I'm interested in people who have traveled the world, learning from the diversity of human adaptations and health responses.
Esther Gokhale
Weston A. Price
Jaws: The Story of a Hidden Epidemic
Thursday, December 26, 2019
Logging to Save a Forest from Climate Change
A good article about logging in the forest where I did my graduate research in northern Michigan. Researchers are using funding from a timber contract with Louisiana-Pacific to cut the aspen trees on part of the experimental forest. They will study the soil and water impacts of cutting the trees, as well as looking at species composition changes.
In the article, a researcher is quoted as saying that it would be irresponsible not to cut the trees because of climate change. "Aspen in the Great Lakes region are considered “climate change losers,” according to Nave, and are not expected to fare well as the region’s climate continues to warm in the coming decades."
"The high-emissions scenario projects an 11.2-degree Fahrenheit summer temperature increase in the assessment area by the end of the 21st century. At the same time, summer precipitation is projected to decline by 3.8 inches under that scenario. "
"It will take a decade or more to know which of the aspen-management treatments was most effective, Nave said. It is expected that future generations of Biological Station researchers and students will carry on with the work, he said."
In the article, a researcher is quoted as saying that it would be irresponsible not to cut the trees because of climate change. "Aspen in the Great Lakes region are considered “climate change losers,” according to Nave, and are not expected to fare well as the region’s climate continues to warm in the coming decades."
"The high-emissions scenario projects an 11.2-degree Fahrenheit summer temperature increase in the assessment area by the end of the 21st century. At the same time, summer precipitation is projected to decline by 3.8 inches under that scenario. "
"It will take a decade or more to know which of the aspen-management treatments was most effective, Nave said. It is expected that future generations of Biological Station researchers and students will carry on with the work, he said."
Thursday, December 19, 2019
Glyphosate Fear-Mongering
Despite recent court cases, glyphosate is not recognized as a carcinogen or toxin as these terms are normally understood in environmental toxicology. Yes, there is some research linking glyphosate with increased cancer risk, but that is not the scientific consensus.
I don't think this blog post on glyphosate can be counted as scientifically accurate, even though it does cite scientific research. Websites that sell fear based on a few studies while ignoring the body of scientific literature are not reliable sources for decision-making.
I am writing as a concerned science-lover. For me (and I could be wrong), I see glyphosate fear-mongering as no different from conspiracy theories about vaccine harms or global warming. Yes, there are scientific papers showing that vaccines cause autism and that global warming is not happening, but any article that only cites those papers without weighing (or at least mentioning!) the current scientific consensus would be misleading at best.
Focusing on glyphosate seems especially misguided given the other chemicals used in agriculture and commonly found in our food supply (e.g. chlorpyrifos). While glyphosate may be the popular boogeyman of the year, science-based reporting should at least acknowledge that it is probably the least toxic of any chemical pesticides currently being used.
A better approach than just selling fear: promote solutions, such as better testing of all chemicals in our food supply.
Wednesday, December 18, 2019
Plant Interactions Versus Integrated Vegetation Management (IVM)
Questions: does existing vegetation help or hurt the
IVM goal of creating a self-sustaining, compatible plant community? Do
some compatible species tend to facilitate or inhibit the establishment and
growth of incompatible species? And do these plant interactions vary
systematically across ecosystems?
These questions fall into the domain of “Community
Ecology”. This
looks like a good review paper but I don’t have access to it. Ecology
is notoriously unsystematic, so (without reading the review) I bet the answer
is “Its complicated” and “It depends.”
Here are some papers I was able to
access:
Paper: The role of plant interactions in the restoration of
degraded ecosystems: a meta‐analysis across life‐forms and ecosystems
Relevant Conclusions: Inhibition predominates in
herbaceous communities typical of early‐successional stages, whereas
facilitation prevails in communities dominated by shrubs and trees.
My Comment: IVM that leaves shrubs (like in Sonoran desert)
would probably not create inhibition for tree growth, whereas IVM that leaves
grasses (like Ponderosa habitats) would be expected to inhibit tree growth.
Paper: Is the change of plant–plant interactions with
abiotic stress predictable? A meta‐analysis of field results in arid
environments
Relevant Conclusions: Density data showed that the net
effect of plant neighbours was positive at low abiotic stress and negative at
high abiotic stress levels. However, none of our meta‐analyses indicated
that the magnitude of the net effect provided by plant neighbours, whether
positive or negative, was higher under high abiotic stress conditions, and
facilitation does not therefore appear to increase in importance with abiotic
stress.
My Comment: Results are mixed, but in general deserts do not
show more importance of “nurse plant” facilitation.
Wednesday, August 07, 2019
Rosemont mine delayed by 1872 Mining Law
Quotes from Arizona Daily Star:
In his 37-page decision, Soto hammered almost exclusively at the Forest Service’s approval of Hudbay’s plan to dump mine waste rock and tailings from its 955-acre pit onto 2,447 acres of nearby public land on the Santa Ritas’ eastern slopes.
Opponents’ lawsuits argued that only public lands directly above valuable mineral deposits are covered by the federal 1872 mining law’s definition of mining rights.
Soto wrote in his decision that for Hudbay to gain access to valuable copper, molybdenum and silver from the pit, the company would need to extract about 1.2 billion tons of economically worthless waste rock and about 700 million tons of mine tailings.
The Forest Service's primary error in this case was to accept, without question, that Hudbay's unpatented mining claims on those 2,447 acres were valid, thereby allowing them to be used for placement of the waste rock and tailings, he wrote.
Source.
In his 37-page decision, Soto hammered almost exclusively at the Forest Service’s approval of Hudbay’s plan to dump mine waste rock and tailings from its 955-acre pit onto 2,447 acres of nearby public land on the Santa Ritas’ eastern slopes.
Opponents’ lawsuits argued that only public lands directly above valuable mineral deposits are covered by the federal 1872 mining law’s definition of mining rights.
Soto wrote in his decision that for Hudbay to gain access to valuable copper, molybdenum and silver from the pit, the company would need to extract about 1.2 billion tons of economically worthless waste rock and about 700 million tons of mine tailings.
The Forest Service's primary error in this case was to accept, without question, that Hudbay's unpatented mining claims on those 2,447 acres were valid, thereby allowing them to be used for placement of the waste rock and tailings, he wrote.
Source.
Wednesday, July 10, 2019
Bark Beetles
The Threat
Records dating back as far as 1750 indicate a consistent record of intermittent outbreaks of aggressive bark beetles in various forest types across the West. Over the past 10-15 years, however, the frequency, severity, and extent of bark beetle outbreaks have increased.
The current bark beetle outbreaks differ from previously recorded infestations because of:
Their intensity — bark beetles are killing trees in larger numbers, at a faster pace, and over longer time periods
Their extent — bark beetle outbreaks are occurring in numerous ecosystems from Alaska to northern Mexico
Their synchroneity — bark beetle outbreaks are occurring concurrently across western North America
The Characters: all beetles in the subfamily Scolytinae
Dendroctonus sp (Bark beetles) Outbreaks are usually associated with drought (Page, 1981). The beetle also responds to fire-damaged trees, but not those killed by fire.
Ips sp. (Pine engraver beetles): Species within the genus Ips, such as the piñon ips and
Arizona fivespined ips, also can kill their hosts, although typically they are not considered major disturbance agents. In recent years, however, elevated population levels of a number of Ips species have coincided with drought, resulting in large areas of mortality, particularly in piñon and ponderosa pine forests of the southwestern U.S.
The above beetles are distinguished from Ambrosia beetles as they only attack and consume live trees, whereas Ambrosia beetles can bore into heartwood even after a tree is dead and dry.
Ambrosia beetles (several species): Classed as wood borer beetles that attack weakened, dying, and
recently cut or killed trees. They can attack freshly cut lumber and lumber in decks before it is dried, and they can cause pinhole defects and dark staining in the outer wood. Galleries are formed in the sapwood or heartwood and damage the wood. Because ambrosia beetles tunnel into the wood, they are considered wood borers rather than bark beetles.
Management Considerations
When live trees are blown down, their phloem can remain suitable for bark beetle development up to a year later. Stressed pine trees emit volatile compounds (terpenes). Bark beetles have evolved to detect these compounds and use them to identify suitable host trees.
Bark beetles are also attracted to freshly cut wood. Freshly processed chips emit the same volatile compounds (terpenes) as susceptible host trees. These chips will attract bark beetles during their active periods. The bark beetles cannot utilize the chips as a food source, but the attracted bark beetles may then colonize suitable host trees adjacent to the chips piles.
Fresh dead and down material (slash) can be a refuge for bark beetles, allowing them to breed, and possibly colonize nearby healthy trees. Lop and scatter can let slash dry out, killing any beetles in the bark and preventing new beetles from feeding on it.
Wood that has been debarked is not suitable for colonization by bark beetles. Only freshly cut, logs or slabs that have not been debarked are at risk of colonization.
Dead trees that do not have bark beetles in them and that do not pose a safety hazard can be left in the forest to be used by wildlife. Dead trees do not necessarily pose more of a fire hazard than live trees.
Records dating back as far as 1750 indicate a consistent record of intermittent outbreaks of aggressive bark beetles in various forest types across the West. Over the past 10-15 years, however, the frequency, severity, and extent of bark beetle outbreaks have increased.
The current bark beetle outbreaks differ from previously recorded infestations because of:
Their intensity — bark beetles are killing trees in larger numbers, at a faster pace, and over longer time periods
Their extent — bark beetle outbreaks are occurring in numerous ecosystems from Alaska to northern Mexico
Their synchroneity — bark beetle outbreaks are occurring concurrently across western North America
The Characters: all beetles in the subfamily Scolytinae
 |
| Figure from Bentz, 2005. |
Dendroctonus sp (Bark beetles) Outbreaks are usually associated with drought (Page, 1981). The beetle also responds to fire-damaged trees, but not those killed by fire.
Ips sp. (Pine engraver beetles): Species within the genus Ips, such as the piñon ips and
Arizona fivespined ips, also can kill their hosts, although typically they are not considered major disturbance agents. In recent years, however, elevated population levels of a number of Ips species have coincided with drought, resulting in large areas of mortality, particularly in piñon and ponderosa pine forests of the southwestern U.S.
The above beetles are distinguished from Ambrosia beetles as they only attack and consume live trees, whereas Ambrosia beetles can bore into heartwood even after a tree is dead and dry.
Ambrosia beetles (several species): Classed as wood borer beetles that attack weakened, dying, and
recently cut or killed trees. They can attack freshly cut lumber and lumber in decks before it is dried, and they can cause pinhole defects and dark staining in the outer wood. Galleries are formed in the sapwood or heartwood and damage the wood. Because ambrosia beetles tunnel into the wood, they are considered wood borers rather than bark beetles.
Management Considerations
When live trees are blown down, their phloem can remain suitable for bark beetle development up to a year later. Stressed pine trees emit volatile compounds (terpenes). Bark beetles have evolved to detect these compounds and use them to identify suitable host trees.
Bark beetles are also attracted to freshly cut wood. Freshly processed chips emit the same volatile compounds (terpenes) as susceptible host trees. These chips will attract bark beetles during their active periods. The bark beetles cannot utilize the chips as a food source, but the attracted bark beetles may then colonize suitable host trees adjacent to the chips piles.
Fresh dead and down material (slash) can be a refuge for bark beetles, allowing them to breed, and possibly colonize nearby healthy trees. Lop and scatter can let slash dry out, killing any beetles in the bark and preventing new beetles from feeding on it.
Wood that has been debarked is not suitable for colonization by bark beetles. Only freshly cut, logs or slabs that have not been debarked are at risk of colonization.
Dead trees that do not have bark beetles in them and that do not pose a safety hazard can be left in the forest to be used by wildlife. Dead trees do not necessarily pose more of a fire hazard than live trees.
 |
| Figure from Bentz, 2005. |
Additional Resources
Diana L. Six, Ryan Bracewell, Bark Beetles, 2015
Monday, June 10, 2019
Friday, May 10, 2019
Pollinators Fight Allergies
In the US, people often mistakenly blame the conspicuous goldenrod flower for allergies. Since this plant is entomophilous (its pollen is dispersed by animals), its heavy, sticky pollen does not become independently airborne. Most late summer and fall pollen allergies are probably caused by ragweed, a widespread anemophilous plant.
Arizona was once regarded as a haven for people with pollen allergies, although several ragweed species grow in the desert. However, as suburbs grew and people began establishing irrigated lawns and gardens, more irritating species of ragweed gained a foothold and Arizona lost its claim of freedom from hay fever.
Anemophilous spring blooming plants such as oak, birch, hickory, pecan, and early summer grasses may also induce pollen allergies. Most cultivated plants with showy flowers are entomophilous and do not cause pollen allergies.
Larger pollen grains are more likely to be transported by pollinators, whereas smaller pollen is more likely to be wind-dispersed.
This page lists pollen size by plant family.
Source:
Wikipedia and MNN.com
Arizona was once regarded as a haven for people with pollen allergies, although several ragweed species grow in the desert. However, as suburbs grew and people began establishing irrigated lawns and gardens, more irritating species of ragweed gained a foothold and Arizona lost its claim of freedom from hay fever.
Anemophilous spring blooming plants such as oak, birch, hickory, pecan, and early summer grasses may also induce pollen allergies. Most cultivated plants with showy flowers are entomophilous and do not cause pollen allergies.
 |
| Scanning electron microscope image (500x magnification) of pollen grains from a variety of common plants: sunflower (Helianthus annuus), morning glory (Ipomoea purpurea), prairie hollyhock (Sidalcea malviflora), oriental lily (Lilium auratum), evening primrose (Oenothera fruticosa), and castor bean (Ricinus communis). |
Larger pollen grains are more likely to be transported by pollinators, whereas smaller pollen is more likely to be wind-dispersed.
This page lists pollen size by plant family.
Source:
Wikipedia and MNN.com
Friday, March 01, 2019
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