Friday, January 25, 2013

Comparing Historical Wildland Photos From the Past with the Present Reality

Plants Adapt to Drought, But Limits are Looming, study says
Credit: Mitchel McClaren


The University of Arizona's Santa Rita Experimental Range is one of the large-scale/long-term study areas that are crucial for this research. Using techniques like repeat photography, inclusion or exclusion of livestock, and vegetation surveys since the 1950s, scientists study how ecosystems react to different influences such as climate change and grazing.





Very quick here. I love these historical photo comparisons on ecology. It's truly a great way to judge the present and future of the environment by viewing how things once were in the past and how things measure up today. I have often found historical photos on subjects I've written about in the present and the amazing contrast to the way the natural world is now. Clearly there are hidden away in many old trunks in peoples homes, archives of photo gems, though folks may not be aware of their actual value other than personal hand me downs. Hopefully more and more older photographs come to light and benefit researchers. Take these example by the University of Arizona and the change in vegetation of the desert landscape.


Photo by D. Griffiths; provided by M. McClaren



Repeat photography is one of the tools range ecologists use to document how lands change. In 1902, photographer David Griffiths' horse-drawn buggy was clearly visible in the open grassland, surrounded by scattered desert hackberry plants at the foot of Huèrfano Butte.








Photo provided by M. McClaren



By 1941, an unknown photographer documented burro weed and Cholla Cactus popping up, along with Velvet Mesquite trees.












Photo by M. McClaren


In 2007, the grass cover has given way to Velvet Mesquite trees, and Prickly Pear Cactus have replaced Chollas as the dominant Cacti.








The story is truly interesting and you can read the complete article here. 

http://uanews.org/story/plants-adapt-drought-limits-are-looming-study-finds



Further Update (February 8, 2013)



Biologist Richard Halsey of the California Chaparral Institute took a series of dated photos stretching from 1991 to the present. They beautifully illustrate just how the chaparral plant community ecosystem can easily regenerate when left on it's own and the succession of plants which appear in order of importance which also provides their own important role they play during this period of reconstruction. Here is the series.




Photo by Richard Halsey



Post fire March 1991 — at  Del Dios Community Park








Photo by Richard Halsey



Post fire June 1992 — at Del Dios Community Park









Photo by Richard Halsey



Post fire June 1995 — at Del Dios Community Park








Photo by Richard Halsey
Post fire August 2004 — at  Del Dios Community Park










Photo by Richard Halsey


Post fire February 2013  — at 

Del Dios Community Park









Photo by Richard Halsey


Here is a wider view of the mountain in its full post

 fire 
glory, 22 years later. February 2013  — at 

 Del Dios Community Park 
 





For more official information on the Chaparral Plant Community's ecosystem and the misinformation about them, please follow this link -

http://www.californiachaparral.org/chaparralmyths.html





Learn more about the Chaparral Plant Community of Southern California. It's a part of what makes Southern California and it's climate so unique and which accounts for the reason so many choose to move here. Otherwise they'd stay behind in their dense woodland environments up north or back east with it's defining four seasons. This plant community is the reason behind almost every day being a perfect day. Most people around the globe have never appreciated this in their life time. 


These series of chaparral recovery photographs above and the historical ones at the top of this page are another good reason for you to get yourself out into nature and discover a new hobby. Having fun with photography and at the same time documenting something that may even be used in years later from now in future research somewhere. For a change, get your kids involved in such a wholesome and worth while activity. But you may actually have to be a Parent and pull them away from their 'babysitting electronics'  for which fault your bare. Forget that modern day "Time Out" crap, just do it for their own good. Too bad there weren't a great plethora of digital cameras back in the old west pioneer days. How kool would that be to see what we don't see or know about today ? 



Last year my wife and I watched a National Geographic documentary about a young college student who wanted to become a Marine Biologist. His inspiration was the Marine Biologist Jacques Cousteau whose films inspired him in his quest. Indeed, back in the 1960s, Jacques Cousteau's films brought a mysterious undersea world into the living rooms of many a family who otherwise would never have known about such wonders of life in the world's oceans. This young college student teamed up with Jacques Cousteau's grandson, Philippe Cousteau Jr on retracing the exact locations where Jacques Cousteau and his son Philippe Cousteau Sr filmed their first adventures under the Mediterranean Sea off southern France. What they found was disturbing. Instead of the great abundant biodiverse sea life in those 1960s film documentaries, there were nothing but dead zones where the only fish life were about the size of minnows. Most all of the reefs were gone or dead. They showed clips of the old films which looked like some over populated Sea World Aquarium. In the documentary, the young aspiring Marine Biologist lamented that now if he wanted to continue his love of Marine Biology research and learning, he would no longer be able to do it in the wild in many places, but rather by watching older Jacques Cousteau Film documentaries. Anyone else find this pathetic that things would get this bad on Earth ? Do you now see the benefits of historical documentation photography ? Even if it's just a hobby for fun ?






Photo by Murat Draman   - National Geographic


(Interview in English) Philippe Cousteau:

"The Mediterranean Ocean is a dead sea. Well, my grandfather was diving 40-50 years ago. You can go back and see those films and look at that footage. And you go back to the same places today and it's changed so much. And these places with coral and full of life, you go back and it looks like desert under water
."





Photo by Enric Sala  ©2012 National Geographic


Notice the contrast here where fish abound in this part of the Mediterranean in Spain's Medes Islands ? Unprecedented new research turned up healthy ecosystems in well-enforced marine reserves across the Mediterranean. 




There are many other ecosystems on Earth, much like the Chaparral plant community which have been snubbed as worthless or exploited for whatever resources. Even now such a plant community is being demonized and vilified as the reason for all the Mega-Fires which in reality are human error. Learning about the natural world through a biomimicry or biomimetics point of view will go further than this time wasting politico-ideological worldview pimping that is being argued presently by two major sides opposed to each other in time consumption bickering. But time pants on to the end despite this and at some future point it will be game over for the majority of mankind. For those that 'get it', be vigilant by keeping on the watch.


And if you still think I'm over doing it on the photo thingy, check this out:


Imperial College London: "Scientists using holiday snaps to identify whale sharks"




Holidaymakers' photos could help Scientists track  the movements  of giant endangered sharks living in the waters of the Indian Ocean.



Monday, January 21, 2013

Santa Rosa Mountains & Climate Change - Will Anyone Pay Attention ?

University California Riverside
Looking down the throat of Deep Canyon towards Palm Desert and the rest of Coachella Valley below. A view of the landscape where Scientists found plants have shifted uphill for over 30 years. But was this shift in upwards movement an actual climate change phenomena from a once wetter period to the now present drier one ? Well surprise, it's another human component.There has always been some sort of speculation and controversy surrounding the San Jacinto Mountains, and especially the Santa Rosa part of those mountains, as to just how far down and extensive the forest areas once occurred at lower elevations. Some call it a fable and myth, others saying it was thousands of years ago when when the climate was wetter than today and it had a more vegetative state than at present. But the date is almost always pushed very far back.

photo: alltrails.com
Recently I touched on this subject in a post on the Santa Rosa Mountains and the story behind the old  Sawmill Trail  and the man who helped build it Jay Dee McGaugh of Radec (Aguanga) California. To make a longer story shorter, Jay Dee McGaugh said that the road was built to harvest thousands of Jeffrey Pine trees some Forestry Official said were 'Bug Trees' and needed cleaning out. Dee McGaugh , who not only cattle ranched, but also had a heavy equipment business and who was contracted out in the old days for road building, said that the forest then extended much lower than you see it at present. Well, he certainly should have known he was after all, there and an on the spot eye witness. You also have to understand that this man had no political or environmental agenda for saying this, it was simply the facts as he related them to me when I first met him in 1983. As was common back then, no reforestation tree planting program was undertaken back in those days to replace what they had obliterated. That land was pretty much stripped bare and left to it's own regeneration processes for which even today you will still see along that road some stunted Jeffrey Pines which tried to make a comeback. Mostly now it is Desert Ceanothus (Ceanothus greggii) and Redshank chaparral. But I had found even evidence before that period (1930s logging venture?) where there was clear evidence of a one time existing large old growth forest Jeffrey Pine Trees whose stumps still exist much, much lower than even the present Highway 74 near Spring Crest which was at one time referred to or known as the old tourist stop called "Ribbonwood" named after the very abundant chaparral species around there called Redshank (Adenostoma spasifolium). The ONLY reason these stumps still existed in the late 1980s when I first discovered them on a hunch I had of an area once forested, is because they were charred solid by fire which allowed them to resist rot which would have rapidly disintegrated any tree remnants which would have otherwise been logged at such a lower easier accessible location. At least, these old Jeffrey Pine tree stump locations were pockets of woodland areas in among chaparral plant community, which of course today no longer exist. 

Fast forward now to the present, and that's where a recent study was done around 2008 and a reprint of it in August of 2012 & the comparison to a further study by other researchers which does shed some fascinating light on the subject and gives a credible explanation for a different scenario of change in vegetation from tree forest to one presently now more dominated by a Chaparral Plant Community. I find both studies intriguing and exciting, though the early 2008 authors or group are at odds with each other 2012 Research Group in a bit of the usual intellectual spitting contest that science can be known for in these modern times. This should not surprise us as this is characteristic of most of our world's leadership. In this case it is mostly on the part of Anne Kelly and Mike Goulden against Keeley & Schwilk.  In fact, in these studies I personally found both to have credible bits of gold as far as important findings, though they (researchers) may not have seen the other's point of view through the murkiness of resentment which clouds judgement. Well, moving on, here is a link to the older article in Live Science which also appeared as reprints in other online News. I'll explain what I saw in both Researcher's findings and my own personal experience from living in this area for almost 24 years.
http://www.livescience.com/22239-plant-shift-climate-debate.html
Livescience.com

First we have a debate between two studies. The first of the Studies saying plant movement uphill into higher elevations is caused only by climate change and it's the increase in this area's temperature and droughts that have caused the plants in the study to migrate uphill in elevation. Okay makes sense, since we find certain plants not doing so well in warmer temps and drought conditions. The first study was conducted in 2006/2007 by graduate student Anne Kelly and Mike Goulden both of the University of California Irvine. What they did was to retrace a 1977 vegetation survey that covered sites from sea level at the desert floor to high upper conifer forests at elevation 8,400 feet (2,560 meters). Now basically this Kelly & Goulden believed that climate change has caused plants to move further up the mountainside of Santa Rosa as climate has warmed. But as we all know, climate change is more than just warming, it's about extreme events of all types. They look at a couple of interesting phenomena and they looked at the 10 dominant native plant species that have appeared to have made the change higher up Santa Rosa Mountain. Now they say that Fire or even smog played no part in ecosystem changes, though they do acknowledge the historical Cal-Forestry Fire data. But they were wrong, Brush or Forest Fires are a major part in plant redistribution which ALSO has resulted in the localized climate change.  I've already addressed this when I spoke of my experience in observing back in the 1980s the Cahuilla Mountain cloud formation anomalies during the monsoonal rain season each summer and how the phenomena stopped after the well known Diego Flats Fire in 1996 that I wrote about  HERE!  That entire localized situation changed completely after that 1996 fire on Cahuilla Mountain which is just west of the Santa Rosa Mountains. The old growth Trees and Chaparral were removed and the almost engineered looking cloud formation I described in my post almost immediately disappeared and never came back the next few summer monsoon seasons. Okay back to this study, there were some other problems I have with their view of smog pollution and/or fire smoke effects on vegetation which would influence Jeffrey Pine more than any other plants. Here is a quote from the study.
"Some montane regions in Southern California are exposed to high levels of ozone and nitrogen deposition, resulting in increased vegetation mortality. However, five considerations lead us to reject air pollution as the main cause of plant redistribution. First, the Deep Canyon Transect is comparatively distant from Los Angeles’ emission sources, and ozone-related conifer mortality has not been reported in the Santa Rosa Mountains"
Having lived and worked in and around these mountains between 1980 to 2003, I can attest to smog movement by extremely strong prevailing winds from Los Angeles through San Gorgornio Pass into the Coachella Valley for which a possible influence could indeed effect those mountains. I also remember a time when the region west of there in and around Temecula & Murrieta west of Anza Valley had mostly crystal clear days and baby blue skies in those early years, but that all changed to filthy air over time to the present with the building boom. Did they account for this ? No they did not,  because they weren't present and were ignorant of these facts and probably didn't think to interview or attempt to ask these questions of locals which was a loss. No doubt such local residents would be considered not scientifically credible enough, which seems to fit the pattern of many research papers these days. Although attitudes are changing.

Credit: 'Deep Canyon' Blog
Now some other fascinating details in the paper are about rainfall average totals and one of the rainfall charts which shows the historical rainfall averages to the San Jacinto Mountains which were actually less in average between the years 1947-1976 to a increase in rainfall between 1977-2006. Although I have to say these data averages were taken from several reporting stations 75 kilometers away throughout Southern California, and certainly don't reflect the local conditions of these specific mountains. Again, I have to go back to local residents and my own personal experiences with rainfall anomalies in these and any other mountain ranges. Everything is not equal. Some regions have downpours and others get spit on, but they do acknowledge this in another similar paper  HERE!  I've often watched the TV News weather reports with irritation knowing how radically different each location can be. Clearly it's a tough call, but they should have done more homework locally with their own stations at differing location/elevations. Just too many variables to not get accurate specific readings and making assumptions and speculations on these. There was also more lower level snow in the early dates, than in the later. I thought this was interesting because it would be important in that water release by snow pack in those early dates would be gradual and percolate much more slowly, which would hydrate the plant community over a longer period, as opposed to rainfall which would mean immediate runoff and water quickly heading downstream for the Desert's Alluvial Fans or Bajadas Plains on the desert floor.  There is no doubt that they missed some very important points here, but I think the climate change locally speaking was important never the less. Another extremely important event they make no mention of  whatsoever is the historical heavy logging which happened back in the 1930s/40s. Clearly this would influence the upper regions where the absence of  Jeffrey Pines & Oak allowed habitat inroads from other chaparral species which were always present as opposed to anything with climate and prove a more rapid removal and immediate relocation of plants as opposed to climate change over a long time. This would also influence local weather and other lack of cloud formation anomalies or mechanisms which would account for warmer temperatures. 
Here again is the full paper of the study done by Anne Kelly & Jon Goulden.
Rapid shifts in plant distribution with recent climate change
http://www.academia.edu/2009705/Climate_influence_on_shifts_in_the_Deep_Canyon_ecocline_1977-2007
SHIFTS IN THE DEEP CANYON ECOCLINE 1977 – 2007

Photo Credit Calphotos: Pinyon Flats Fire
The more recent study by Dylan Schwilk, of the Texas Tech University, and Jon Keeley, of the U.S. Geological survey and University of California Los Angeles, (which I agree with more) resurveyed the some of the same sites but rather focused on a single plant species instead, Desert Ceanothus (Ceanothus greggii). They found an interesting pattern of this particular shrub becoming less common at lower elevations and more common at higher elevations. This triggered conclusions about the movement of the chaparral plant which may have been due to the brush & forest fire history more than anything else. And yet, while they tended to dismiss or cast some doubt on local climate changes, I am more inclined to add it to the unusual plant rearrangement phenomena. I mean there is no argument about vegetation removal creating desertification patterns. What they did was to study plant ring growth history because these Desert Ceanothus plants are known to not sprout until after a fire. They also followed the same fire history as referenced in the other study which indicates a huge major fire 91 years ago which would put that around 1922 and another major fire around 1947. Sure enough you can check Cal-Forestry historical fire records and the early 1920s and late 1940s had major fires in the Santa Rosa Mtns. Here is a link to this website for fire records:  Cal Dept of Forest & Fire  In fact they have a map on their website with various colours representing different historical date time periods. I believe the later fire burned from Santa Rosa Mountains all along the north face of Thomas Mountain to Lake Hemet which obliterated that entire forest. Only a very few burnt snags remain on that Thomas Mountain in key areas, but this fire was very complete in it's destruction of the ecosystem. Once again, it had a human cause component. Forestry folks always said it was the local Santa Rosa Indians who started that fire, but who knows. Either way the cause was human. Interestingly, they also do not make mentioned of any of the logging up on the north face of the Santa Rosa Mountains along the switched back Sawmill Road trail. Clearly this would have made a difference in their Jeffrey Pine study. There also is no mention of the trees and woodlands around Spring Crest and the Santa Rosa Reservation on both sides of Hwy 74 which would also have been important, even if the trees were in small woodland pockets in among the chaparral which would have been common. Here is the link to their fire hypothesis study.
plosone.org: "A Plant Distribution Shift: Temperature, Drought or Past Disturbance? Dylan W. Schwilk & Jon E. Keeley
Here is the Kelly/Goulden reply to the Schwilk/Keeley Brushfire Hypothesis:
Reply to: Schwilk & Keeley (2012), "A plant distribution shift: temperature, drought or past disturbance?"
This is a pity, Kelly/Goulden were clearly irritated in their rebuttal of the Keeley/Schwilk study for which I most agree with BTW. It is logical and can be verified by not only official fire history, but also eyewitness account by older ones living at the time, but now presently gone. There is also the mechanism factor of plant (trees/shrubs) vegetation removed and if not replaced, causing a change in weather or climate. Vegetation facilitates rainfall, especially during monsoonal moisture summer seasons. The second fire wiped out what re-establishment taking place after that first fire and was coming back to not only the Santa Rosa Mountains, but Thomas Mountain and parts of Eastern Anza area of Burnt Valley and Table Mountain. Forest trees need ample time to mature and produce more seed. There was never enough time lapsed between fires. There are no longer any viable heavy forest cover there anymore, though the evidence is still in existence and I'll write a future post with photos on that later. There are other regions of the planet that also express similar plant movement in elevation have been studied, as this one in the video below around Madagascar. Like the San Jacinto Mountains which have clear distinct life zones which start at below Sea Level to high Alpine Elevations, many of these typical mountains have a change in temperature every few hundred or thousand feet, depending on the circumstance. Micro-climates with both plants and animal species are common. But on average cooler temps mean different life zones. Incredibly, if you take all of these 1000s human caused localized plant destruction and plant community pattern changes and combine them all together around the global, it is clear these have effected the macro-climate patterns around the Earth which is why we have Climate Change, despite what the political debates want to argue.



Here are some interesting facts about the plants studied. Table 1. from the first study by Anne Kelly & Mike Goulden where 10 plants were studied. The second study by Dylan Schwilk & Jon Keeley followed on Desert Ceanothus. Change in cover-weighted mean elevation of ten most widely distributed species in the Deep Canyon Transect Species
Mean elevation, in meters from 1977 & 2006–2007 
Abies concolor (evergreen needleleaf tree)
 http://www.laspilitas.com/nature-of-california/plants/abies-concolor
2,421 meters to 2,518 meters elevation = +96 increase in elevation.

Pinus jeffreyi (evergreen needleleaf tree)
http://www.laspilitas.com/nature-of-california/plants/pinus-jeffreyi
2,240 meters to 2,267 meter elevation = +28 increase in elevation.

Quercus chrysolepis (evergreen broadleaf tree or shrub)
http://www.laspilitas.com/nature-of-california/plants/quercus-chrysolepis
 1,987 meters to 2,033 meter elevation = +47 increase in elevation.

Rhus ovata (evergreen shrub)
http://www.laspilitas.com/nature-of-california/plants/rhus-ovata 
1,457 meters to 1,518 meter elevation = +61 increase in elevation.

Ceanothus greggii var. perplexans (evergreen shrub)
http://www.laspilitas.com/nature-of-california/plants/ceanothus-greggii-vestitus
 1,602 meters to 1,671 meter elevation =  +70 increase in elevation.

Quercus cornelius-mulleri (evergreen shrub)
http://www.laspilitas.com/nature-of-california/plants/quercus-cornelius-mulleri
 1,485 meters to 1,522 meters elevation = +37 increase in elevation.

Larrea tridentata (Creosote Brush evergreen shrub)
http://www.laspilitas.com/nature-of-california/plants/larrea-tridentata
 317 meters to 459 meters elevation = +142 increase in elevation.

Ambrosia dumosa (drought deciduous shrub)
http://www.laspilitas.com/nature-of-california/communities/joshua-tree-woodland
 630 meters to 748 meters elevation = +118 increase in elevation.

Encelia farinosa (Brittlebrush drought deciduous shrub)
http://www.laspilitas.com/nature-of-california/plants/encelia-farinosa
 574 meters to 674 meters elevation = +100 increase in elevation.

Agave deserti (evergreen succulent) 
http://www.laspilitas.com/nature-of-california/plants/agave-deserti
693 meters down to 643 meters in elevation = -50 decrease in elevation. 
Illustration Credit: University of Arizona 
Dominant plant species along an elevation gradient shifted synchronously with one another over a 30-year span that has a concurrent temperature increase, based on a new study by Kelly and Goulden (13). The ranges of the plant species' distributions remained the same, resulting in an overall "leaning" of the vegetation gradient toward higher elevation. At the very least, this clearly illustrates the Jeffrey Pine forest retreat over the historical early time period to the present day.
Another one of the more interesting anomalies in that plant list was the fact that the Desert Agave actually dropped in a lower habitat elevation by 50 meters (164 feet). No mention was ever made or explanation of this strange fact was given. There was a massive fire which hit the entire Pinyon Flats area in the 1990s, but I doubt they never even took that into account. For me the historical forest line in elevation has an intense fascination. I've always hypothesized myself that the Ancient Lake Cahuilla (present smaller Salton Sea) had more than one means of water source than the Colorado River. In the early 1980s when we had heavy yearly rainfall amounts on record between 1980s and 1986, the Deep Canyon Horsethief Creek, Whitewater River, Taquitz & Andreas Canyon Creeks, Palm Canyon Creeks among others had tremendous amounts of water pouring down through them all the way to the Salton Sea and in some cases most of the year. Maybe some valley resident peoples remember all the road and golf course closures back then ? Much of that water ran yearly down those normally dry washes. If in ancient times those forest levels were far lower and rainfall far more plentiful, then these tributaries would have contributed to Lake Cahuilla's water level maintenance. There is evidence for this as well. 

This Spring I'll photograph some of the old charred Jeffrey Pine stumps I found on both sides well off of Highway 74 (Palms to Pines Scenic Route) which is nothing more than Chaparral Plant Community and I'll post them on a separate link and attach this page to them. What is both interesting and sad with both these studies is that both Research Groups are correct in Fire destruction and Climate Change and but in that very order. But clearly these imperfect human 'Egos' got in the way as a result of this incessant obsession with fame, glitter and glory which can be infectious to many in Science today. Clearly I find  Keeley's and Schwilk's study more compelling. Can you imagine what they could accomplish in working and cooperating together as opposed to all this fighting ? It's too bad because many different Research Groups today miss out on a lot of important findings which could lead to rebuilding these ecosystems. While I like the Keeley/Schwilk Study, I was disappointed a bit on the lack of mention of any off the logging operation which harvested large numbers of Jeffrey Pines from Santa Rosa Mountain which also could have also effected climate, though on a localized level, or greater if adding the fire component. - Stay tuned for update!
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Update:  This is an update with regards the subject matter within this post. I have recently documented some out of place plant anomalies I first discovered back in 1984. They are now photo documented and reveal an older forest location of Jeffrey Pine at the foot of Santa Rosa Mountains where no such pines exist today. This is a much lower elevation than even Hwy State Route 74 between Santa Rosa Indian Reservation and the planned housing Community of Spring Crest. This location is specifically explained and easy for anyone to document. Caution, always be careful here - Enjoy
Plant Forensics in Discovering a Climate's Ancient Past

Thursday, January 3, 2013

Mistletoe: Former Demonized Plant Turns Out to be a Great Helper

Photo Credit: Duke University
Mistletoe is more easily identifiable in the Fall and Winter when deciduous trees have lost their leaves. Yet there are numerous other species of Mistletoe which exist on other evergreens, cactus, Chaparral, Eucalyptus, etc. Often demonized and used as an excuse for  timber harvesting and Control Burns, now it appears to be an actual Keystone species necessary for a health Vegetative system and it's occupants.


Wow, who knew it had other uses ? Well, Scientists should have known this all along. At least the ones who are in charge and trust of protecting the natural world and the authoritative control over official policies for responsible the land management. But as with other areas of Science back in the 20th Century, this hasn't always worked out well for the natural world. Government agencies with official oversight of Natural Resources have always managed the landscape from an exploitative money making venture perspective. Now that our natural world is so badly degraded at the start of the 21 Century, it is only now we see the real true value of things that have been either completely lost and not ONLY on the verge of  extinction, but now Science is actually taking a harder look at things assigned negative labels such as a disease, infectious, invasive, ugly, worthless, parasite and so forth. Ultimately, they now have to try to view various components of Earth's Ecosystems from a purposed perspective (something often considered by some as heretical in the past), just what benefits are derived from organisms like Mistletoe deemed worthless, evil or invasive.


Credit: US Forest Service
Words/Terms like these ones here  'invasive' - 'parasite' - 'infection' etc, have often in ignorance done more to hurt our understanding of some organism than to further it. To be honest, Mistletoe in my book isn't any of these and I'll conclude further on down as to why that is so. For more than a century, Mistletoe has been long thought to be a destructive trees murdering organism for which this great harm to human resources must be eradicated. I wanted to comment earlier when the research paper came out by David Watson, a researcher at Charles Sturt University in Albury of New South Wales in Australia, but I was delayed. I really wanted to document & reference for you some of the usual bad forest policies used in the past to eradicate or control what were considered infestations of Mistletoe in regards to Control or Prescribed Burns. But first, here is the latest article came out in the around December 17th 2012. Here is the link and Abstract and my comment after that. (by all means read the entire paper)
The Royal Society: "Mistletoe as a keystone resource: an experimental test"
Abstract:
"Various entities have been designated keystone resources, but few tests have been attempted and we are unaware of any experimental manipulations of purported keystone resources. Mistletoes (Loranthaceae) provide structural and nutritional resources within canopies, and their pervasive influence on diversity led to their designation as keystone resources. We quantified  the effect of Mistletoe on diversity with a woodland-scale experiment, comparing bird diversities before and after all Mistletoe plants were removed from 17 treatment sites, with those of 11 control sites and 12 sites in which Mistletoe was naturally absent. Three years after Mistletoe removal, treatment woodlands lost , on average, 20.9 percent of their total species richness, 26.5 percent of woodland-dependent bird species and 34.8 percent of their woodland-dependent residents, compared with moderate increases in controlled sites and no significant changes in Mistletoe-free sites. Treatment sites lost greater proportions of birds recorded nesting in Mistletoe, but changes in species recorded feeding on Mistletoe did not differ from control sites. Having confirmed the status of Mistletoe as a keystone resource, we suggest that nutrient enrichment via litter-fall is the main mechanism promoting species richness, driving small-scale heterogeneity in productivity and food availability for woodland animals. This explanation applies to other parasitic plants with high turnover of enriched leaves, and the community-scale influence of these plants is most apparent in low productivity systems."
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Wikipedia

What impact does the Dam
of a Keystone Species like a
Beaver play in an ecosystem ?
Mistletoe = Ecological Keystone Species ? This would be a living organism that has the biggest impact on life around it within an ecosystem. But who would have thought that of Mistletoe ? I mean it is often ugly, rangy looking, certainly poisonous. So what possible worth or value  is it ? It's funny, I was reflecting on this negative attitude on this plant and similar attitudes towards other species plants, animals, birds, etc (like various Chaparral Plant Community Species) from a Human perspective and realized that humans treat and judge other humans the very same way. Or is it the other way around ? Could it be that mankind's often inhuman treatment of other cultures, races, class distinctions etc has been transferred over from their abuse of the natural world's resources and that explains the sad state of affairs in our societies as well ? I do believe it's both that reflect the mirror image of each other. But let's get back to examples of other kinds of Foundation Species which will illustrate the importance of the role a Keystone species plays in any habitat and get a better than average understanding of what and how Mistletoe fits just such an important niche in nature. How about a Beaver's Dam ? A Beaver moves into a completely new area and then by his dam building, physically and dramatically changes an entire wide area even well beyond it's immediate shorelines. 

Wikipedia
This impact of a Beaver's Dam building in create a lake or even small pond are huge indeed. Clearly as illustrated above, there are the obvious reasons. But even still, more so even far away from beyond the immediate vicinity of the pond or lake. Underground water tables are raised. Riparian woodlands which will be extensive around the banks will not only provide shelter and other habitat and food resources, but also the fact that their specific nature with regards their root systems in being both Endo & Ecto Mycorrhizal make them perfect water shunts or hydraulic transporters to other species of forest trees and chaparral far away from the water source. That in turn creates further life opportunities elsewhere.

I truly enjoyed reading from the study here, about some of the benefits that Mistletoe actually provides in the plant communities. I've always known about the benefits to birds as far as food and nesting, but the intriguing benefits of Mistletoe leaves to the forest floor was very interesting. Again, who knew ? Who would have thought Mistletoe leaf litter contained further richness for which to effect other life on the forest floor ? So the Mistletoe actually provides more richness in nutrient drop debris, than simply it's own leaf litter. And as far as that label "Parasite", I hate it !!! Why ?  Because the reason is, it's inaccurate of what I would consider a true parasite, you know, one that sucks almost all the life from it's host and gives nothing back ? But Mistletoe is different. scroll back up and look at the colour of that Mistletoe at the top of the page. Notice all the green ? That is Chlorophyll and for what purpose is Chlorophyll used for ? The manufacturing of food. So it's doesn't exactly draw from the tree's carbon stores what it needs, it manufactures it's own.  What it does do is create roots within the tree's branches and trunk and draw water and nutrients. Mycorrhizae however does draw from the plant carbon sugar stores and yet we don't consider it a parasite. Why ? Because it actually increases nutrient and water uptake by the plant by 200% and you can actually see improvement. It actually makes the plant work harder, but more efficiently. So one has to wonder what other things Mistletoe may be giving back to the tree in the way of beneficial Chemical exchanges. We do know that through the mycorrhizal network that plants can make chemical exchange between all sorts of trees and shrubs. So mycorrhizae gets a much nicer word of association through Symbiosis

Credit: ForestryImages.org
Dwarf mistletoe on black spruce in
northern Minnesota, USA
There is no doubt that under specific circumstances, the over abundance of Mistletoe in a tree which may be in a weakened state,  can overwhelm and even kill the tree. Some like the Dwarf Mistletoe which are perhaps not of the Greener variety and colonize pines, maybe have more of a parasitizing nature when out of control caused by imbalances. However, if there is one thing we all do know NOW, the natural world when it's left in a pristine healthy state with all it's various living components for which we NOW know all cooperate and help one another as opposed to the mistaken dogma or doctrine of "Survival of the Fittest", doesn't normally work against itself, UNLESS something gets out of balance. Mostly, if it does, it has a human stain of ignorance shackled by greed and selfishness as a motivational factor. The same could be true, and there is evidence that it is, with much of the mistletoe degradation of forested ecosystems around some places on Earth. At times however, out of control mistletoe can leave clues behind as to why conditions were so favourable for it's excessive spread which has been a result of human mismanagement of the land.  Take for example this photo below. 


Credit: ForestryImages.org
Large clearcut in mistletoe infected jack pine stand in Manitoba. Cut boundaries located well beyond extent of infection. Site chained afterward to eliminate infected understory trees.
http://www.forestry.uga.edu/outreach/pubs/pdf/forestry/mistletoe%20monograph%20pub%2008-25.pdf
 When I hear of certain specific reasons (excuses) made for why trees needed to be harvested to eradicate something or even plans for a prescribed or control burn to eradicate something, I know that as a general rule, some other motive is behind it. While there may be real circumstances where there could be a real need, how or why did such an overwhelming outbreak occur in the first place ? Take a clue from the photo above of the clearcut forest. They said on the forestry link that it had to be done because of the invasive Mistletoe. Really ? See anything odd or unnatural about that photo ? Yes, of course, it's a dead give away. It's not a normal occurrence for Jack Pine or any other species of tree to grow in a monoculture setting which looks more like row crops of a corn field somewhere in Iowa. Clearly, the unnatural circumstance of the Industrial Forestry created in the first place by humans is to blame, but that is not what gets the blame. Mistletoe is the evil villain. The above circumstance also justified taking out non-infected areas also. Open this link below here from the Warnell School of Forestry in Georgia and scroll on down to page 20 view the survey chart which shows the results of three Surveys taken in the U.S. states of Kentucky/Tennessee hardwood forests. The percentages shown for the majority of Mistletoe colonization are mostly tiny to none per species and yet the four highest percentage species listed certainly are not life threatening to the woodlands either. This is because the forest is extremely biodiverse and not monocropped like the Industrial Tree Farm of Jack Pine in the above photo. 
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Juglans nigra 35%Ulmus americana 21%Ulmus rubra 16%Robinia pseudoacacia 11%Prunus serotina   9%Fraxinus americana   7%Acer saccharinum   4%Celtis laevigata   4%Gleditsia triacanthos   4%Ulmus serotina   3%Ulmus thomasi   3%Acer rubrum   2%Carya ovata   2%Celtis occidentalis   2%Maclura pomifera   2%Fraxinus pennsylvanica   1%Liriodendron tulipifera   1%Nyssa sylvatica   1%Quercus alba   1%Castanea dentata   0.6%Platanus occidentalis   0.6%Acer saccharum   0.3%Fagus grandifolia   0.3%Liquidambar styraciflua   0.3%Ostrya virginiana   0.3%Quercus prinus   0.3%Sassafrass albidum   0.3%Ulmus alata   0.3%Quercus muhlenbergii   0.1%
There are numerous Mistletoe species and many of them host specific, which means they prefer one or two kinds of tree. The more biodiverse, the far less problem of an entire wipe out of an ecosystem. BTW, read that entire link. There are some fascinating educational information on Mistletoe life cycle and construct on that paper. Below is a photo of the use of prescribed burns for control. 
Credit: ForestryImages.org

Cut, felled and 'prescribe burn' of supposedly Mistletoe 
infested Lodgepole pine in the United States.
Recently I wrote about the Santa Rosa Mountains which are above overlooking Palm Springs. Sometime back in the 1930s, a switched back trail called the Sawmill Trail was constructed to allow Logging companies back in the 1930s to harvest Jeffrey Pine trees. Talking with the man who built the road, Jay Dee McGaugh, he said the excuse the Forestry gave them for clear cutting the Jeffrey Pines  was that they were all "Bug Trees", which I took to mean they were all infested with some species of Pine Beetle. Knowing the way politics was and has been, one has to wonder if the real truth of the matter was more of a money making venture as opposed to any ecology. Guess we'll never know for sure, but no replanting effort was made and the forest tree line no longer extends lower down Santa Rosa as it once did. Recently another similar Science report has come out and exposed the cause for the global increase of an explosion of Jellyfish populations everywhere around the entire earth. Of course the report doesn't blame the Jellyfish, but does expose the human cause of pollution throughout our planet's oceans for the favourable conditions which facilitate & trigger their rapid increase. My point here is this. There are all sorts of living organism on this planet that are out of balance. Some of the out of balance circumstances even in your own yard's landscape like insect pests, weeds or whatever may be a fault of your own, but unknown to you. Before applying some irresponsible damage control measure by use of other science based innovations like chemicals, should be avoided to see if there is a more ecological solution which would be more viable.
EurekAlert
Common scene of Japanese Fishermen fighting to keep Jellyfish from their nets. These creatures are also consuming the fish they may catch. But will the Fishermen blame government and big business for the off balanced abnormal conditions created by industrial pollution and demand something be done about it ? Or will yet apply another negative label to be attached to a creature who simply responds to genetic instructional instincts as triggered by it's environment for which humans are responsible ?

These two links here are of some of the negative uninformed mentality which rules. Further below are some more interesting links. You can actually Google more info and obtain 100s of other informative links with the same bad science viewpoint towards Mistletoe. In the mean time, when you next go walking on a nature hike, give consideration to those darker green lush patches high up in the tree's branches and give some thought to all the other biodiverse richness of life they provide to the entire system
http://www.fs.fed.us/outernet/r3/publications/documents/dm-fire.pdf
http://www.landandwater.com/features/vol49no6/vol49no6_1.html
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Further Reading References on the importance of Mistletoe
University of Adelaide: "Could mistletoe give the kiss of death to cancer?"
"Beyond pills: Cardiologists examine alternatives to halt high blood pressure" (Mistletoe Extract Used in Chinese Medicine)
Charles Sturt University: "Passions meet in mistletoe book" (2011)
http://www.hiltonpond.org - "MISTLETOE: FRIEND OR FOE?"
http://www.arhomeandgarden.org/plantoftheweek/articles/mistletoe.htm
http://www.floridata.com/ref/p/phor_leu.cfm