Ojai Valley Concerned Scientists

The science behind environmental application of pesticides to stop invading insects 

Ojai Valley Concerned Scientists

Paul Gibbons DVM MS; Heather Mohan MS; Chris Cohen JD;

Nellie Cohen MS; Sarah Otterstrom PhD; Rick Rutherford MD

Ojai’s citrus growers are justifiably concerned and are seeking help to prevent the emergence of Citrus Greening Disease, caused by the huanglongbing bacteria and transmitted by the Asian Citrus Psyllid. The California Department of Food and Agriculture (CDFA) is responding by attempting to stop the psyllid with valley-wide pesticide application. The global scientific community has, however, reached consensus regarding the ineffectiveness of environmentally applied pesticides to stop insect invasions and the CDFA reports that the recommended pesticides will have harmful environmental and health effects. Invasive insect control is feasible and can be successful by implementing safe, proven technologies.1

The effectiveness of pesticides declines over time no matter how strategically they are applied.2,3 Invading insects cannot be stopped by adjusting the frequency, timing, concentration, or variety of pesticides.3 Extensive scientific research proves that environmental application of pesticides does not lead to eradication.1,4

The CDFA published the Statewide Plant Pest Prevention and Management Program Environmental Impact Report
in 2014.5 It states that in addition to a pyrethroid, a neonicotinoid would be applied for quarantine compliance or eradication. It does not provide evidence that pesticides will stop invading pests, and it states that these pesticides will harm people and animals. New research has emerged about the undesirable consequences of these pesticides since the Report was published.6,7,8,9,10 Environmental application of pesticides causes a wide range of adverse biological and ecological impacts that harm global biodiversity, food security, and sustainable development.8,9,10

Science-based Integrated Pest Management will protect our agriculture quickly and sustainably.1,2 One proven method is to enhance biodiversity, rather than weakening our biological defenses by spraying pesticides.11,12 Enriching agricultural regions by planting native flowering plants, for example, encourages a complex assemblage of natural insect species and their associated ecosystem services including crop pollination, natural pest control, and even improved crop production.12,13

We are concerned that CDFA has not informed us about the full plan that will include neonicotinoid application in the near future. We encourage everyone in the Ojai Valley to call (800) 491-1899 and opt out of the pesticide applications. We hope our trusted government officials will put a stop to this verifiably ineffective and harmful initiative. Primum non nocere: above all, we must do no harm.


  1. Liebhold AM, et al. 2016. Eradication of invading insect populations: from concepts to applications. Annual Review of Entomology, 61:335-352.

2. Grafton-Cardwell EE, et al. 2013. Biology and management of Asian citrus psyllid, vector of the huanglongbing pathogens. Annual Review of Entomology, 58:413-432.

  1. Byrne FJ, Krieger RI, Doccola J, Morse JG. 2014. Seasonal timing of neonicotinoid and organophosphate trunk injections to optimize the management of avocado thrips in California avocado groves. Crop Protection, 57:20-26.
  2. Papadopoulos NT, Plant RE, Carey JR. 2013. From trickle to Society of London B (Biological Sciences), 280:20131466.

5. https://www.cdfa.ca.gov/plant/peir/

  1. Botias C, et al. 2015. Neonicotinoid bees. Environmental Science & Technology, 49:12731- 12740.

7. David A, et al applied to crops. Environment International, 88:169-17

Worldwide integrated assessment on systemic pesticides global collapse of the insecticides. Environmental Science and Pollution Research, 22:1–4.

  1. van der Sluijs, et al. 2015.Conclusions of the worldwide integrated assessment on the risks of functioning. Environmental Science and Pollution Research, 22:148–154.
  2. Hladik, et al. 2016. First national-scale reconnaissance of neonicotinoid insecticides in streams across the USA. Environmental Chemistry, 13, 12–20
  3. Letourneau DK, Ando AW, Jedlicka JA, Narwani A, Barbier E. 2015. Simple-but-sound methods for estimating the value of changes in biodiversity for biological pest control in agriculture. Ecological Economics, 120:215-225.
  4. Isaacs R et al. 2009. Maximizing arthropod mediated ecosystem services in agricultural landscapes: the role of native plants. Frontiers in Ecology and the Environment, 7:196-203.
  5. Tschumi M, et al. 2016. Perennial, species rich wildflower strips enhance pest control and crop yield. Agriculture Ecosystems & Environment, 220:97-103.

(published in Ojai Valley News, pg 3, May 6, 2016)