.0X. There was also some reduction in perennial sowthistle, smart weed, Canada thistle, false cleavers, hemp nettle, and brassica volunteers but reductions were only from 25-50%. The bioherbicide had no effect on stinkweed, lambs quarters, and wild oat. Weed control of the various species was site dependent which was likely due to different moisture conditions and weed pressure. Soil moisture is a key requirement for the bioherbicide to work. Yet the bioherbicide was able to survive in dry soil for nearly 4 weeks before favorable conditions occurred and then it provided effective control of late-emerging wild mustard seeds. The bioherbicide worked best to control emerging seedlings and was less effective on well established weeds using a single application. Post-emergent application of the bioherbicide granules was more difficult when the crop was etablished. It is necessary to get even distribution of the bioherbicide over the surface otherwise control becomes more variable. To make the bioherbicide work better, there needs to be more work done on the application method to get even distribution of the product, the time of bioherbicide application relative to weed emergence, the impact of environmental conditions on efficacy, and multiple trials at several sites to assess the consistency of response for specific weeds.