UPDATE: Use of Pyrethrins and Neem Oil
|Note: This page was posted Aug. 20th, 2007. The situation currently is largely unchanged except that more of these products are being used and pyrethrins/pyrethroids are now the major cause of pesticide incidents in the domestic environment; also it has been proposed to add FeHEDTA herbicides to the pemitted materials - DP, March 2, 2011.|
Cautious use of pyrethrum on a limited scale, e.g., for rose chafers, is probably not very problematical. However, the PMRA approval for use of a pyrethrin product on chinch bug, combined with pyrethrins being allowed under the Pesticide By-law, opens the door to unrestricted, large scale use of pyrethrins on lawns by individuals and lawn care companies in municipalities where pesticide by-laws have been passed. This could pose significant risks to human health and environment. The same concerns apply to widespread use of pyrethrin products for other lawn pests, e.g., various grubs.
What to do?
In the shorter term, the PMRA approved pyrethrin product at least provides an alternative to carbaryl. Thus no permits for use of carbaryl to control chinch need now be issued.
On the other hand, widespread use of pyrethrins could pose significant health and environmental hazards, and be a disincentive to adopting truly sustainable solutions such as those outlined on this site and that have been promoted by past and present agencies responsible for administering the Pesticide By-law in HRM (Clean Nova Scotia and Ecology Action Centre).
Under PMRA regulations, neither homeowners nor pest
control professionals are allowed to use insecticidal
soap to contol chinch bug; the PMRA seems to
unofficially tolerate use of the less efficaceous and
highly variable household soaps by homeowners
but not by professionals.
In that context, pyrethrins should be Restricted as they are under certified organic practices, and be used only under exceptional circumstances and with a permit. See Permitted Materials on this website for more details about classification of pesticidal materials, and a Proposal for aligning the Pesticide By-law more closely with OMRI/CGSB organic standards.
Also, it remains for the PMRA to register a pure insecticidal soap product(s) for control of chinch bug (as in the U.S.), which is needed to provide a much safer alternative to carbaryl than the pyrethrin product. Insecticidal soap products are registered in Canada for control of a number of pests but, for reasons unknown in the public domain, these do not include chinch bug; further, the PMRA is elusive and ambiguous on the issue of use of household soaps to control pests, except to say that professonal pest control companies and personnel may not use them.
See Legality of Using Soap to Control Chinch Bug (in Canada).
The PMRA has NOT approved neem oil for control of pests in Canada, but seems to be closing its eyes to promotion of neem oil as an agent to "optimize the health of your lawn". That is how a flyer distributed in HRM by a major lawncare franchise describes their "Neem Oil Treatment". It "introduces a variety of plant extracts that will help optimize the health of your lawn heading into the hot, dry summer months when environmental stresses can wreak havoc on your lawn.. helping to prevent plant damage resulting from insects and disease occurring through this period." The same flyer states prominently "This application does not require a permit from the Halifax Regional Municipality".
Neem solid in an HRM gardening supplies
outlet as a foliar treatment (May '07). Similar
products are sold in the U.S. and other countires
I received this flyer on Aug. 14 when a friend and I were checking the level of chinch bug damage in a neighborhood where there had been extensive chinch bug damage in 2003. We stopped to talk to a franchise agent who had just finished spraying a lawn. "Fertilizing the lawn?", I asked. "No, controlling chinch bug", he said. We asked how that was done.. "Neem", he said, and gave us the flyer.Neem oil is also available in some retail outlets; here is how one outlet describes one product: "Target Neem Oil can be used any time during the growing season to enhance plant appearance and give them a healthier look. Use on indoor tropical plants and greenhouse use year round. In addition to its use as a leaf shine many people have observed its use as an insecticide, especially for the control of lily beetle. "
In one sense we can hardly complain about the PMRA encouraging less toxic materials through some type of benign neglect , and their use by lawn care companies that have actively opposed the development of pesticide by-laws in the past is progressive on their part. But then why not allow neem products to be registered as pesticides, so we can call a spade a spade and provide the appropriate information for pest control and properly regulate their use?
The process by which the PMRA is dealing with these "alternative" materials appears very ad hoc; it is definitely ambiguous and confusing, viz. the soap issue (cited above) and neem oil. Another vaguely defined area relates to "organic herbicides". Corn gluten is registered as a herbicide (and has a PCP number), but not beet extract products which are being used by at least one lawncare franchise. It is very unlikely that a large franchise would not clear use of such products with the PMRA. So the question has to be asked: when and how is the decision made by the PMRA to require registration in one case (e.g., for corn gluten) but not in another (e.g., beet juice), and what are the conditions under which the use does not contravene the Pest Control Products Act? It is in the interest of everyone to know that and to benefit from new alternative materials, not just the lawncare franchises!
Interestingly, there was almost no evidence of chinch bug damage in this neighborhood in mid-Aug 2007, in marked contrast to the situation on 2003 (see photos). It remains to be determined whether use of neem, or pyrethrins, or the generally rainy weather this summer or improved cultural practices in the neighborhood, or all of those factors, are involved.