November 2015 – Conservation Sense and Nonsense

Public opposition to pesticide use in our public parks

On November 19, 2015, a visitor to Mount Davidson park in San Francisco video recorded a pesticide application that is available here:

One of the people who saw that video reported several concerns regarding that pesticide application to the city employees who are responsible for the regulation of pesticide use in San Francisco. Here is the email he sent to Kevin Woolen in the Recreation and Park Department and Chris Geiger in the Department of the Environment:

To: Kevin Woolen kevin.woolen@sfgov.org

Dear Mr. Woolen,

I understand that you are responsible for the records of pesticide applications on properties managed by San Francisco’s Recreation and Park Department. I have heard you speak at public meetings, so I am aware that you have some expertise in that area. Therefore, I am writing to you about a pesticide application on Mt. Davidson on November 19, 2015. That pesticide application was recorded by this video: https://www.facebook.com/ForestAlliance/videos/934479473312166/?fref=nf

I have several concerns about this pesticide application:

One of the herbicides that was sprayed was Stalker with the active ingredient imazapyr. I notice that most of the spraying was done around a tree, which was not a target of the application according to the posted Pesticide Application Notice. As you may know, imazapyr is not supposed to be sprayed under and around non-target trees according to the manufacturer’s label: http://www.cdms.net/ldat/ld01R013.pdf: “Injury or loss of desirable trees or other plants may result if Stalker is applied on or near desirable trees or other plants, on areas where their roots extend, or in locations where the treated soil may be washed or moved into contact with their roots”

Here is a newspaper article about unintentional damage done to trees by spraying an imazapyr herbicide beneath them: http://www.mlive.com/news/grand-rapids/index.ssf/2012/09/no_quick_fix_for_herbicide_dam.html

The Pesticide Application Notice says that the application method will be “spot treatment/daub cut stem.” This does not seem to be an accurate description of the application method on November 19th. It seems that “backpack sprayer” would be a more accurate description of this particular pesticide application.

The Pesticide Application Notice says that Himalayan blackberries were one of the targets of this Pesticide Application. As you know, birds and other wildlife cannot read the signs that are posted to warn the public about these applications. Can you assure me that the Himalayan blackberries were no longer fruiting? Does the Recreation and Park Department have a policy against spraying vegetation when there are fruits eaten by birds and other wildlife? If not, would the Recreation and Park Department consider adopting such a policy?

Although Garlon was not used in this particular pesticide application, it is often used in San Francisco’s so-called “natural areas.” Therefore, it is worth mentioning that Garlon is also known to be mobile in the soil and there are documented incidents of it damaging non-target trees when it has been sprayed on the stumps of nearby trees after they were destroyed.

Thank you for your consideration. I hope you will share my concerns with the staff and contractors who are engaged in these pesticide applications.

Cc: Chris Geiger chris.geiger@sfgov.org

This is not an isolated incident. Park visitors in San Francisco have been complaining for years about pesticide use in parks that were designated as “natural areas” over 15 years ago. Ironically, those areas were never sprayed with pesticides before being designated as “natural areas.” In fact, they really were natural areas prior to being officially designated as such. Plants and animals lived in peace in those places before being “managed” by people who are committed to eradicating all non-native plants in many of San Francisco’s parks.

What can you do about it?

If you are opposed to pesticide use in San Francisco, or you object to the pointless destruction of harmless plants that are useful to wildlife, here are a few things you can do to express your opinion and influence the public policy that allows pesticide use in the public parks of San Francisco:

You can join over 11,000 people who have signed a petition to prohibit the use of pesticides in public parks. The petition is HERE. The San Francisco Chronicle reported on pesticide use in San Francisco’s parks and the petition against that use. (Available HERE)
You can sign up HERE to be notified of the annual meeting in which pesticide policy in San Francisco is discussed for subsequent approval by the Environment Commission. That meeting has been scheduled in December in past years. Update: The annual meeting has been announced. “Annual Public Hearing on Pest Management Activities on City Properties and San Francisco’s Draft 2016 Reduced-Risk Pesticide List 4:30-7:00 pm
Wednesday, December 16, 2015 Downstairs Conference Room, 1455 Market St. (near 11th St.; Van Ness MUNI stop)” The meeting agenda is available HERE.
You can apply for one of the two vacant seats on the Environment Commission. These seats have been vacant for nearly a year. In the past, the Environment Commission has actively promoted pesticide use in San Francisco’s “natural areas.” Qualifications and duties of commissioners are available HERE.
Appointments to the Environment Commission are made by Mayor Ed Lee. If you don’t want to serve on the Environment Commission, you can write to Mayor Lee (mayoredwinlee@sfgov.org) and ask him to appoint people to the Commission who do not support the use of pesticides in San Francisco’s public parks.

The parks of San Francisco belong to the people of San Francisco. They have paid to acquire those properties for public use and they are paying the salaries of those who are “managing” the parks. If you don’t like how parks are being managed, you have the right to express your opinion. Our democracy works best when we participate in the public policy decisions that affect us.

What does this have to do with the East Bay?

Our readers in the East Bay might wonder what this incident has to do with you. Parks in the East Bay are also being sprayed with herbicides for the same reasons. HERE are reports of pesticide use by the East Bay Regional Park District.

Many of the pesticide applications on the properties of EBRPD are done by the same company that sprayed herbicides on Mount Davidson on November 19, 2015. That company is Shelterbelt Builders. You can see their trucks in the above video. Pesticide use reports of San Francisco’s Recreation and Park Department often report that pesticide applications were done by Shelterbelt.

Shelterbelt began the eradication of non-natve vegetation in Glen Canyon in November 2011

Shelterbelt Builders is based in the East Bay. One of its owners is Bill McClung who is a member of the Claremont Canyon Conservancy and a former officer of that organization. The Claremont Canyon Conservancy is the organization that is demanding the eradication of all non-native trees on public land in the East Bay Hills. Here is a description of Mr. McClung’s responsibilities on Shelterbelt’s website:

“Bill McClung joined Shelterbelt in 1997 to help refocus Shelterbelt on native plant restoration and open land management/fire safety. After his house burnt down in the 1991 Oakland Fire, this former book publisher became interested in how wildland and fire are managed in the East Bay Hills. He became a member of the Berkeley Fire Commission in 1994 and has a strong interest in the vegetation prescriptions of the Fire Hazard Program & Fuel Reduction Management Plan for the East Bay Hills issued in 1995 by the East Bay Hills Vegetation Management Consortium and the East Bay Regional Park District Wildfire Hazard Reduction and Resource Management Plan Environmental Impact Report of 2009/10. He has managed many properties in the East Bay where wildfire safety and native habitat preservation are twin goals, and continues to work on interesting and biologically rich lands in the Oakland Hills.”

Claremont Canyon Conservancy

The Claremont Canyon Conservancy held their annual meeting on November 15, 2015. Oakland’s Mayor, Libby Schaaf, was one of the speakers. Although she took questions at the end of her presentation, one of the officers of the Conservancy called on the questioners. There were many people in the audience who are opposed to the FEMA projects that will destroy over 400,000 trees in the East Bay Hills and many of us tried to ask questions. With one exception, the person controlling the questions only called on known, strong supporters of the FEMA project. Therefore, those who wished to express their opposition to the FEMA projects to the Mayor were denied that opportunity. Fortunately, there were many demonstrators outside the meeting who could not be denied that opportunity.

Norman LaForce was the other main speaker at the meeting. He is an elected officer of the Sierra Club and he identified himself as one of the primary authors of the project to destroy all non-native trees in the East Bay Hills. (An audio recording of his complete presentation is available here: https://milliontrees.me/wp-content/uploads/2015/11/norman-laforce-sierra-club-11-15-15.m4a ) This is the paraphrased portion of his presentation specifically about the herbicides that will be used by the FEMA project:

“Part of the FEMA program will be to use herbicides in a concentrated, careful program of painting or spraying herbicides to prevent the trees from resprouting. It may need to be done more than once but ultimately the suckers give up. There is no other way to do that cost effectively.

People are saying that glyphosate causes cancer. Radiation causes cancer but when people get cancer they are often treated with radiation. Nobody tells them they can’t have radiation because it causes cancer.

There are a lot of people of a certain age in this room who are probably taking Coumadin as a blood thinner for a heart condition. Coumadin is rat poison. Nobody tells them they can’t take Coumadin.*

You must take dosage and exposure into consideration in evaluating the risks of pesticides.

Nature Conservancy used glyphosate on the Jepson Prairie.

State Parks used Garlon on Angel Island when they removed eucalyptus.

The European Union says that glyphosate does not cause cancer, so I don’t know if it does. I’m not going to take a position on that.

Now they are saying that red meat causes cancer.

We need to put aside the question of pesticides. They will be used properly. We must proceed in a scientific manner.”

We leave it to our readers to interpret Mr. LaForce’s justification for pesticide use. He seems to be suggesting that pesticides are good for our health. There are instances in which pesticides do more good than harm, but using them to kill harmless plants in public parks isn’t one of them, in our opinion. Since many chemicals accumulate in our bodies throughout our lives, it is in our interests to avoid exposure when we can. If we must take Coumadin for our health, that’s all the more reason why we should avoid unnecessary exposure to rat poison when we can.

Connecting the dots

We have tried to connect the dots for our readers. Here are the implications of what we are reporting today:

Pesticide applications in San Francisco are probably damaging the trees that are not the target of those applications. The food of wildlife may be poisoned by those pesticide applications.
You can influence the public policy that is permitting pesticide use in San Francisco.
The same company that is spraying pesticides in San Francisco is also doing so in the East Bay.
That company is also actively engaged in the attempt to transform the landscape in the San Francisco Bay Area to native plants. They have an economic interest in native plant “restorations.”
The Sierra Club is actively promoting the use of pesticides on our public lands.

*Coumadin is prescribed for people who are at risk of heart attack or stroke caused by blood clots. Coumadin thins the blood and suppresses blood coagulation. Rat poison kills animals by bleeding them to death. There is a fine line between preventing blood clots and bleeding to death. Therefore, people who take Coumadin have frequent blood tests to check that the dosage is at the optimal level. Rat poisons are killing many animals that are not the target of the poison. Animals such as owls, hawks, vultures are often killed by eating dead rodents that have been poisoned. We should not conclude that rat poison is harmless because humans are using it in carefully controlled doses. Herbicides being sprayed in our public lands are not being closely monitored as Coumadin use is.

Monarch myths revisited

Debunking the myths of nativism—especially those that justify the eradication of non-native trees—is the task we have assigned ourselves, which requires us to revisit a few of the misconceptions about monarch butterflies in California.

When application for endangered status for monarchs was filed in August 2014, a few new monarch myths emerged and have since been faithfully repeated by native plant advocates who are demanding the eradication of our urban forests. The monarch migration in California is using predominantly non-native trees, which should afford those trees some protection. Unfortunately, it has only produced more convoluted theories that deny the value of non-native plants and trees to monarchs.

Myth #1: The California migration of monarch butterflies prefers native trees for their winter roost.

Monarch butterflies roosting in eucalyptus tree.

A study of the trees used by monarch butterflies for their winter roost in over 300 different sites in California reported that the vast majority of monarchs are using eucalyptus:

“Three types of trees were used most frequently by roosting monarchs: eucalyptus (75% of the habitats primarily Eucalyptus globulus), pine (20% of the habitats; primarily Pinus radiata), and cypress (16% of the Cupressus macrocarpa). Twelve other tree species were identified…with a combined prevalence of only 10%.” (Three different studies by different authors are the source of these data, therefore they don’t add up to 100%.) (1)

Unfortunately, this fact has been obscured by a small study of a few selected sites used by monarchs during their migration. Griffiths and Villanova (2) observed the monarch migration in a few sites in Monterey and San Luis Obispo counties. They report that the monarchs moved around among three tree species including eucalyptus, suggesting to them that Monterey pine and cypress are equally important to the monarchs. While we don’t doubt that this may be true, we don’t think we can generalize from this study because it was conducted in the small native range of Monterey pine and cypress.

The California migration of monarchs spends the winter months roosting in tall trees in 17 counties along the coast of California, from Mendocino County in the north to San Diego County in the south. (1) Most of that expanse is outside the native range of Monterey pine and cypress. Griffiths and Villanova do not acknowledge that both Monterey pine and cypress are being eradicated outside their native range for the same reason that eucalyptus is being eradicated, i.e., they are considered “alien invaders” where they have been planted outside their native range. Here in the San Francisco Bay area, for example, 500 Monterey pines were destroyed on the Marin headlands a few years ago and an untold number of Monterey pines will be destroyed by the FEMA projects in addition to those that have already been destroyed here.

If, in fact, monarchs do have a preference for Monterey pines and cypress for their winter roost, they do not have that option outside of the small native range of those trees in Monterey County.

For the record, we should tell you that we are just as opposed to the pointless destruction of Monterey pine and cypress outside their small native range as we are opposed to the destruction of eucalyptus.

There is paleontological evidence (fossil cones) that Monterey pines lived in the San Francisco Bay Area several times in the distant past. That finding was reported (4) in Fremontia, the journal of the California Native Plant Society. The author asked that Monterey pines be allowed to remain where they lived in the past because the species is threatened in its small native range. Unfortunately, her advice has been ignored by native plant advocates, who continue to demand that all Monterey pines be destroyed where they have been planted outside their present native range. This extreme viewpoint is one of the reasons why native plant advocates have earned their reputation as fanatics.

Myth #2: The California migration of monarch butterflies used exclusively native trees before eucalyptus was planted in California.

Those who wish to discount the value of eucalyptus to overwintering monarchs often assume the California monarch migration predates the planting of eucalyptus in California in mid-19^th century. That assumption supports their claim that all of our eucalyptus can be destroyed without having a negative impact on monarch butterflies. In fact, there is no historical record of the monarch migration until the mid-19^th century. The historical record of the monarch migration was reported by Vane-Wright (3), who tells us the California monarch migration is probably a 19^th century expansion of the range of the eastern monarch migration, from east of the Rocky Mountains to Mexico. Recent molecular analysis of the monarch migration confirms that the eastern and western migration of monarchs in North America are genetically identical, suggesting that the populations might be dispersing east and west from their Mexican winter roost. (5)

Monarch caterpillar on milkweed. Tilden Botanical Garden

Monarch butterflies are not usually eaten by birds because their host plant contains a toxin that makes birds sick and the monarch’s warning colors broadcast that fact. The warning colors of butterflies that are toxic to birds are often mimicked by other species of butterflies to confer that protection. There is a monarch mimic, the Viceroy, in the eastern US, which occurs in California only in a tiny bit of riparian habitat in southeast California. “The lack of mimics suggests the [monarch] may not have been here long enough for any to evolve.” (6)

Myth #3: Non-native species of milkweed is harmful to monarch butterflies.

Monarch butterflies lay their eggs on milkweed and their larvae, the caterpillar, feeds exclusively on milkweed. Many native plant advocates believe that the monarch requires a native species of milkweed. They are mistaken in that assumption. Wikipedia lists over 35 species of milkweed (genus Asclepias) all over the world and many are known to be used by the widely dispersed populations of monarchs.

The dispersal of monarchs from their original range in North America is approximately 200 years old, according to molecular analysis of populations across the Pacific Ocean (Hawaii, Samoa, Fiji, New Caledonia, New Zealand, Australia) and across the Atlantic (Spain, Portugal, Morocco). These dispersals are assumed to have been aided by human transportation of both milkweeds and monarchs and extreme weather events. “For example, monarchs were recorded in Australia in 1870 and were most probably carried there on cyclonic winds from a source population in New Caledonia.” (7) These populations do not migrate and are therefore genetically distinct from the ancestral population of North American monarchs as a result of genetic drift.

In many of the homes of new populations of monarch butterflies there was no native species of milkweed before being introduced simultaneously with the monarch populations. Although there are numerous members of the milkweed family native to Australia, monarchs do not appear to utilize the native species, preferring the introduced species of milkweed.

Tropical milkweed (Asclepias curassavica) Creative Commons

In California, a tropical species of milkweed is popular with gardeners (Asclepias curassavica). Unlike the native species of milkweed, tropical milkweed does not die back in winter. Gardeners therefore tend to prefer the tropical milkweed because it makes a colorful contribution to their gardens year around.

Of course, native plant advocates prefer native species of milkweed and they justify their preference by claiming that tropical milkweed is harmful to monarchs. They claim that the monarch parasite (Ophryocystis elektroscirrha) can accumulate on tropical milkweed because it doesn’t die back during the winter. Tropical milkweed is the only milkweed available in winter. The parasite disrupts some winter breeding of monarchs, but that breeding would not occur in the absence of tropical milkweed. If more monarchs are the goal, tropical milkweed is making a contribution to the monarch population.

New scientific research debunks the myth that tropical milkweed is harmful to monarchs. Leiling Tao et.al. (8) studied monarch lifespans when they fed on a variety of milkweed species. They looked at both resistance to monarch parasite (O. elktroscirrha) infection and tolerance once infected. They found a complex interaction between species of milkweed the monarchs fed on and the amount of mycorrhizal fungi on the roots of the milkweed. But one result was clear: monarchs raised on tropical milkweed (A. curassavica) lived as long, or longer than, monarchs raised on other species of milkweed. They were less likely to be infected, and once infected, tolerated the infection well. In short, there is nothing about tropical milkweed as a host that is detrimental to monarch survival in the presence of parasites.

Native plant advocates also speculate that tropical milkweed can disrupt the migratory patterns of monarchs because it is available when native milkweed is not available. Given that monarchs have persisted for 200 years all over the world, using exclusively non-native milkweed and without migrating, this seems an unnecessarily pessimistic concern. Neither native milkweed species, nor migration are essential to the survival of monarchs as a species.

Peek under the cover story

As we often do on Million Trees, we have taken a peek under the cover story being used by native plant advocates to justify the eradication of non-native plants and trees. Once again, we find a lot of pessimistic speculation, but little evidence that eradicating non-native plants will benefit wildlife, or conversely that wildlife can only survive in native habitat. Yes, it was a tedious journey to that conclusion and we thank you for your patience if you have persevered to our optimistic conclusion that wildlife is far more resourceful and resilient than nativism wishes to believe.

(1) Dennis Frey and Andrew Schaffner, “Spatial and Temporal Pattern of Monarch Overwintering Abundance in Western North America,” in The Monarch Butterfly Biology and Conservation, Cornell University Press, 2004.

(2) Jessica Griffiths and Francis Villablanca, “Managing monarch butterfly overwintering groves: Making room among the eucalyptus,” California Fish and Game 101(1): 40-50; 2015. Summary also available HERE.

(3) Richard Vane-Wright, “The Columbus Hypothesis: An Explanation for the Dramatic 19^th Century Range Expansion of the Monarch Butterfly,” in Biology and Conservation of the Monarch Butterfly,Natural History Museum of Los Angeles County, 1993.

(4) Constance Millar, “Reconsidering the Conservation of Monterey Pine,” Fremontia, Vol. 26, No. 3, July 1998

(5) Justine I. Lyons, et. al., “Lack of genetic differentiation between monarch butterflies with divergent migration destinations,” Molecular Ecology, (2012) 21, 3433-3444

(6) Art Shapiro, Field Guide to Butterflies of the San Francisco Bay and Sacramento Valley Regions, California Natural History Guides, UC Press, 2007.

(7) Amanda Pierce, et. al., “Serial founder effects and genetic differentiation during worldwide range expansion of monarch butterflies,” Proceedings of the Royal Society of Britain, 281: 2014.2230.

(8) LeilingTao, et. al., “Disease ecology across soil boundaries: effects of below-ground fungi on above-ground host—parasite interactions,” Proceedings of Royal Society of Britain, 282: 2015.1993.