# City of Davis

Integrated Pest Management Program

2008 Annual Report

Submitted to the Natural Resource Commission on March 23, 2009 Prepared by: Martin Guerena, IPM Specialist and

John McNerney, Wildlife Resource Specialist.

2008 Integrated Pest Management Report 1

## 1.0 Overview

The purpose of this report is to provide th e Natural Resource Comm ission (NRC) with an overview of City efforts to control pests in a variety of settings in and around the community. As outlined in the report, staff employs a numbe r of methods to achieve the functional, public safety, and aesthetic vegetation control standards that have been established for City managed areas. The report also reviews th e policy decisions that shaped th e City’s current approach to weed management and provides analysis of severa l factors that influenc e program decisions.



## 2

. 0 Introduction and Background

In the 1980’s the City of Davis’ pesticide us e was similar to other cities and ag ricultural operations. Much of the maintenance of park, gr eenbelts, landscaping, bike paths, streetscapes and open space consisted of scheduled applications of fertilizers and pesticides. The pesticides used were a mixture of Category I (Dange r), II (Warning) and III (Caution) compounds.

In 1989 the city established an Integrated Pest Management (IPM) prog ram where new methods of managing public landscapes we re imposed, these included:

• First IPM Policy developed by the Parks and Community Services department.

• First IPM specialist hired by the City of Davis.

• Issuing written pesticide recommendations.

• Consolidate and centralize pesticide storage in upgraded facilities.

• Cooperating with UCD in experimenting and utilizing beneficial insects and other practices.

• Minimize toxic pesticide use.

• Increased staff training and education on IPM.

Seven years later in 1996, the city council approved the creation of an IPM task force which was made up of UCD experts including IPM speci alist, entomologist, weed scient ist and plant pathologist as well as representatives of the US Forest Service and priv ate landscapers. The task force primary goals were

to:

• Reduce the pollution load of pesticides within the City of Davis

• Increase awareness and use of IPM by citizens via education & outreach

• Provide recommendations that will as sist in improving the IPM program

• Reduce the use of pesticides within the city, by businesses and retail operations via technical assistance and education programs

The IPM task force report was completed in 1998 with the following conclusions:

• Identify the conditions causing pest problems.

• Devise ways to change conditions so as to discourage reoccurrence of pests.

• Select least hazardous combination of strategies to control the pests.

• Conduct on going training and IPM advisory assistance.

2008 Integrated Pest Management Report 2In 1998 the Environmental Protection Agency (EPA ) awarded the City of Davis a PESP (Pesticide Environmental Stewardship Program) Grant Award for IPM Education. The IP M demonstration signs and “garden friendly” posting thr oughout the parks and greenbelts ar e remnants of that funding.

The IPM program came under review in 2000 by the Na tural Resources Commissi on with the following

recommendations:

• Continue reducing category II applications.

• Continue posting for pe sticide applications.

• Continue the native grasses area conservation.

• Study the IPM coordinator option.

• Continue training efforts with citizens and staff.

2000 – 2007 Environmental resource supervisors (Ope n Space), wildlife resource specialist and the environmental compliance coordinator ove rsaw and reported on the IPM program.

2001 Local interest group requested the County Agri cultural Commissioner to investigate herbicide use and reporting within the ci ty. The investigation revealed only minor deficiencies with recordkeeping due to the size of the three department s. Each department would maintain records and

coordinate IPM activities.

2005 Public Works develops an IPM plan, which includes:

• Less reliance on chemical controls.

• Maintenance of positive relations between the city’s departments, regulatory agencies, and concerned public entities.

• Balancing weed controls within depa rtmental economic constraints.

2007 Citywide pesticide use policy de veloped and IPM specialist hired.

2008 IPM Policy developed.

The citywide IPM Specialist position was sta ffed in the fall of 2007. The IPM Specialist coordinates citywide IPM activities, evaluates a nd trains field staff on alternative pest control methods, and keeps records for all departments. The position is currently funded between Parks & General Services (PGS) and P ublic Works (PW) departments.

Parks maintenance personnel in th e PGS department as well as c ontractors are involved in pest control activities, mostly weed control thr oughout the parks, greenbelts, open space, and landscaped street medians. Public Works has thre e divisions involved in pest control activities. The Wastewater Treatment Plant (WWTP) pe rsonnel maintain the grounds around the plant, lagoons, overland flow, associated open space and treatment wetlands. Challenges posed here are maintaining the function of the overland fl ow process by controlling broadleaf weeds like curly dock, mustards and perennial pepperweed. The wetlands are constantly threatened by the spread of invasive weeds such as star thistle ( Centaurea solstitialis ) and perennial pepperweed ( Lepidium latifolium ). The transportation division maintains streets, roadsides, bike paths, and the old landfill/ pistol range site. Most weed control is done by a contractor who treats problem roadsides and non-landscaped traffic medians with he rbicides in the late fall. The Collections division is in charge of mainta ining stormwater flow within dr ainage channels, right of way

2008 Integrated Pest Management Report 3access and is responsible for maintaining the sa nitary sewer system. Current pest control response is dictated by the results of pest population monitoring by field staff. Monitoring results are compared to action th resholds. Action thresholds incl ude functional impairment, fire hazard, and aesthetic degradation. Functional impa irments are infestations that impair the operation of a City facility, program, and/ or ob jective. Stormwater conveyance, for example, may be inhibited due to dense gr owth of invasive plants. In some instances aggressive pest species such as yellow starthistle ( Centaurea solstitialis ), and perennial pepperweed ( Lepidium latifolium ) are treated prior to threshold realizatio n to prevent rapid co lonization and habitat damage. Dense weed growth on City property, adj acent to private or public structures, creates a

fire hazard. Weed infestations th at occur in parks, bike or sidewalk paths, and road medians are

considered hazardous and/ or of poor aesthetic value.

The following section presents the 2008 calendar y ear activities with rega rds to the City’s IPM Program. IPM policies apply to all City department s. However, this report details P&CS and PW activities, as they have primar y pest management responsibility.



## 3.0 Program Achievements in 2008

3.1 IPM Innovator Award

This award from the California Department of Pesticide Regulati on (DPR) is given to organizations recognizing their efforts to reduce ch emical pesticides via cu ltural, biological and mechanical control methods. Throughout the y ears DPR has given out more than 100 IPM

Innovator awards to honor Califor nia organizations that emphasi ze pest prevention, favor leasthazardous pest management, and share their succe ssful strategies with others. The awards are part of a comprehensive, reduced-risk pest mana gement strategy aimed at homes, schools, farms,

and the environment.

3.2 Our Water Our World (OWOW) Program

The OWOW program conti nued to be implemented at three pesticide retail stores in Davis (Davis Ace, Redwood Barn and Nursery, and Longs Drugs) in 2008. This program provides “Less Toxic” fact sheets and shelf tags set adj acent to pesticides. In addition to the written materials, store employees are given training regarding what products are environmentally conscience alternatives for pest control.

3.3 IPM Comic “The Exterminator”

The IPM and Stormwater Pollution Prevention Pr ograms partnered to create a comic book for youth and young at heart that demonstrates leas t toxic approaches to managing urban household
pests.

2008 Integrated Pest Management Report 43.4 Alternative Pest Control Practices

Staff continued to work with alternat ive pest control methods including:

• “Green pesticides” : products derived from soap, acetic acid, herbal oils or microorganisms.

• Biological control : use of predatory organisms such as nematodes for grub controls on ball field turf, and promoting bird s-of-prey to eat pest rodents.

• Mechanical control : removal of weeds by “weed wackers” , tractor implements or hoes.

• Grazing : use of goats and sheep at Mace Ranch wildlife habitat.

• Mulching : use of wood chips to cover open ground, smothering weeds.

• Sheet Mulching : mulching but with cardboard or weed cloth barriers.

• Flaming : use of propane flamers to burn down broadleaf weeds.

• Solarization : use of clear plastic du ring the summer to pasteurize the soil, killing or debilitating most weed seeds.

• Flooding : use of flooding in the wetlands to deprive weeds of air.

3.5 City of Davis IPM policy incorporati ng Pesticide Hazard Avoidance and Exposure Reduction (PHAER) zones.

The city IPM Specialist revised the citywide IPM policy with the incorporation of the Pesticide Hazard and Exposure Reduction (PHAER) zones progr am. This strategy gives structure to the implementation process of the IPM policy in parks and greenbe lts by allowing supervisors the needed flexibility in their management options and informing the citizens about the general level of pesticide hazard present on a site-by-site basi s. These zones are designated as Green, Yellow and Special Circumstance Zones, with Green Zone s providing the lowest potential for pesticide hazard and exposure. Each Zone has a corr esponding pesticide list determined by existing toxicological data. Mace Ranch a nd Central Park are the first pa rks in the city to have the PHAER zone program implemented. Contract ed landscape maintenance and pest control companies have been presented with this program and are expected to abide by it. Staff training of contracted company employees regarding th is policy and project has been conducted in Spanish.

3.6 City partnership with the UC Davis Ar boretum and volunteers on the Central Park demonstration garden project.

In 2007, city staff from both PW and P&GS part icipated in the design and development of the Central Park demonstration garden project. This project demonstrat es the use of drought tolerant and native plants, zone irrigation, and alternative pest control. Th e city continues to collaborate with the arboretum with public outreach events related to the garden.

2008 Integrated Pest Management Report 53.7 PW and PGS field staff received Pesticide Applicat or Certificates

Developed and conducted preparatory courses fo r City of Davis staff seeking Qualified Applicators Certificates. Lead a class once a week for a month before the scheduled exams covering materials such as pesticide safety, la ws and regulations, and IPM practices.

3.8 City of Davis IPM Web Site

Online information on the City’s IPM program in cluding access to the city’s IPM and pesticide use policies, details on how to deal with local pest s, links to other useful sites as well as details on the Pesticide Hazard and Exposure Reduction (PHAER) zones program. The Exterminator

comic is also available to download.



### 4.0 Alternative Pest Control Activities

Several alternative pest control methods were co ntinued in 2008 to reduce reliance on pesticides and meet IPM objectives.

4.1 Weed management

Mechanical Removal : Mowing, weed trimming, and tilling con tinued to be utilized by City crews to control weeds and stimulate native gr ass growth. Extensive mowing and tilling were used in 2008 at the WWTP, Davis Wastewater Treatment Wetlands (Wetlands), park and greenbelt facilities and various open space areas. Some of these e fforts resulted in higher costs associated with labor and equipment maintenance, but helped to reduce herb icide use. Feasibility of future reliance on these methods may be reduced due to budgetary constraints.

Hand Removal : Seasonal employees and volunteers were utilized at the WWTP, Wetlands, and community garden sites to pu ll weeds from around landscaping and native plant restoration

areas. Similar to mechanical removal this contro l method increases labor. Cuts in City labor force could reduce feasibility of this method; however, volunteer service may help to reduce

costs.

Flooding : Water level management continued to be effective at controlling weeds and Canada goose nest density at the local st ormwater detention basins and the Wetlands. Water levels were

raised onto the seasonal benche s during winter months and allowed to remain into spring.

Rx Burning: Prescribed fire was used at the Wetla nds to stimulate native grasses and reduce weed seed production.

Grazing: Livestock grazing is utilized at the Mace Ranch Community Park habitat area and Yolo County Grasslands burrowing owl preserve to me et burrowing owl habitat objectives. Livestock are free ranged for 2 months to meet this goal.

2008 Integrated Pest Management Report 6Use of Native Vegetation in New Landscaping Projects : The City contin ued to utilize native trees, shrubs, and grasses in municipal landscape projects. Native plants were included in the landscaping of the new Central Park Garden. Native grasses were seeded along several pond

benches at the Wetlands. Once established native vegetation can successfully out compete weed species. This helps to reduce weed manageme nt activity. Native plan ts also require less irrigation, which reduces risk of offsite movement of fertilizers or pesticid es into the stormwater system. The use of native plantings increases th e costs of the project. Reliance on the use of native plants may be reduced due to budgetary constraints.

Weed Habitat Removal : P&GS landscape contractors and park field staff continued to maintain mulch around landscaped areas. Mulch helps to smother weeds and reduces the need for

fertilization and water.

Proper Timing of IPM Control Activities : Continued monitoring of weed development led to proper timing of weed management. Growth stage of weeds often dictates type of management

method to be used.

Organic Herbicide: Trials with these products continue be tested and are showing promising results. Concentrated acetic acid (vinegar) in co mbination with a soap based herbicide or with

the herbal oil based herbicides have shown promise in burning down annual broadleaves. This is encouraging for areas that are sensitive to conventi onal pesticide use due to human and pet exposure or wildlife habitat. Work will continue in other areas as well, especially those that relate to water quality issues.

Weed Flaming: Propane flamers are utilized when conditions of high humidity reduce the options for other forms of weed control. Th is technique is effective on small, recently germinated broadleaf weeds.

4.2 Other Pest management

City Stormwater Basins and Wetlands Pest Control: Mosquito control within the local

stormwater retention basins and at the Wetlands continue d to be through water level manipulation and biological cont rol only. Bringing water levels down during the peak mosquito production time allows predatory species to acce ss larvae. All areas continued to support sufficient populations of pr edatory mosquito fish ( Gambusia affins ).

Rodents were controlled in a couple of parks by placing secure baiting stations in strategic areas. Results were achieved in a couple of weeks. Mu sk rats and ground squirr els within stormwater basins, WWTP, Wetlands and parks were removed as needed via both no n-lethal/non-toxic live trapping and least toxic baiting. The city has al so implemented a barn owl nest box installation program in parks and neighborhoods. The program aims to increase the population of natural predators to help regulate rodent pest species within the city planning area.

Hackberry tree aphid control on some parks and park ing lots are preformed using imidacloprid to control the aphid and thus the pr oduction of honeydew. This product is also occasionally used to

2008 Integrated Pest Management Report 7control beetle grubs on the fiel ds at Playfields Park. Pred atory nematodes are used as a preventative on these grubs but if population thre sholds are exceeded the insecticide is used.

Sewer line root control is conducted by the Co llections division of PW as part of a comprehensive sanitary sewer maintenance program. This regulatory mandated program aims to prevent sanitary system overflows or system failure by controlling, among other things, root intrusion. Root control includes, but is not lim ited to, the use of Vaporooter, a class one category pesticide. Prior to 2008, this product was not included in pesticide use reporting due to a misunderstanding of product registra tion. Since becoming aware of this error, changes have been made to include the product in pesticide reporting and ensure that it is used in accordance to the City’s pesticide application polic y. Mechanical methods as well as alternative herbicides will be

evaluated to determine the most efficient and sa fe way to control root intrusion in the sewer

lines.



## 5.0 Public Outreach and Education

The City continued to provide publ ic outreach and education on pest icides using several forms of communication. City staff was also educated on weed and pest control techniques and current

trends in IPM. Outreach and education efforts included:

• Development of City of Davis’ IPM website.

• Development of IPM comic “The Exterminator”.

• Notification of City herbicide application activities in parks an d greenbelts via the

Pesticide Hotline.

• Tips and alternatives to pesticide use pr ovided in the annual PW sponsored “Utility Connections” and citywide “Focus” newsletters.

• Distribution of IPM educational literature at community even ts. The city partnered with the Master Gardener Program to provide fr ee advice at the Celebrate Davis event. The

Davis Green Home and Garden Expo provided opportunities to di splay the city’s effort at least toxic pest control. Ta bles featured the OWOW program, bat and owl boxes as well as pamphlets and handouts on our pest control programs among other things.

• Periodic presentations at local schools regarding stormwater quality including tips and alternatives to pesticide use.

• Presentations on least toxic pest control at the community gardens, Central park garden

and the Mace Channel Herb Garden.

• City sponsored annual Horticulture Pest Control Seminar where continuing education units are available to city staff and other pest control professionals from the school district and surrounding communities.

• Pesticide safety training for City field staff.

• Attendance at IPM conferences by department al staff involved with IPM coordination.

• Annual presentations to the city counc il and citizen advisory commissions.

• Encouraging local pesticide venders to participate in the OWOW program.

• Use of positive posting at locati on where alternatives to chemical pest control were in

use.

2008 Integrated Pest Management Report 8

## 6.0 2008 Pesticide Use

TABLE 1: Summarizes pesticide use 1 by product for calendar year 2008 with comparison to 2005 through 2008

.

Product EPA Category 2005 Use 2006 Use 2007 Use 2008 Use Round-up [3] III 101 gal 100 gal 180 gal 127 gal Vaporooter [7] I No data No data No data 19.5 gal

Surflan As III 0 gal 0 gal 0 gal 0 gal

Prepair III 0 lbs 7.7 gal 0 gal 0 lbs

Atrimec III 13.5 gal 0 gal 0 gal 0 gal Safer Soap III 0 gal 2.7 gal 6.1 gal 0 gal

Garlon 4 III 3.7 gal 20.8 gal 22 gal 1.1 gal

Goal [1] II 17.8 gal 100 gal 180 gal 21.2 gal Manage III 2.2 lbs 0.006 lbs 0.9 g 1.3 g

Turflon III 1.1 gal 0.2 gal 0.03 gal 3.1 gal

Transline III 0.26 gal 1 gal 0.3 gal 1.3 gal

Telar III 10.8 oz 17 oz 36.1 oz 8.7 oz

Fusilade III 0 gal 0.02 gal 0.06 gal 0.25 gal Aquamaster [8] III 13.3 gal 1.5 gal 3.9 gal 1.8 gal

Merit III 8.4 gal 8.5 gal 0 gal 0 gal

Direx 4L III 6.8 gal 2.5 gal 4.7 gal 0.5 gal Snapshot III 4825 lbs 2922 lbs 3325 lbs 5900 lbs

Shark III 0 gal 0.03 gal 0 gal 0 gal Clarity [2] I 1 gal 2.6 gal 1.1 gal 0.7 gal

Weedar 64 [2] I 5 gal 1.9 gal 3.4 gal 2.2 gal

Barricade III 0 gal 0.2 gal 5.2 gal 2.3 gal

Greenmatch [6] III 0 gal 0 gal 1.3 gal 0 gal

Zenith 75WSP III 0 gal 0 gal 0.3 gal 0.4 gal Sedgehammer III 0 lbs 0 lbs 3.8 g 104.3 g Payload III 0 gal 0 gal 2.7 gal 2.5 gal

Pendulum III 0 gal 0 gal 0 gal 500 lbs

Scythe II 0 gal 0 gal 0 gal 1.3 gal

Landmark III 0 gal 0 gal 2.3 gal 0.9 gal

Milestone III 0 gal 0 gal 2.9 gal 0.5 gal

Notes: [1] Used primarily in native grass re storation sites with limit ed public access (e.g. outlying open spaces and Davis Wetlands). Includes Goaltender. [2] Use of this material is restricted to the Overland Flow process of the Wastewater Treatment Plant. Public access is prohibited. [3] Combined Round-up products (Ultra, Pro, Weather max). [6] Organic herbicide [7] Used in sewer lines to remove intruding roots [8] Includes Rodeo, the old name for Aquamaster (aquatic glyphosate formulation)

1 Includes City contracted pest control applications.

2008 Integrated Pest Management Report 96.2 Comparison of 2008 Usage to 2007 Usage

Use of liquid products in 2008 was 45% lower th an in 2007 (416 gallons vs. 187 gallons). Solid products were used more (56%) in 2008 th an in 2007 (5900 pounds vs. 3325 pounds). The data suggests that in years where pre-emergence herbic ides increases, post emergence use decreases. This year the use of pre emergence is lower in th e first two months and is expected to reduce for the rest of the year. The use of post emergence he rbicide is also expected to decrease somewhat because of the increased use of “green herbicides” as a substitute in some situations.

6.3 Pesticide Use by Management Area

The City currently manages 1736 acr es of land that are subject to IPM. This acreage is divided into 6 major management areas including: Park s, greenbelts, and streetscapes (528 ac.); Open Space (548 ac.); Transportation System (30 ac.): Stormwater System (101 ac.); Wastewater System (489 ac.); and Facilities (40 ac.). The 6 major areas are further divided into sub areas. Table 3 details the sub areas and offers a per centage of total annual use by major area,

Table 3: Percentage of total pesticide use by major area in 2008 with 2007 comparison. Major Area Sub Area Acres % of Total Use 2008/

2007 Parks, greenbelts, and streetscapes 528 46/ 60

Open Space 548 2/ 2 Agricultural buffers

Restoration areas Mitigation habitat

Transportation System 30 7/ 8

Street median and Shoulders

Sidewalks

Bike paths

Stormwater System 101 <1/ <1

Detention/habitat ponds Drainage stations Conveyance channels Wastewater System 489 34/ 28

Wastewater Plant

Davis Wetlands

Sewerline Root Control 10/NA

Facilities 40 1/ 2 Old landfill/ pistol range Corp yards, facility parking and landscaped areas

1736 100

2008 Integrated Pest Management Report 102008 Integrated Pest Management Report 11 

## 7.0 Program Goals and Challenges for 2009

7.1 IPM Goals for 2009

PW and P&GS will continue to investigate and ut ilize feasible alternativ e pest control methods as directed by the IPM Specialist. PW will conti nue to implement its herbicide reduction plan to further refine pest control activities fo r less reliance on conventional pesticides.

The following parks will be included in the PHAER zones program:

• Winter of 2009: Central Park and Mace Ranch Park

• Spring of 2009: Arroyo Park, Walnut Park and Community Park.

• Summer 2009: Pioneer Park, Slide Hill Park, Chest nut Park, Sandy Motley Park.

• Fall 2009: Westwood Park, Barovetto Park, North Star Park and Sycamore Park.

The IPM Coordinator will continue to work on outreach such as an “Adopt-a-Park” program that recruits volunteers to participate in alternative weed control at select parks in Davis.

Public outreach and education on IPM will continue through literature and staff presentations at various public events.

Trainings will continue for P&GS and PW sta ff on pesticide safety and IPM practices.

Crew supervisors from PW will continue to test alternatives to current sewer line root control

methods. Tests on alternative herbicides and met hods will continue in order to find a less toxic

alternative.

7.2 Anticipated Challenges for 2009

Pest control strategies are dict ated by weather, pest persiste nce and staff availability to implement management techniques. Persistence of infestations and budgetary constraints may

hinder alternative cont rol methods and cause an increased reliance on conventional methods primarily because the service level standards exp ected by the community. While the majority of staff has accepted and works with IPM practices, some concern over effec tiveness of alternative methods continues. Primarily, the concern is that alternative methods are not cost effective and may not be suitable in certain applications. The IPM specialist will continue to work with staff and management to keep them informed on pe sticide regulation updates, safety, and conduct field trial to demonstrate alternatives, their effectiveness, limitations and costs.