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Top crops for cheimcals

When you’re doing your grocery shopping next time, here’s a report you might want to consider.  The Environmental Working Group (EWG) has recently published its seventh annual “Shopper’s Guide to Pesticides in Produce” which presents a list of the produce that has the most and least pesticide residue on it.  This does not mean that the produce on the list had the most or least pesticides applied, but rather tests the amount still on it by the time you are ready to eat it.  The point of the guide is to allow you to pick which fruits and vegetables you may want to consume in place of others while still getting your daily minimum fruits and vegetables for a healthy diet, NOT to discourage you from eating fruits and vegetables entirely!  It is important to note that all the produce, even the “worst” fruit of the list, still falls well below the safe levels set by the EPA, so all of the produce on the list had safe levels.

Here’s the report’s fndings, as published on walletpop.com:

 

The highest levels of pesticide residue -- and dubbed EWG's "Dirty Dozen" are:

1.Apples

2.Celery

3.Strawberries

4.Peaches

5.Spinach

6.Imported nectarines

7.Imported grapes

8.Sweet bell peppers

9.Potatoes

10.Blueberries

11.Lettuce

12.Kale/collard greens

 

The produce with lowest levels of pesticide residue as determined by the EWG, starting with what ranked the lowest, are:

1.Onions

2.Sweet Corn

3.Pineapples

4.Avocados

5.Asparagus

 

Debuting on the list this year is cilantro, which had not been previously tested by the USDA. The data showed 33 unapproved pesticides on 44% of the cilantro samples, which the EWG said was the highest percentage recorded on any items included in the guide since the data tracking started in 1995. Green onions (ranked No. 29), cranberries (No. 36) and mushrooms (No. 39) were also newcomers to the list.

 
 

Governments fail to protect invertebrates

As climates change due to human and natural factors, we rarely give thought to the insects, arachnids and other invertebrates that are both necessary to human agricultural industry, and to the stability of the ecology.

According to Endangered Invertebrates: the case for greater attention to invertebrate conservation by Scott Black, Matthew Shepard, and Melody Allen of the Xerces Society (www.xerces.org),  the US Endangered Species Act and international endangered species laws do little to protect the invertebrates.

They report that currently, only 37% of U.S. animal species listed as endangered are invertebrates and only 1% of listed foreign endangered species are invertebrates. 

This is particularly troubling considering, as the Xerces Society did, that a 20% extinction of total global diversity is possible by 2022 if the present rate of environmental destruction continues—and that this pressure is concentrated among the invertebrates: freshwater bivalves, for instance, are among the most endangered groups of organisms in North America.

 

Great Urgency to Protect Invertebrates

 

In the United States, freshwater mollusk fauna, especially rich in mussels and gillbreathing snails, is the largest in the world and the most well studied.  The species have been steeply declining in numbers from the damming of rivers, pollution, and introduction of alien mollusks and other aquatic animals.  In 1995, it was observed that just under half of all the freshwater mussels were imperiled.

But it is not just mussels.  Many insect species are vulnerable because their populations have a severely restricted distribution, often just a single locality. “The giant flightless darkling beetle (Polposipus herculeanus), for instance, lives only on dead trees on the tiny Frigate Island in the Seychelles. The Socorro sowbug (Thermosphaeroma thermophilum), an aquatic crustacean that has lost its natural habitat, survives in an abandoned bathhouse in New Mexico,” explains Xerces. 

Although freshwater and land mollusks are sometimes widespread species, they are generally vulnerable to extinction because so many are specialized for life in specific habitat conditions and are unable to move quickly from one place to another.

As a result, isolated populations are highly susceptible to change. “Rare insect species often have subtle habitat requirements and have even been lost from reserves as a result of apparently minor habitat changes,” explains Xerces.  “The large blue butterfly (Maculina arion) larvae is an obligate parasite of red ant (Myrimica sabuleti) colonies. Accordingly, in 1979 this butterfly went extinct in England because plant communities were not managed for the ants. (The large blue has subsequently been successfully reintroduced to appropriately managed sites in England using a subspecies from Sweden.)”

 

Invertebrates Require Specialized Microecosystems

 

Studies of some European grasslands have shown that areas not grazed or reforested harbored significantly higher butterfly species richness and heterogeneity, and hosted more endangered species than grasslands in the early successional stages (Balmer and Erhardt 2000). Oldgrowth forests in temperate zones also have higher invertebrate diversity than younger stands because of the development of the microclimates that invertebrates thrive in.

Yet tropical rain forests however hold the majority of terrestrial invertebrate diversity and with rainforests and temperate old growth forests around the world being lost at a rapid rate, invertebrates are bound to go with them.

 

While Larger Governments Fail, Local Governments, Citizens and Homeowners Can—and Must—Act NOW

 

“The widespread destruction of the earth's biodiversity occurring today must be matched by a conservation response on an order of magnitude greater than that which currently exists. Ultimately, the key to protection of any species is protecting its habitat,” explains Xerces.

But with little leadership found in governmental agencies, community–level conservation will be required. 

And this may be best developed through the development of amateurs who enjoy watching—and watching out after—invertebrates.

It should be hoped that these amateur enthusiasts would advocate in their local governments for the designation of wilderness areas, conserved for the benefit of many species, or for the protection of invertebrates in particular. 

Since many invertebrates only need small areas to thrive, this  goal is easily obtainable by even the smallest local government…

Or the homeowner.

Backyard gardens can function as adequate reserves for many invertebrates and encouraging homeowners—and the cities who would otherwise require them to destroy the weeds and ecology the invertebrates require—to undertake the necessary private action to save invertebrates is urgent.

Yet habitat must also be protected for marine species and marine reserves will require larger governmental action.

The power of citizens to petition their governments will be important at this juncture in our planet’s history as we embark upon a trying period of extinction when many wonderful creatures will be lost forever.

 

Assistance in Writing Petitions

 

The Meadowlark Herald will provide free assistance to any citizen interested in conserving invertebrates in their Town, City, County or State through the conservation of wilderness, the illegalization of the environmental toxins that threaten invertebrates, through the legalization of homeowner conservation efforts, or other effective means.

Petitions are easy, usually free of cost, and highly effective ways for an individual who is concerned about the interests of their neighborhood to make necessary and good laws.

Politicians do not have a monopoly on lawmaking any more than professional biologists can monopolize the joy and important observation of wild creatures.  

And it is the obligation of those interested amateurs who enjoy the invertebrates—and all the other living creatures of this world—to stand up and speak upon their behalf, and defend those beautiful and important ecology they love.

 
 

Biodiversity better than pesticide

Doctors Dr. W. Wyatt Hoback and Dr. Kerri M. Skinner of the University of Nebraska at Kearney and Dr. Robert K.D. Peterson and Dr. Sharlene E. Sing of Montana State University have combined their efforts to form RELEASE (Risk Evaluation Learning to Explore Alien Species Establishment) to help improve the understanding of the decision-making process that precedes the release of biological control agents.

Besides providing online lessons in identification, ecology, entomology and other sciences (at http://cgi.unk.edu/hoback/home.html), the Doctors provide information on successful alien species establishment.

On our farm, we rely on biodiversity to achieve a natural balance of predators and prey, and rarely suffer any crop damage because of our dedication to providing both habitat and food for the wild creatures who would not naturally want to eat our food!

 

The Successful Control of Saltcedar by Asian Leaf Beetles

 

In example, they point to the Asian Leaf Beetle to target Saltcedar (Tamarix spp.), a non-native, invasive tree that has been problematic in most southwestern states and some north-central states.

Saltcedar has infested about 1.5 million acres, increasing its range by a rate of about 50,000 acres per year.  It prefers riparian areas, especially waterways with receding surface water, and results in $127-$291 million in damages annually.

“The risk assessment for this non-native biocontrol agent release has been one of the most extensive and complete analyses to date. Research and testing of host-range parameters were conducted from 1992 to 1996 in Europe and Asia at cooperating facilities, along with select species tested in quarantine facilities at Temple, Texas,” encourage the Doctors.

Before making their recommendation, they test the alien species for host specificity and non-target effects (on phylogenetically related species, species in close proximity of infested areas, species with similar habitat requirements, and species of agricultural or horticultural concern).  Their tests utilize several experimental designs, including no-choice, choice and multiple choice for larva and adults. The survival of beetles and the extent of damage was measured.

In their tests, they found that the saltcedar was fed upon by both adult and larval stages, which enjoyed foliage, twigs and first-year shoots especially.  This caused the gradual dieback of stems, death of small plants and limited regrowth.

Expected results of beetle release are decreased saltcedar stand density, reduced saltcedar size (foliage cover), increased wildlife activity, decreased soil salinity, and restored groundwater.

And, proving their research, a northern Nevada release site has had considerable success with the biocontrol beetle release. In 2002, there were 5 acres noticeably affected by beetle defoliation, and in 2003 this increased to 500 acres. By 2004, the beetles damaged saltcedar trees in the surrounding 50,000 acres.

And, best of all, since the open field releases in 2001, there have not been any identified non-target effects of this biocontrol agent.

Similar success has been had with the decapitating fly controlling the fire ant, and the thistlehead weevil controlling the musk thistle.

 

How They Recommend Undertaking Risk Assessment

 

The scientists draw an example surrounding a salt shaker in a classroom.  11 Tablespoons would be fatal to a person weighing 150 pounds.  This threat is real, but risk assessment is required before taking action to prevent death.

First it is important to understand both the effects of exposure and the methods of exposure.

Analysis of how the salt could kill someone (exposure through ingestion, skin contact, inhalation, etc.) yields understandings of how to prevent that catastrophe, and might also illuminate the hazard of the shaker itself (which, if applied incorrectly to the body, could also be lethal). 

When these potential exposures are understood, probabilities of their occurrence can be calculated based on experimental or natural data. 

The Doctors fall short of requiring an examination of  requiring a financial analysis to determine whether it makes sense to prevent death by salt (or shaker), understanding that when lives are on the line, money is of little consequence.

In our opinion, this demonstrates uncommon ethical and moral fiber, and a loyal public service.  The cost of a person’s life (or the life of any other living  creature) cannot be quantified by money, even if their value as a resource to industry can be.

 

Interpretation

 

While it is impressive that these aliens have successfully controlled their target, it is more so that they have not complicated the ecology further by affecting other creatures.

A zero-tolerance for risk, while impracticable, is sometimes necessary when the lives of humans and other living plants, animals and microorganisms are involved.  Life is precious in all its forms, and it is better to do no harm  than to undertake something that will knowingly further destroy the delicate balance of an ecology.

While aliens are not uncommon, and species naturally migrate and disperse throughout the planet, the rapidity at which strange new creatures are being accidently and widely introduced has caused mayhem to the local environments that receive them. 

Change is best when it happens slowly, and the noble efforts of the RELEASE Group to help speed the stabilization of the biosphere are better than could be expected. 

By providing to industry another tool to rely upon in the control of pests besides chemicals, the RELEASE Group has performed a service to posterity.  The risks of further ecological collapse due to alien introduction are small when compared against the toxicity of many of the too-commonly used chemical control agents.

Besides, the cost of alien introduction is so small (and is, on top, a nearly one-time expense) that the savings to private and public purses is enormous.

 

In Motion Picture

 

An interesting video on the project is available online from the USDA at http://www.snarc.ars.usda.gov/is/video/vnr/saltcedar.htm

 

 
 
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