About GarryRogers

Dr. Garry Rogers is a biogeographer with interests in natural landscapes, vegetation ecology, and nature conservation. He agrees with the logic of the ecocentric view that all of nature, the atmosphere, biosphere, geosphere, and hydrosphere, has intrinsic value.

Some Weed Problems

Some Weed Problems Introduction

Giant Hogweed (Heracleum mantegazzianum) by Walter J. Pilsak

We know and love (or, more commonly, hate) weeds for their ability to spread to and cover bare soil exposed by fires, floods, plows, and garden spades. Like band-aids on skinned knees, weeds protect soil from erosion by wind and water. This is good, and should be good enough for us to be selective (not stereotyping) in our attitude toward weeds. But it isn’t. The reason for our persistent hatred is that weeds can compete with and replace crop and garden plants, they can replace native vegetation, and they can block vision and even travel. And, as you will see in the first article below, some weeds have toxic chemicals for defense and aggression and can inflict serious injury to grazers or innocent passersby.

Giant Hogweed (by Appaloosa)

People used to use the techniques of organic gardening to prevent and eradicate weeds. However, in the middle of the last century, science gave us herbicides, chemicals that interfere with weed growth and reproduction. What a pleasure to wave our spray wand over weeds and watch them shrivel and die. For decades, agricultural scientists have improved herbicides. They have even paired them with genetically modified crop plants that aren’t hurt by the magic spray that kills invading weeds.

Herbicides disrupt nature and cause cancer in humans. The chemical industry claims that reduced cost of food production justifies herbicide use. However, herbicides are growing stronger and farmers are applying them more heavily. This increases the harm to nature and human health.

Weeds are not defenseless against herbicides. Most of them produce seeds for the next generation in a single year, and this allows natural selection of herbicide-resistant plants within a few years. As described in the second article below, weed resistance is exceeding the power of the herbicides. As the gap between herbicide efficacy and weed resistance grows, farmers will return to the old organic gardening techniques. Though this will be less harmful to nature and people, it will increase the cost of farmed produce. Consequently, we may have to reduce meat production, a major consumer of farm crops, and, eventually, we will have to reduce human population size.

The articles below include recent discussions of weed problems.

Some Weed Problems References

Click for more on weeds.

Conservation Easement for Coldwater Farm

Introduction–Coldwater Farm

Coldwater Farm includes a small riparian forest in the river floodplain.

In 1997, my wife and I purchased a small farm beside the Agua Fria River. The farm includes a section of the river, three large ponds, and many trees, shrubs, grasses, and weeds. Since the property crosses the Agua Fria River, we decided to name the place Coldwater Farm.

Coldwater Farm is in a rural area where we get frequent glimpses of wildlife that urban dwellers never see. In early evenings when the moon is full, we often see raccoons, skunks, javelina, rabbits, and foxes foraging for the sunflower seeds we scatter for the birds. Under the last full moon, the Pink Moon of spring, a young skunk and a young raccoon searched for seeds side by side, the tips of their fur occasionally brushing seemingly unnoticed. In the spring and through the summer and fall, deer spend their days and sometimes their nights at one of our ponds and in our yard. They and the other animals we see brighten our lives. And they evoke our sympathy.

Permanent Protection with a Conservation Easement

The Central Arizona Land Trust (CALT) has accepted responsibility for establishing and monitoring a Conservation Easement for Coldwater Farm. The easement will protect wildlife habitat by preventing future development. Though we can’t add any buildings or damage the wildlife habitat, we can continue to live on the farm and we can leave it to our children. Neither our children nor any future owners of the farm can build on the land or damage the habitat. CALT has launched a fundraising campaign to cover the costs of surveys, appraisals, and a permanent trust fund to pay for annual monitoring.

After we moved to the farm, we began listing wildlife species that we saw. Our bird list has 129 species and includes the Yellow-billed Cuckoo and the Southwest Willow Flycatcher, both on the U. S. Endangered Species list. We have summarized our observations on the farm and its surroundings in four books:

If you’ve been watching the news, you know Earth is in the early stages of the Sixth Mass Extinction of wild plants and animals. Some scientists warn that the continued loss of species coupled with global warming, droughts, and large wildfires will remove much of the vegetation that protects the soil from wind and water erosion. Soil is our most fundamental biological resource. It anchors and feeds the roots of plants, and it absorbs and stores rain and snow melt. Without soil, even small rains cause floods. Without soil, Earth would be as barren as the Moon.

We know that our house, sheds, and pastures replaced habitat that wild animals could use. As we have learned the importance of wild plants and animals for healthy ecosystems, we have realized that the land was not ours to use without regard for the consequences for wildlife. Though we cannot replace the lost habitat, we can protect what remains.

The World Wildlife Fund (WWF) reports that since 1970, the average size of all plant and animal populations on Earth has fallen by over 50%. WWF predicts that by 2100, the decline will reach 90%. As populations fall, soil becomes more vulnerable and extinctions climb. All those beautiful, innocent creatures that are ours to see by the wonder of millions of years of genetic trial and error, gone forever. Edward O. Wilson and other naturalists believe to stop the losses we must set aside one-half of Earth’s land and seas exclusively for wildlife. Could we do that?

We could, but we need a united global effort.

One of the ponds at Coldwater Farm

Conservation easements are important in the global effort to preserve wildlife. Twenty-seven percent of the United States is already federal protected land—forests, multiple-use lands, parks, monuments, and wilderness. If we make small landuse adjustments to restrict livestock grazing and recreation, we will be half way to the level of conservation needed for wildlife populations to halt their decline and begin to increase. Simple arithmetic shows that if the people of the United States and other countries redirected their taxes to conservation, we could buy back the land needed to reach 50% within a few years. If, during the same period, we incentivized renewable energy and phased out fossil fuels, we could assure that wildlife would survive as human civilization continued to advance. My wife and I want to do our part. Though tiny compared to the global need, our conservation easement is a symbol. It is a step in the right direction. We hope that many other landowners will be inspired to use conservation easements to help protect their land.

Livestock and Humans Have Replaced Most Wild Animals

GR: In this study, the investigators analyzed global biomass, a common measure of animal and plant abundance, to estimate changes in the abundance of organisms. They found that humans and livestock account for 96% of all vertebrates on Earth. Previous global estimates have used numbers, not biomass, to estimate abundance. The results agree, but the new study was able to extend estimates farther back in history. Both approaches conclude that more than half of all animals have been lost since 1970. The investigators in the new study found that since human civilisation arose, 83% of wild mammals have disappeared.

The Guardian added excellent graphics to illustrate the research findings.  Highly recommended!

A cattle feedlot in Mato Grosso, Brazil. 60% of all mammals on Earth are livestock. Photograph: Daniel Beltra, Greenpeace

“Humankind is revealed as simultaneously insignificant and utterly dominant in the grand scheme of life on Earth by a groundbreaking new assessment of all life on the planet.

“The world’s 7.6 billion people represent just 0.01% of all living things, according to the study. Yet since the dawn of civilisation, humanity has caused the loss of 83% of all wild mammals and half of plants, while livestock kept by humans abounds.

“The new work is the first comprehensive estimate of the weight of every class of living creature and overturns some long-held assumptions. Bacteria are indeed a major life form – 13% of everything – but plants overshadow everything, representing 82% of all living matter. All other creatures, from insects to fungi, to fish and animals, make up just 5% of the world’s biomass.

“Another surprise is that the teeming life revealed in the oceans by the recent BBC television series Blue Planet II turns out to represent just 1% of all biomass. The vast majority of life is land-based and a large chunk – an eighth – is bacteria buried deep below the surface.

“I was shocked to find there wasn’t already a comprehensive, holistic estimate of all the different components of biomass,” said Prof Ron Milo, at the Weizmann Institute of Science in Israel, who led the work, published in the Proceedings of the National Academy of Sciences.

“I would hope this gives people a perspective on the very dominant role that humanity now plays on Earth,” he said, adding that he now chooses to eat less meat due to the huge environmental impact of livestock” –Damian Carrington, The Guardian.

 

Toxic Pesticide Use in National Wildlife Refuges

GR: Most of us take for granted that national land management agencies work to protect wildlife refuges and other public lands. However, at every turn, for instance livestock grazing in wilderness areas, we find that destructive commercial enterprises are using the land. In a new report, the Center for Biological Diversity reveals pesticides are being used in national wildlife refuges.

“WASHINGTON— America’s national wildlife refuges are being doused with hundreds of thousands of pounds of dangerous agricultural pesticides every year, according to a first-of-its-kind analysis by the Center for Biological Diversity.

“The Center report, No Refuge, reveals that an estimated 490,000 pounds of pesticides were dumped on commodity crops like corn, soybeans and sorghum grown in national wildlife refuges in 2016, the most recent year for which data are available. The analysis was conducted with records obtained by the Center under the Freedom of Information Act.

“These refuges are supposed to be a safe haven for wildlife, but they’re becoming a dumping ground for poisonous pesticides,” said Hannah Connor, a senior attorney at the Center who authored the analysis. “Americans assume these public lands are protected and I think most people would be appalled that so many pesticides are being used to serve private, intensive agricultural operations.”

“The pesticides include the highly toxic herbicides dicamba and 2,4-D, which threaten the endangered species and migrating birds that wildlife refuges were created to protect. Refuge pesticide use in 2016 was consistent with pesticide applications on refuges over the previous two years, the Center analysis showed.

“America’s 562 national wildlife refuges include forests, wetlands and waterways vital to thousands of species, including more than 280 protected under the Endangered Species Act.

“Yet intensive commercial farming has become increasingly common on refuge lands, triggering escalating use of highly toxic pesticides that threaten the long-term health of these sensitive habitats and the wildlife that depend on them.

“In 2016 more than 270,000 acres of refuge land were sprayed with pesticides for agricultural purposes. The five national wildlife refuge complexes most reliant on pesticides for agricultural purposes in 2016 were:

  • Klamath Basin National Wildlife Refuge Complex in California and Oregon, with 236,966 pounds of pesticides;
  • Central Arkansas Refuges Complex in Arkansas, with 48,725 pounds of pesticides;
  • West Tennessee Refuge Complex in Tennessee, with 22,044 pounds of pesticides;
  • Tennessee National Wildlife Refuge Complex in Tennessee, with 16,615 pounds of pesticides;
  • Chesapeake Marshlands National Wildlife Refuge Complex on the Eastern Shore of Maryland and Virginia, with 16,442 pounds of pesticides.

Additional findings from the report:

  • Aerial pesticide spraying: In 2016, 107,342 acres of refuge lands were aerially sprayed with 127,020 pounds of pesticides for agricultural purposes, including approximately 1,328 pounds of the notoriously drift-prone dicamba, which is extremely toxic to fish, amphibians and crustaceans.
  • Glyphosate: In 2016 more than 55,000 agricultural acres in the refuge system were treated with 116,200 pounds of products containing glyphosate, the pesticide that has caused widespread decreases in milkweed plants, helping to trigger an 80 percent decline of the monarch butterfly over the past two decades.
  • 2,4-D: In 2016 more than 12,000 refuge acres were treated with 15,819 pounds of pesticide products containing 2,4-D, known to be toxic to mammals, birds, amphibians, crustaceans, reptiles and fish and is likely to jeopardize the continued existence of endangered and threatened salmonids.
  • Paraquat dichloride: In 2016 more than 3,000 acres of corn and soybean crops on refuge lands were treated, mainly through aerial spraying, with approximately 6,800 pounds of pesticides containing paraquat dichloride, known to be toxic to crustaceans, mammals, fish, amphibians and mollusks and so lethal it is banned in 32 counties, including the European Union.

“These pesticides are profoundly dangerous for plants and animals and have no place being used on such a staggering scale in our wildlife refuges,” Connor said. “The Interior Department needs to put an end to this outrage and return to its mission of protecting imperiled wildlife, not row crops.”

Source: Hannah Connor, (202) 681-1676, hconnor@biologicaldiversity.orgAnalysis: 490,000 Pounds of Toxic Pesticides Sprayed on National Wildlife Refuges