High Elevation White Pines

There are significant concerns about the sustainability of high elevation white pine ecosystems. As more high elevation ecosystems are being impacted, there is a threat of diminished western ecosystem diversity, as well as reduced opportunity to understand their components and function more entirely. Some of the concerning threats to high elevation white pine ecosystems include human introduced stressors such as white pine blister rust, fire exclusion, and climate change, and natural stressors such as bark beetles and dwarf mistletoe.

One of the most extensive threats is the non-native pathogen (Cronartium ribicola ) that causes the lethal disease white pine blister rust. Trees infected with the rust fungus develop cankers on the branches and main stem that eventually cause the tree to die. Currently, several management approaches are available to mitigate impacts caused by white pine blister rust yet none have proven to be completely effective and suitable for the low elevation white pines (such as eastern white pine, western white pines and sugar pine); tests have only just begun to assess their potential effectiveness for high elevation white pines.

The combined impact of tree mortality caused by blister rust and bark beetles is likely to have long-lasting impacts on populations of high elevation white pines.

White Pine Blister Rust

Description

Photo Credit

USDA photo by Erika Reiter

A major threat to high elevation white pines and their ecosystems is a non-native fungus (Cronartium ribicola) that causes the disease white pine blister rust. All of the North American white pines are susceptible to the rust. In those species studied, white pines show low levels of resistance and high mortality rates in all cases.

The rust, native to Asia, was introduced to North America around the turn of the twentieth century. Since its introduction, it has spread to 38 states and caused substantial damage and mortality especially in commercially valuable species of white pine. The disease continues to spread into high elevation areas where the effects go beyond the loss of individual trees. The cascading effects on associated plant and animal communities throughout the affected ecosystems have been observed.

Disease cycle

White pine blister rust has a complex life cycle that requires two hosts, a white pine and, most commonly, a currant or gooseberry plant (Ribes ssp.). But recently indian paint brush (Castillija spp.) and snapdragon (Pedicularis spp.) have been discovered to be alternate hosts as well. All species of white pine are susceptible at all ages; however seedlings and young trees are often more easily infected and die more quickly as a result of infection. 

Generally, white pine blister rust spores germinate on the plant surface and grow into the pine through the stomatal openings in the needles or a through a wound. The fungus then grows into the twig. The infected branch will often swell; after a year or more, the rust forms spores that are contained in blister-like sacks that erupt through the bark of the twig or stem. When the blisters rupture they release bright orange colored aeciospores which infect the alternate host, most commonly gooseberry or currant plants. While hosted on these other plants the rust produces basidiospores that are released in the fall and can infect the pines. The rust is shed from the gooseberry or currant plant when the plant naturally drops its leaves in the autumn.

In contrast, one successful rust infection of a pine can persist and expand for years. Once inside the pine needle the fungus grows down to the twig and into the branch and ultimately to the main stem of the tree. The damage caused by the rust killing the cambium causes a canker and girdles the stem which prevents water and nutrients from passing through the canker area. As a result the distal portion of the twig, branch, or stem dies. If the canker forms on the main stem, it will cause topkill and often cause the tree to die.

It can take years for the disease to kill a large tree. During the progression of the disease branch death and topkill can significantly reduce cone and seed production and tree vigor. The pathogen can kill small trees within just a few years. Unlike bark beetles that attack only mature trees, blister rust threatens multiple aspects of the regeneration process by not only reducing available seed but also causing seedling mortality. As a result, white pine blister rust can threaten the sustainability of high elevation white pine stands.

The severity and rate of infection is not uniform across the landscape; due in part to the biology of the pathogen and the conditions required for successful spore production, transport, and germination. The spores can be damaged by dry air; therefore wet, cool conditions during spore shedding can lead to successful infection.

Impacts

There are environmental, socio-economic, ecological, scientific, and aesthetic impacts of the loss of the highly valued high elevation white pines. While the rust will not likely eliminate all high elevation white pines ecosystems, it will impact the species distribution, population dynamics and the functioning of the ecosystems.

Economically, these pines are not typically used for lumber or pulp but have enhanced the beauty of many national parks, wilderness, and wild areas. In central Colorado, over 100,000 people a year pay an entrance fee to visit an ancient bristlecone pine forest in a Research Naurall Area. Currently, stands of dead and dying whitebark pine trees can be seen in several western parks including Crater Lake, Glacier, and North Cascades. This devastation may begin to affect the tourist economies of adjacent communities.

Ecologically, high elevation white pines play a critical role in maintaining a range of wildlife and plant species. As these pines continue to decline, it can affect the diversity of wildlife and plant species that depend on them for food and cover. The large seeds produced by many of these species are and important food source for the Clark's nutcracker, grizzly, and black bear. The decline of pine species will likely affect squirrel populations and the carnivore species that depend on them.

Mortality caused by rust on harsh, steep, dry sites will likely transition these forested sites to treeless areas affecting slope stability, snow retention, and watershed hydrology. On wet sites, the loss of high elevation white pines will alter future forest composition and successional pathways. The ultimate overall result being more homogeneous forests, changes in fire regimes, and reduced wildlife diversity.

Symptoms

Symptoms of white pine blister rust infection may be difficult to spot at first; it may simply appear as small yellow or red spots on a few needles. Usually within a few years cankers can be found on the branches. These cankers will generally appear as a swollen area that may have a greenish - yellow to orange margin. As the cankers mature they will girdle the branch or stem causing death of living tissue beyond that point. The distinctive orange blisters are visible in later spring and early summer.

Some general symptoms of white pine blister rust infection include:

• Branch swelling - Small branches produce a spindle-shaped swelling with a new infection
• Branch flagging - Branches die distal to cankers; needles turn orange and fall off
• Orange Blisters - Blisters of orange spores on cankers during spring and branch swellings
• Cankers - Diamond-shaped cankers on trunks; greenish-yellow to orange margin when mature
• Resin flow - Branches and trunk on advanced infections can have streams of resin
• Chewing - Rodent-feeding on cankers

The symptoms may appear slightly different on each of the high elevation species.
 

Which currant and gooseberry species are the best alternate hosts for white pine blister rust?

There are dozens of species of currant and gooseberry (Ribes sp.). Some are more susceptible to infection by white pine blister rust than others. Therefore, recognizing Ribes by species and understanding their susceptibility to infection is useful in assessing the hazard of white pine blister rust infection to populations of white pines. Currant and gooseberry abundance and distribution are extremely variable. Consequently, this question cannot be address in a universal way. 

Fire Exclusion

Fire exclusion is the policy of trying to eliminate fires from the landscape using fire suppression techniques. Fire exclusion has had a diverse and cascading effect on the high elevation landscape. The high elevation white pine ecosystems have evolved with fire and therefore are dependent on fire to maintain their dominance, diversity, and presence on sites.

After a disturbance such as a fire, the plant community on the site changes over time in a process called succession. Plant species that can tolerate the exposed conditions become established first. Over time these species grow and provide shade and protection for other more shade tolerant species to become established on the site. As these shade tolerant species grow, they shade out the species that colonized the site first, the early seral species, and the late-seral species dominate the site until the next disturbance reinitiates the process. High elevation white pines are often the early seral species that establish after a fire. Some of the white pines species have a competitive advantage because their seeds are dispersed by Clark's nutcrackers that transport seeds long distances and cache them in newly burned areas.

With fire exclusion, many high elevation communities are shifting from early seral, shade intolerant tree species to late seral, shade tolerant species. Without the openings caused by fire there are fewer opportunities for the establishment of the high elevation pines and therefore high elevation white pines become a smaller component of the forest.

Bark Beetles

The mountain pine beetle (Dendroctonus ponderosae) is a native insect that has coevolved as an important ecological component of western forests. The beetles bore into the bark of the pine host and can cause the tree to die within a year or two. The colder climate associated with high elevation pines has generally been too extreme for mountain pine beetles to thrive, even though these pines are suitable hosts. There is documented evidence of previous mountain pine beetle outbreaks in high elevation five needled pines, particularly whitebark pine. In some cases, beetle populations have increased in lower elevation lodgepole or ponderosa pine stands and moved into adjacent, higher elevation five-needled pine stands. In other cases, favorable stand and climatic conditions have contributed to beetle population increases.

Today, epidemic outbreaks of mountain pine beetle in high elevation whitebark pines (Pinus albicaulis) stands has become an increasing concern and a contributing factor to the decline of this susceptible host type in some locations. A combination of factors may be responsible for these unprecedented attacks, however, more information and research is needed about mountain pine beetle ecology in high elevation sites.
Recently, the beetles have been noted in forests at elevations above 10,000 feet. Some believe that as ambient air temperatures increase, the high elevation forests will be challenged more frequently by bark beetles.

Another factor associated with the recent increase in beetle infestations in high elevation forests may be fire suppression tactics resulting in a greater abundance of dense late successional forests. This provides more favorable stand and tree conditions for the beetles resulting in increased scale and frequency of beetle infestations.

Beetles prefer dense stands of older and larger trees; which results in abundant high-elevation pine tree mortality of the susceptible host component. These same trees often are the primary cone producing trees within these high elevation sites. Reduced seed production can impact regeneration capabilities and wildlife that depend on those seeds as a vital food source. Unlike white pine blister rust however, bark beetles do not affect the viability of young seedlings or saplings.

Other beetle species have been observed in high elevation five-needled pines, the impacts of which have been generally localized. For example, Pityophthorus beetles have seen in whitebark and foxtail pines (Pinus balfouriana). Ips beetles and red turpentine beetles have been seen in whitebark pine. Some cone and seed insects as well as numerous twig beetles have also been observed in the high elevation five-needled pines.

Climate Change & Climate Variability

There are substantial concerns that greenhouse gas induced climate changes will impact high elevation areas. Conflicting predictions obscure certainty on what may occur under future climate conditions. However, in all cases, elevational shifts in vegetative composition are expected. Many scenarios forecast a loss of native high elevation subalpine forests; as other species disperse up the mountains, the current high elevation species will eventually get squeezed off the mountain tops.

The rate of these types of changes would more than likely be slow and subtle, given the longevity of the high elevation pines. The mature trees are less sensitive to environmental conditions than their seedlings. Future climatic conditions may prevent the survival of seedlings of high elevation species where they once were abundant.

Warming temperatures may result in increased mountain pine beetle activity. Mountain pine beetles that were once restricted to lower elevations because of low temperatures at high elevation may move into higher elevation areas. As temperature increases the probability of outbreaks at high elevation may increase.

This was demonstrated in the 1930s in Idaho, when a decade long warming period of temperatures more than 4.5 degrees F above average caused significant mortality by mountain pine beetle in whitebark pine at elevations up to 10,000 feet. Today, Mountain Pine Beetle is aggressively attacking whitebark pine which grow at elevations of 5,000 to 10,000 ft in the western U.S. and British Colombia. Other climate driven variable such as drought and fire can stress trees and make them more vulnerable to insect attacks.

Mistletoe

Several dwarf mistletoe species (Arceuthobium spp.) are damaging parasites to high elevation white pines; some have caused severe damage in certain locations. Limber pine dwarf mistletoe (Arceuthobium cyanocarpum) is of particular concern for all of the high elevation white pines. Heavy mistletoe infection results in reduced growth rates, reduced cone and seed production, and a loss of vigor.

Other dwarf mistletoes species observed on high elevation white pines include:

• Western spruce dwarf mistletoe (Arceuthobium mucrocarpum)
• Southwestern dwarf mistletoe (A. vainatum ssp. crytopodum)
• Lodgepole dwarf mistletoe (A. americanum)
• Larch dwarf mistletoe (A. tsugense ssp. mertensianae)
• Western dwarf mistletoe (A. camylopodum)
• Hemlock dwarf mistletoe (A. tsugense) 

Other Stressors

Other stressors of high elevation pines include needle casts and blights, seed and cone disease and/or insects, and stem and/or root decays. Although these stressors may not pose a large threat to white pine ecosystems, in great quantity any one of these can weaken the natural defenses of a tree and make the tree more susceptible to other damaging agents.

• 

  Needle casts and blights: A variety of different needle casts and blights have been observed on high elevation white pines. Very little is known about these diseases and the impact that they have on these species. Although the symptoms vary greatly, they may appear as chlorotic (yellow) spots on the foliage or the needles can brown and be shed (cast) early as a result of infection. The rate of development is variable but is favored by warm wet weather.

• Seed and cone disease and/or insects: High elevation pine cones and seeds are exposed to insects and diseases that reduce cone and seed production and diminish the natural regeneration capacity.
  • Some insects of cones and seeds include:
    • Cone moths/worms (Dictyctria spp. and Eucoma spp.)
    • Cone beetles (Conophthorus spp.)
    • Seed chalcids (Mefastigmus spp.)
    • Seed bugs (Leptoglossus spp.)
  • Seed and cones diseases include:

    • Seedborne fungus (Siroccocus stobilinus)

       

Research and monitoring efforts are currently underway related to high elevation pines and threats that jeopardize them. Past research, monitoring, and experience have contributed significantly to our understanding and ability to address threats. However, much more work is needed to increase our ability to sustain, protect, and restore these unique ecosystems.

The research and monitoring that is being carried out is multidisciplinary with many contributions coming from various areas including ecology, plant physiology, genetics, plant pathology, entomology, meteorology, silviculture, and ecosystem restoration studies among others.

There is a pressing need to more fully integrate information from many areas of study to enhance our understanding and ability to respond.

Genetics Research

Rust resistance screening and breeding

Rust resistance screening projects estimate frequency of rust resistance in a population and/or identify individuals and families that have genetic resistance to the rust. This information can be used to understand why some individual trees have not developed white pine blister rust under natural conditions and enables scientists to distinguish which trees have escaped infection and which are in some way resistant to infection and why.

One focus of rust resistance screening is to identify the types of genetic resistance naturally present in white pine forests. Once resistant

individuals are identified researchers can study more in depth the genetic traits and/or mechanisms that help these trees resist infection or survive with the disease. These resistant individuals can be used in breeding programs. Past studies of low elevation white pine species indicate that several different mechanisms can be present in resistant trees.

Another aspect of this work is developing rust resistant trees while retaining the genetic diversity within the species for use in restoration efforts. Trees that demonstrate a mixture of resistance mechanisms are bred in seed orchards. This breeding work can help to further increase resistance, and seed from these resistant trees can help meet the restoration and reforestation needs. Information gained in these studies can be used to understand why some individual trees have not developed white pine blister rust under natural conditions and enables scientists to distinguish which trees have escaped infection and which are in some way resistant infection and why.

Additional genetics related work

Genetics of Ribes: Rust resistance screening and breeding continues to be done with the alternate host species of white pine blister rust, currants and gooseberries (Ribes).
Genetics of white pine blister rust: Some scientists are examining genetic variation in the rust fungus including the potential for new lines of the rust with differences in virulence, aggressiveness, and adaptation to different climates.
Linkages of genetic resistance to other important traits and factors: There are efforts to evaluate the relationship and linkages of resistance mechanisms to important survival and growth traits as well as identify environmental factors affecting these characteristics.

Interactions of resistance with other threat agents: Some researchers are assessing the relationship of other damaging agents like bark beetles and dwarf mistletoe with rust resistance.

Colonization & Regeneration Research

Some scientists are studying the conditions and factors leading to successful regeneration and/or colonization of these high elevation white pines. It is known that seedlings of these pines are adapted to growing in intense conditions such as the interior of burns or places with extreme site and climate factors. Yet, there are still many questions about what constitutes favorable regeneration sites.

Some of the major factors that scientists are interested in understanding more about in relation to regeneration and colonization of high

elevation white pines are:

• Factoring affecting seed production
• Frequency and location of regeneration
• Types of disturbances that support regeneration
• Impact of soil nutrients and water interactions
• Effect of competition from other species
• Influence of climate and habitat on regeneration
• Influence of macro and micro site factors
• Impact of fire history
• Influence of stand age structure
• Research on planting protocols and best practices
• Feasibility of direct seeding

Studies on these topics are essential to increase our ability to develop guidelines for silvicultural treatments to promote white pine establishment and develop techniques to successfully regenerate species at high elevation, naturally, or from nursery stock or seeds.
 

Seedling geographic patterns and local adaptations

Researchers are trying to gain a better understanding of local adaptation in high elevation white pines. This involves measuring and quantifying variation in growth and physiological traits among different seed sources. One way of looking at this variation in traits is through seedling common garden studies. Gardens can be used to assess range wide genetic variation in quantitative traits that may reflect local adaptation. Ultimately this information can be used to assess transferability and limiting factors for movement of high elevation pines while setting some appropriate seed transfer guidelines for restoration planting to avoid planting trees in sites to which they are not adapted.

Pathology Research (Diseases)

Many studies are focused directly on increasing our understanding of the white pine blister rust pathogen and it's hosts. This may involve trying to quantify the relationship of the pathogen to the various high elevation white pine hosts in terms of the degree of harmfulness (virulence) and specific patterns in each host. Scientists are also interested in how the pathogen adapts to unique environments, especially those found at high elevation. 

Pathogen host species

Ribes - Scientists are engaged in ventures to understand the role of currants and gooseberries (Ribes ssp.) in blister rust incidence and severity in high elevation white pines. Some specific efforts include:

• Better understanding of the role and mechanics of Ribes in maintaining and spreading blister rust through examination of Ribes specific ecology, distribution, and phenology in relation to other important factors.
• Explaining variation in Ribes susceptibility to blister rust infections by species and region and developing plants that will resist infection.
• Creating more reliable methods for identifying white pine blister rust on Ribes species.
• Determining the impact of fire, prescribed burns, thinning, and other management or restoration activities on quantity and species of Ribes that regenerate  

Other hosts - Most commonly the life cycle of white pine blister rust requires alternation between white pines and currant and gooseberries (Ribes). Some other plants species have been found to serve as alternate hosts for white pine blister rust. Some examples include hemiparasitic members of Scrophulariaceae family like Castilleja and Pedicularis.

Pathogen spore dispersal

One area of specific research is looking at the favorable wind patterns and ground conditions that contribute to rust dispersal over short and long distances. Understanding how and when spores are dispersed is helping to explain how the disease moves and can help to calculate where the disease may infect trees in the future.

Meteorological influences of infection and spread

Scientists are moving towards a better understanding of how weather, temperature, precipitation, soil moisture, elevation, and humidity factors contribute to the occurrence or intensify the impact of threats like bark beetles or blister rust. Weather stations are a useful tool to assess and monitor meteorological conditions.

Research on Bark Beetles 

Researcher are conducting a variety of studies to gain a better understanding of bark beetles in high elevation systems. Some studies have looked at the distribution of attacks in relation to whitebark pine restoration treatment areas. Other studies are looking at potential range shifts under climate change and the implications for bark beetle infestations in the future. 

Dendrochronology

Dendrochronology research is the study of past events and climate change by comparing the consecutive annual growth rings of trees. The high elevation white pines, especially bristlecone pines, are among the oldest living things on earth. A single bristlecone pine tree can live to be thousands of years old, therefore contributing an extraordinarily long chronology of tree ring information.

Tree ring analysis has and continues to be used to draw conclusions about pollution, disease, fire, and even temperature and precipitation cycles from the past. Information gathered from bristlecone pines through tree ring analysis has been instrumental in the recalibration of the Carbon-14 dating system. Bristlecone pines have served as historical record to support conclusions made through other means such as pollen information, sediment cores, archaeological information, and more.
 

Monitoring

Monitoring refers to collecting information in a systematic and ongoing fashion. There are many uses for monitoring high elevation white pine ecosystems both in advance of major catastrophic events and after.

Monitoring data can give an account of the status of the ecosystem at the time of measurement. Past measurements compared to current are useful contrasts for assessing trends. In addition, the information can be analyzed to determine the ecological and economic impacts of changes associated with threats or natural processes.
In order to collect information in a more uniform and meaningful fashion, some scientists have developed a set of standards for specific types of monitoring. This helps to standardize and collect a more cohesive body of information. Monitoring protocols for whitebark pine have recently been developed. 

Examples of applications where monitoring is, or could be, used are:

• To determine the severity of impacts of threats on high elevation ecosystems
• To assess tree survival rates in relation to rust, beetles and dwarf mistletoe and other threats
• To assess changes in general forest conditions
• To measure rust occurrence, spread, and intensification behavior
• To prioritize areas for restoration
• To assess the outcome of restoration efforts 

Potential future applications of monitoring include assessing the survival of natural regeneration compared to genetic resistant seedlings.
This fundamental information collected from the field can be used in conjunction with aerial and remote sensing techniques. 

Aerial survey and remote sensing

Remote sensing is a way of collecting information about an area through the use of airborne equipment and techniques such as photographs from aircraft and satellite. This method can be a very cost effective and efficient way to assess large areas, especially those that are extremely hard to access.

Remotely sensed information together with ground verification has proven to be an excellent monitoring tool to assess trends on a landscape level. For instance, in the Colorado Rocky Mountains, natural resource professionals are carrying out a remote sensing projects to look at areas of concentrated limber pine mortality. 

Comparing data from aerial surveys to other remotely sensed data and field data can help managers understand geographic range and spread of threats such as white pine blister rust infections so that they can more efficiently and effectively plan interventions.

Hazard criteria, models, and risk maps

Identifying hazard criteria is an effort to describe factors that contribute to the probability of occurrence, the severity, and/or the geographic extent of a given threat like white pine blister rust, drought, or a bark beetle infestation. Some hazard criteria that have been identified for blister rust infections at high elevation include:

• weather
• climate conditions
• elevation
• topographic position as well as the distance and proximity of Ribes
• water sources
• current infections

Hazard maps are frequently used to display hazard identification data. Maps help to describe what areas may be most vulnerable to a given threat. They also serve as an excellent tool in prioritizing areas for monitoring and selecting sites for research or restoration projects. Hazard maps can be critically important in management planning and decision making at local to national scales.
Estimations and predictions through quantitative analysis of risk criteria can help describe potential outcomes, losses, costs, increases in intensity, etc. There are many applications for models and the output is quite varied. They can be used to assess the long term ecological and/or economic impacts that may be sustained in a geographic area over a given period. They can also be used to select the best sites for planting and maintaining white pines.

Monitoring database

As more and more information is gathered on high elevation white pines a greater need arises for stable, reliable, and uniform data management systems. This effort has culminated in the National Whitebark Pine Restoration Plan geospatial data inventory by the Whitebark Pine Ecosystem Foundation.

Although high elevation white pine forests are often physically remote, they have not escaped the impacts of human-caused stresses such as introduced non-native pathogens, climate change, and fire suppression. Mortality of high elevation white pines and change in their ecosystems is a reality. These changes are being caused by a combination of factors including, but not limited to, white pine blister rust, mountain pine beetles, dwarf mistletoe, and advanced ecological succession due to fire exclusion.

High elevation white pine forests may not remain as we know and enjoy them today without long-term active management intervention. Innovative strategies, improved information, and the consensus of a diverse constituency are all needed to assure these valued ecosystems are sustained into the future.

The management option chosen for a location depends on site-specific factors and objectives. Management intervention objectives can include:

• Preserving existing high-value trees
• Restoring ecosystem functions to forest sites that have been highly impacted by threats
• Sustaining ecosystems functions and preparing the landscape for threats where impacts are still at low levels or not yet present

As with all forest management, frameworks are used to develop effective strategies on a case-by-case basis. Management decisions based on locally relevant information are most likely to be effective, find support, and persist over time. Not all management options may be appropriate in all high elevation sites. Some areas, like designated wilderness areas, have constraints on management intervention options. 

Factors currently being considered in high elevation white pine management efforts include:

• The area's management direction
• The current state and extent of threat to the resource
• The ecosystem/site characteristics
• The involvement and collaboration of all invested individuals and groups

Resources are being developed to guide inventories, risk assessment, treatment design and implementation actions. There is much potential to learn from low and high elevation ecosystems that have already been impacted by these threats. Information may not be directly transferable among ecosystems, however insights from past experiences and restoration efforts are and will be valuable. Similarly, information from intact areas can provide baselines and further understanding of healthy ecosystem function for heavily infected areas. Managers, researchers, operational professionals, and interested public groups working together and sharing their knowledge and perspectives will aid the development and implementation of effective management options to sustain and restore these ecosystems for future generations.

Management Strategies

White pine blister rust management

The long-term sustainability of high elevation ecosystems in the presence of the rust will depend on the level of genetic resistance in the populations and the ability of the trees to grow, reproduce, and reforest an area after disturbance. Therefore, the overarching long-term goal of management is to increase the level of rust resistance in the populations. More than likely a combination of strategies will be most effective in developing, refining, and implementing effective management options to sustain high elevation white pine ecosystems in the presence of white pine blister rust. For instance, prepare the landscape before infection by creating diverse age class structure; promote natural regeneration from resistant trees after infection; and augment, if needed and available, with artificial regeneration of selected genetic-resistant seedlings. Since many management strategies are currently untested, site-specific treatments are experimental at this point. Therefore, it is strongly encouraged to work closely with forest health specialists in developing and implementing treatments.

Preserving high-value trees

A high-value tree may be an individual that is integral to a campground, cultural site, or residential or commercial landscape or otherwise has characteristics that are deemed valuable such as resistance to other pests or pathogens, historical/cultural significance, extreme age, or morphology. For a tree of this type, survival of the individual is paramount and its ability to produce seeds for wildlife or reforestation is secondary. In these cases, removal of the infected portions of the tree through pruning before the disease compromises the tree may be a management option.

Other high-value trees could be any individual with rust resistance. For a tree of this type, survival of the individual is paramount because of its ability to produce seeds for wildlife and reforestation in the presence of the rust. These trees should be protected from other damaging agents such as mountain pine beetle, wildfire, dwarf mistletoe, etc.

Pruning

A strategy for local short-term management of white pine blister rust in high-value/use locations such as trailheads, campgrounds, cultural sites, and residential areas, is to prune/remove infected branches. This approach is limited; it can be used to keep individual trees alive, yet it does not promote the development of rust-resistant or rust-tolerant trees on the landscape. 

• Pruning infected branches can prevent white pine blister rust infections from spreading into the trunk, where it will girdle and kill the tree.
• Another benefit of pruning lower branches is that it will increase air circulation and sunlight penetration to the lower portion of the tree, therefore decreasing the most favorable conditions for blister rust infection to occur.

Canker pruning

As a conservation strategy, pruning is very labor intensive and may not be feasible over large areas of the landscape. It is best used to save high-value individuals and is not a practical option for increasing the long term sustainability of high elevation forest stands.

Chemical Control 

Currently there are no chemical methods to control white pine blister rust.

Promoting natural regeneration

Restoration of impacted sites may include augmenting the impaired regeneration cycle and accelerating the establishment of rust-resistant trees such that the ecosystem over time can become self-sustaining in the presence of the rust. Actions can include promoting natural regeneration if the seed supply is adequate and supplementing with artificial regeneration using rust-resistant seedlings.

In the early stages of infestation or in areas that have some trees with heritable rust resistance promoting natural regeneration from those resistant trees will increase the frequency of resistance on the landscape.

Fire

High elevation white pines regenerate on disturbed sites more successfully than within intact forests; stand-replacing and mixed-severity fires are the most common disturbance that promotes regeneration in these species. Widespread fire has resulted in fewer regeneration sites and more competition for high elevation white pines. 

• Some experts believe that the maintenance of native fire regimes is the single most important management action to ensure conservation of high elevation white pines. Allowing naturally-ignited fires to burn uncontested when appropriate, or strategically ignite areas to remove fire-intolerant species in a responsible manner may be beneficial to these ecosystems. The burned areas provide conditions suitable for successful natural regeneration of white pines. In due course, this serves to improve individual tree health resulting in more seed production and increased ability to fend off native pathogen and pest attack.
• There are various prescribed fire techniques that can be implemented. Research has shown that on some sites Ribes ssp. populations proliferate after a fire and may therefore increase the blister rust hazard; researchers are studying this trade-off to help decision makers.

Silvicultural thinning

Tree cutting/thinning can be used on a local scale to mimic the effects of natural disturbances or augment fuel loads for prescribed fires. There are various cutting techniques that can be adapted to specific site conditions and desired outcomes.

• When human structures and infrastructure are dispersed throughout the high elevation white pine forests, prescribed or natural fire is often not a viable option. Tree cutting can be used as an alternative to recreate forest conditions that were historically common after major disturbances like fire.
• Commonly, thinning involves removing other conifers in small patches and leaving behind cone-producing white pines. These openings are located strategically in areas where sufficient white pine seed sources exist to produce regeneration. Coincidently, these openings can also provide and improve wildlife habitat.

Supplement with artificial regeneration

If the disease has impacted the stand such that few cones and seeds are being produced, providing regeneration opportunities may not be enough. The process of planting seedlings into an area is called artificial regeneration. Seedlings are grown in a tree nursery and transplanted into the field. Sites occupied by high elevation white pines are often dry and harsh, and it may prove difficult to achieve successful establishment of transplanted seedlings. However, this strategy may be the only option in situations where mortality from rust is high and natural regeneration fails to produce a substantial amount of naturally rust-resistant seedlings. When there is not a sufficient rust-resistant seed source, artificial regeneration is an important and vital component of a high elevation pine conservation effort. Depending on the management objectives and the source of seeds to produce the seedlings, artificial regeneration can be used to:

• Speed reforestation after a disturbance
• Change the species composition of the next generation of trees on that land
• Improve the quality of the existing species on the land.

In the case of blister rust and high elevation white pines, the first and third objectives would apply. Through thinning or prescribed fire, openings in the forest can be created and the improved seedling stock with resistance to the rust can be outplanted.

Identifying improved seedling stock with rust resistance

In areas that are heavily infected with blister rust, there may be individual trees that have fewer cankers than others - these trees are suspected to have resistance to the rust and are called "phenotypically resistant" or "plus" trees. If the resistance is heritable, then seedlings grown from the seed of plus trees would also have some resistance. Confirmation of heritable rust resistance can be determined through scientific study and screening and would further increase their value. Seed from plus trees in the field can be used in direct seeding efforts or to generate seedlings for outplanting in the rust-impacted areas near the plus trees.

• Once identified, these rust-resistant trees are high-value trees and protection from other stresses may be warranted.
• In areas not yet impacted by blister rust, rust-resistant trees can be identified through screening of their seedlings using artificial inoculation studies. This work has begun for some species.

Developing improved seedling stock with rust resistance

Through the breeding program, where the pollen from one plus tree is used to fertilize the cones of another plus tree, seeds with greater resistance to the rust can be developed. The resistant seed can be grown in orchards and the seeds from those trees used for artificial regeneration. This approach has been used successfully for lower elevation white pine species, however its application for high elevation white pine species may be more problematic. Challenges for developing seed stock for high elevation pines include:

• Resistant trees have not yet been identified for all the high elevation white pine species
• It takes 30-50 years for a high elevation white pine seedling to mature to produce a cone

Cone & seed collection

Seed collection supports several strategies used in managing the threat from white pine blister rust. Cones and seeds are collected from healthy high elevation white pines for planting, gene conservation, and rust-resistance screening programs.

Seed collections require effort and skill and should be taken on by professionals with the necessary resources and knowledge of cone biology and the collection planning process. Poor planning can lead to injury to the tree, cones, or collector. Choosing regions and individual trees to collect seed from must be done carefully. The valuable seeds that are collected must be stored under environmentally-controlled conditions to retain viability for future applications.

Mountain pine beetle management

Mountain pine beetle is a natural pest of white pine forests. While beetle kill is a natural process that benefits forest ecosystems by opening the canopy and providing snags for cavity-nesting birds, when the beetle populations grow to epidemic levels and interact with climatic changes, this pest can become more invasive and expand its range and impacts. The beetles usually hit larger trees and weakened trees first, yet, during an epidemic, all mature trees in a stand can become victims. In contrast to blister rust, mountain pine beetle does not infest and kill seedlings and young trees such that natural regeneration of an impacted forest can occur. However, the combination of blister rust with a mountain pine beetle epidemic can be particularly damaging since both pests impact mature trees and therefore seed production, the beetles can kill the few rust-resistant mature trees, and the rust will kill any seedlings that remain or become established. Forest recovery after this combination of impacts will likely require active management intervention.

Management tools to control impacts caused by mountain pine beetle include chemical sprays, tree removal, thinning, and other approaches. As with all intervention frameworks, guidelines may be revised periodically and one should consult with a forest health specialist for the latest advice and methods.

To prevent the growth of beetle population to epidemic levels, there are two approaches: reduce the beetle population and reduce the susceptibility of the forest. The combination of white pine blister rust and mountain pine beetle is particularly threatening to the high elevation white pine ecosystems. Few trees have resistance to the rust, and they can easily be lost due to mountain pine beetle.

Reducing the beetle population

Beetles multiply in the tree and then fly to a new tree and the cycle repeats itself. Killing the larvae in the tree before they turn into winged beetles can be an effective way to control the population when the populations are small. The infested trees can be cut and the bark peeled off to expose and kill the immature beetles. Alternatively, the infested tree can be cut into sections and exposed to the sun to heat and kill the larvae inside. Guidelines exist for these options, and one should consult with a forest health specialist for the latest advice and methods.

Reducing the susceptibility of trees and the forest to impacts 

Healthy trees have defenses to mountain pine beetle, therefore providing optimal conditions for tree health can reduce impacts. Mountain pine beetle also prefers large trees such that a younger stand may be less susceptible to attack when the beetle populations are small. To reduce impacts, forests can be thinned to produce a forest of varying tree ages. Thinning will often increase the health of the remaining trees and further increase their defenses to the beetles. This approach has been used in forests of other tree species but not yet for high elevation white pines. Since the high elevation white pine forests are often low density, it is unclear if thinning would produce the desired effect. When beetle populations are large, the beetles can attack both healthy and small trees.

Protecting high-value trees

Trees with blister rust resistance or those of cultural or economic importance may warrant special protection and management considerations when threatened by beetles, including: 

• Chemical sprays - Applied directly to the main stem of a high-value tree, chemical sprays can reduce the success of beetles entering and infesting the tree. The chemical must be applied each year before the beetles fly. One should consult with a forest health specialist for the latest recommendations for chemical treatment.
• Biochemical detractants (pheromones) - The beetles produce chemicals called pheromones which are used for communication. When a tree is initially hit, the successful beetles emit a pheromone that attracts other beetles to that tree; when the tree is fully occupied by beetles, a different pheromone is released that repels new beetles from boring into that tree. The pheromone that repels beetles can be produced (synthesized) in a laboratory and packaged in envelops. Research is currently underway to assess if these envelops, when stapled to the high-value tree, can prevent beetle attacks.
• Removal of nearby beetle-infested material - Beetles multiply in the tree and then fly to a new tree, and the cycle repeats itself. Killing the larvae in the tree before they turn into winged beetles can be an effective way to control the population when the populations are small. Removal of the infested trees near the high-value tree before the beetles have flown can reduce the likelihood of the high-value tree being hit. 

Dwarf mistletoe management

• Mistletoe-infected trees should be removed from a stand where natural or artificial regeneration efforts are being conducted as mistletoe infections can be lethal to young trees.
• Mistletoe seeds are hydraulically-expelled from the fruiting parasite and can easily fall on understory trees and young seedlings and saplings. Infected tree removal will reduce the risk of further infection in a stand. The sticky seeds can also catch a ride on birds; as a result management of mistletoe may require intervention at scales greater than the target stand.

Managing advanced succession

Succession is the process of forest recovery after a disturbance. In high elevation white pine stands, the white pines are the pioneer species that become established immediately after a disturbance, including after wildfire. In the absence of fire or forest management, other species such as subalpine fir and Engelmann spruce become established in the shade of the white pines. Over time, the spruce and fir trees get larger and can shade the white pines, potentially causing the white pines to die out or become a smaller component of the forest. 

Due to decades of fire suppression, many areas that are good habitat for high elevation white pines are now dominated by spruce and fir. Stands in advanced successional stage tend to be dense and prone to high-intensity fire, which becomes another threat for high-value and blister rust-resistant white pine trees. Some strategies to manage succession and favor high elevation white pine trees and populations include:

• Managing competition - Removal of the competitive, shade-tolerant trees around high-value white pines to reduce sharing and increase the resources for high-value trees. This treatment will likely increase the health and vigor of white pines, but more research is needed to understand best practices and impacts of competition removal in different situations.
• Reducing forest fuels around individual high-value trees - Clearing of the duff layer and/or reducing the built-up debris around the base of high-value white pines can increase the likelihood of survival in the event of a catastrophic wildfire.
• Silvicultural fuels reduction treatments - Mechanical treatments can reduce overall tree density, reduce competition, and/or create openings for regeneration. These treatments may enhance white pine vigor and growth as well help white pine population survive during catastrophic wildfire. Again, more research is needed to understand in which situations and environments fuels reduction treatments are most beneficial.
• Prescribed and intentional fire - Reintroducing fire or allowing low-intensity wildfires to burn in these habitats will create a mosaic of open and forested patches thereby providing open areas for white pines to become established.

Proactive Management Strategies

Sustaining ecosystem integrity and preparing landscapes for infection

The primary objective of proactive management is to prepare white pine populations to be able to better handle known threats to high elevation white pines. 

Blister rust

We know that extreme site conditions and high elevation do not reduce the susceptibility of high elevation white pines to threats like white pine blister rust. Some areas already demonstrate the devastating potential of this threat to alter the landscape. In other locations, blister rust is still at low levels or not yet present. In the latter case, proactive strategies, such as conducting blister rust screening and developing rust-resistant seed sources, may help to increase overall health and resilience in these forests and mitigate impacts once the pathogen invades.

Bark beetles

Any intervention that might increase the health and therefore the defenses of a tree to bark beetles will reduce impacts when the beetles invade. Reducing competitors, whether they are herbaceous plants near the base of the trees or nearby trees, may increase the defenses of high elevation white pines to beetle attacks. More research is needed to determine the effectiveness of such a treatment.

Landscape heterogeneity

Restoring the natural fire cycle and/or using silvicultural treatment in these ecosystems will provide the mix of successional stages on the landscape to promote species diversity and health of high elevation white pine ecosystems. Landscapes with a diversity of species, age-classes, and structures will be more resilient to future threats and disturbances overall.

In order to develop proactive management options, it is critical to collect and integrate information from many disciplines. For instance, information is needed on pathology, genetics and ecology of both the rust and the pines. Even though much information is still lacking, using what we do know and striving to collect new information will help in devising strategies to sustain white pine ecosystem function and maintain the species' existing distribution.

Promote opportunities for natural regeneration

Creating small regeneration sites, using fire or silviculture, before blister rust or beetles arrive will result in mosaic of patches and openings. The undisturbed areas would sustain ecosystem functions and the opened areas would provide sites for the young trees with rust resistance to establish after invasion of white pine blister rust. The age-class diversity on the landscape will promote early identification and selection of rust-resistant trees that are well-adapted to the site. Supplementing natural regeneration with artificial regeneration using rust-resistant seedlings, if available, would further advance the goals. Silviculture and/or fire can be used to generate the regeneration sites, as described in the former section.

Protecting & enhancing genetic diversity

The highly-selective mortality caused by white pine blister rust may reduce genetic diversity within the pine species; this effect is called a genetic bottleneck. Archiving seeds and pollen from population before the rust invades will preserve the diversity for future use in breeding programs or conservation projects into the future. 

Common Management Misconceptions

Misconception 1: "Management of high elevation forests does not seem like a good way to preserve them."

It is important to remember that many of the threats to these ecosystems are from human-induced change such as fire exclusion and non-native disease introduction. Some of the possible consequences of non-intervention are extinction and isolation of many high elevation forests, as well as loss of cultural, ecological, and hydrological benefits of these pines.

The aspiration to sustain these ecosystems in their natural form is important. However, the "hands-off" approach does not ensure the landscape sustainability over time, as has been seen in heavily-impacted areas. Restoration and proactive management attempt to preserve and provide regeneration opportunities for these pines for future generations.

Misconception 2: "These pines are so stress tolerant and have lived for centuries; they can persist through these threats."

It is true that high elevation white pines have evolved to be very tolerant of harsh conditions. However, the stresses they face today are new and not ones to which they have evolved tolerances or defenses. White pine blister rust is a new stress in North American forests; it was introduced in the early 1900s. As a result the white pines of North America have little defense to this novel stress. The slow growth, delayed reproduction, and low levels of natural rust resistance of these pine species provide a poor prognosis for the sustainability of these forests. Management intervention can help accelerate natural selection and the establishment of rust-resistant genotypes on the landscape.

Misconception 3: "Saving existing trees will save the species."

The cornerstone to sustaining the species for generations to come is increasing the frequency of heritable resistance on the landscape. To sustain the ecosystems, the entire regeneration process must be functional, including seed production, seed dispersal, seed germination, seedling establishment, seedling growth, and maturity. If an existing tree does not have genetic resistance, the seedling that develops from its seeds is not likely to have resistance and will therefore be susceptible to white pine blister rust and will not contribute to the next generation of trees. Without successful regeneration, the forest will not be able to recovery after a natural disturbance such as wildfire or windthrow. The existing trees provide the genetic diversity that provides the rust-resistant genes but management intervention may be needed to accelerate natural selection and the establishment of rust-resistant genotypes on the landscape.

Slow the Spread campaign

The USDA Forest Service in the Rocky Mountains has initiated a campaign called "Slow the Spread". This is an effort to widely educate people about the threat of white pine blister rust on Rocky Mountain bristlecone pine and limber pine forests. The recent discovery (2003) of white pine blister rust in the Sangre de Cristo mountain range in Colorado has been one of many motivating factors for this campaign.

They are urging people to not move, transplant, or buy trees that are infected with white pine blister rust. Through providing educational materials, they hope to help individuals learn to identify five-needle pines as well as the symptoms of blister rust. They are asking anyone who spots blister rust to report it to the Forest Service. At the same time the campaign is encouraging local Forest Service districts not to sell transplanting permits for white pines or Ribes.

As a part of this campaign the Forest Service is providing informational brochures at national forest information centers, hanging posters at prominent trailheads, and working with the National Park Service to assure the message is included among the park newsletters and entrance brochures.
 

Find out more about the Slow the Spread Campaign and what you can do to help:

• What you can do to Slow the Spread - Flyer
• What you can do to Slow the Spread - Poster

• Contact your local National Forest or Park to ask about their management of high elevation white pines. You may be able to volunteer to help their efforts.

   

For Teachers and Students: Getting real with scientific inquiry

Content Developed from:
Brustein, F.C. and Yamaguchi D.K. 1992. The Oldest Known Rocky Mountain Bristlecone Pines (Pinus aristata Engelm.) Arctic and Alpine Research. 24:3 253 - 256.

Scientists and students use the process of scientific inquiry to answer questions about the world we live in. They begin by asking a question and then use evidence to answer it. Most of what we have learned about the natural world has been discovered through using scientific inquiry.

Take a real journey with two scientists Dr. Brustein and Dr. Yamaguchi to learn more about what they discovered about Rocky Mountain bristlecone pine.

1. Formulate a Question

Up until the time of this investigation, the oldest known Rocky Mountain bristlecone pine was 1,500 years old. Dr. Brustein and Dr. Yamaguchi suspected and hypothesized that there were older trees and designed this investigation to prove it. 

The question they wanted to answer was: "What are the ages of the oldest living Rocky Mountain bristlecone pines?"

2. Design a Scientific Investigation

When designing this investigation, the scientists needed to figure out how to:

1. Select the oldest trees without already knowing their age,
2. Determine the age of the trees
3. Confirm the results are accurate

How did they select the oldest trees without already knowing their age?

The scientists looked at a combination of tree characteristics and site characteristics to figure out which trees may be the oldest.

What are the site characteristics where the oldest bristlecone pines grow?

Based on previous investigations, the scientists knew that the oldest Rocky Mountain bristlecone trees tend to grow in places that are dry and isolated. There are many clues to look for and tools to utilize when trying to find a dry site. The ones they used in this investigation were:

• Maps of regional precipitation and runoff
• Looking down at the ground to find areas that were well-drained on slopes that were very rocky
• Checked a compass to find south-facing slopes because south-facing aspects are warm, dry, and sunny

They also looked for sites that were isolated from natural disturbances such as fire. Bristlecone pines that are isolated tend to be located in small open groves separate from larger forested areas by rocky terrain. If the trees are separate from the rest of the forest, by rocks and boulders for example, the likelihood that a fire could reach them is low. Also, if there is a lot of space between the trees it is not likely that a fire could spread.

What are the tree characteristics of the oldest Rocky Mountain bristlecone pines?

The authors looked at each tree to determine if it had the characteristics of a very old bristlecone pine. Old bristlecone pines have strip bark growth, erosion-sculpted wood, crown dieback, and a radius exceeding 40 cm.

Bristlecone pines can live to such old ages because they have adapted many unique characteristics such as strip barking. As the tree ages, the

bark from most of the tree dies back leaving only a strip of functional bark. The strip of bark that is left is generally on the most protected side of the tree. The side of the tree that is no longer living becomes the erosion-sculpted wood. Essentially, this is what happens to the dead wood after withstanding the force of windblown ice and sand. It gradually wears away the exposed wood.

Another measure of the tree's age is crown dieback. This is determined by looking at the number of branches in the crown of the tree that are dead. The branches in the crown of the tree generally only die back when the trees is under stress or very old in age.

Determining the radius of the tree can be another indicator of old age. Older trees have more rings therefore tend to have a larger radius. Many other factors can influence the radius of the tree especially local site and climatic conditions, competition, water and nutrient availability, and the presence of insects of disease. Therefore, it is not always safe to assume because a tree has a large radius that it is old or vice versa.

3. Collect the Data

How did the scientists determine the age of the trees?

Dr. Brustein and Dr. Yamaguchi used a combination of tools and techniques for aging the trees to determine which Rocky Mountain bristlecone pines were the oldest.

What tools did they use?

At each of the selected sites, they collected increment cores from the oldest looking trees. A tool called an increment borer is used to collect an increment core. It is a hollow drill that takes out a slender core of the tree. The core, once extracted, contains tree rings that are used to determine the age of the tree. Generally speaking, taking a core from a tree does not do much harm to it. However, it can cause stress to the tree, therefore, you should have a good reason to core a tree and be sure to report your findings so that other do not have to repeat the damage later.

What techniques did they use?

At each site, the scientists took tree cores from both old trees and younger trees to aid in crossdating. Crossdating is a process of matching ring patterns between two trees. This helps to avoid errors in counting and verifies the accuracy of the rings that have been counted.

The cores were then dried, mounted, and sanded following a standard procedure that was developed by other scientists in previous tree age investigations. They counted each of the rings in the increment core with a microscope. In order to assure that they counted each year correctly, they crossdated their results with the cores from the younger trees from the same site.

What are tree rings and what do they tell us?

Each year, trees grow in diameter and produces new wood in a layer just beneath the bark called the cambium. Most trees produce a lighter color wood in the spring and a darker color wood later in the season. The alteration of light and dark wood is what makes the ring easily recognized and counted to determine the age of the tree.

The width of the ring reflects the growth rate of the tree in a particular year. The growth rate depends greatly on the amount of rain during the growing season. The width of a ring can be used to reconstruct rainfall patterns in the past. Understanding the climate in the past helps us to understand the current and predict future climate trends.

Why is crossdating important?

Occasionally, trees will produce more than one ring in a year. The extra ring is called a false ring, and it can be the result of drought stress in the middle of a growing season. Other times a tree can go a year without producing a ring. This can happen when the tree is suffering from severe stress like being burned in a fire, attacked by insects, or adverse weather conditions. When you crossdate, you use a tree that doesn't have a missing ring to find where other trees do have missing rings.

4. Analyze and Interpret the Data

After collecting the increment cores and counting the tree rings, the scientists needed a way to organize all the information. They chose to display it in a table. Using a table, they could keep track of all the information that they collected and calculated with mathematics on each tree.

When they calculated the final results, they were happy to find that their hypothesis was correct. There are Rocky Mountain bristlecone pines older than 1,500 year old - much older! They found 12 trees older than 1,600 years. They discovered that four trees were more than 2,100 years old and the new oldest known bristlecone pine was at least 2,435 years old!

5. Communicate the Process and Results

The scientists decided to share the results of their investigation in a paper that was published in a scientific journal. This is a very common way that scientists communicate to one another the process and results of their work. In the paper, they described each aspect of their investigation including:

• How they selected their study sites and trees
• The methods that they used to determine tree age
• The result of their investigation
• Discussion and explanation of the results

Bonus: Critical Thinking Questions

• What tools and techniques did the scientists use to gather the data?
• How did the scientist use mathematics in their investigation?
• How did the scientists' critical thinking skills help them to avoid making errors when counting the rings?

Other educational resources:

Nova Online - Features Methuselah Tree
Leonard Miller Site on Ancient Bristlecone Pine Forest

Many adventurous spirits have been lured by their curiosity to catch sight of the twisted and distinctive forms of high elevation white pines. These irreplaceable and unique ecosystems are highly valued by many. They are seen as symbols of patience, perseverance, and tolerance. The trees themselves are appreciated for their artistic forms and extreme longevity. find a source of aesthetic enjoyment and appreciate the habitat they provide for wildlife, watershed protection, and even a little shade on a sunny high mountain day.

These pines have been the motivation and focal point of varied artistic expressions. Many have conveyed their respect and awe through music, writing, art, photography and other types of media. Although it is difficult to quantify exactly and precisely how these tree are significant in our culture, it is undeniable that they are and countless have been moved by their experiences in their own unique way.

There are many references to these wondrous trees throughout our society. Here are just a few examples:

Music

"Way up in the mountains on a high timberline, there's a twisted old tree called the Bristlecone Pine. The wind there is bitter; it cuts like a knife. It keeps that tree holding on for dear life."

Excerpted lyrics from the Bristlecone Pine Song written by Hugh Prestwood.

"Sequoia and bristlecone pine,
They are ancestors!
The cactus and mushroom divine,
We are related!
The D.N.A. that runs through us all,
Is the key.~
We are one family!"

Excerpted lyrics from "We Are One Family" by Issac Bonewits. 

Poetry

Forest visitors

"As dawn breaks, my backlighted silhouette,
gnarled and twisted by forces that ebb and flow
across time and space, stands a silent watch.
My stark, misshapen, still rugged body
has adapted well to that over
which I have had no dominion.
Designated by design or default
as the chronicler of decades, centuries,
and millennia, I anchor time to space
on a subalpine bed of dolomite,
my wellspring of life.
With regards from an old Bristlecone Pine"

~ Excerpt of a poem by "To Whom It May Concern:" by Frances Johnson. 

Krummholz 

"Hunched like an anchorite behind its boulder, 

a treeline pine weathers the winter storms.

Its knotty branches shrink as nights turn colder.

Caught in its tufts, a fluted snowdrift forms.

When summer bares the mossy flanks of bosses

and lakes of lupine bloom on alpine meads,

the stunted pine regrows its winter losses,

cracking rocks to meet its meager needs.

Under its boughs the mantled squirrels nibble

on tender forage plucked from fields of sedge.

Below its roots the braids of snowmelt dribble

in purling pools from ledge to jointed ledge.

Off-trail two hikers hunker in its cranny

for shelter from the wind-bedeviled sky.

At dusk the twisted krummholz looks uncanny,

its limbs outstretched as though to prophesy.

Driving tent-stakes deep in prickly humus,

we pitch our camp and gather sticks to burn.

The resin-scented plumes of smoke perfume us

while overhead the Bear and Draco turn. °

As embers fade, our tangled limbs keep burning,

a blaze no dozing squirrels scent or see

though tufted ears might hear us turning, turning.

O!  Crooked love beneath the crooked tree.

~ Krummholtz Poem by Alan Sullivan

Books

"...the scarred and wounded bristlecone proclaimed a steadfast courage. These weather gales. They know how to handle the rough times. They survive. I could learn from them."  

"Only when they face the fiercest of the elements do they live unusually long lives."

~Quotes from A Strew of Wonder: The story of the Bristlecone pine at Windy Ridge, Colorado by Roberta Fiester published by the Summit Historical Society, 1993.

Other books:

• A garden of bristlecones - tale of change in the Great Basin by Michael Cohen; published by University of Nevada Press, 1998.
• Bibliography of written Bristlecone Pines resources
• Jane Braxton writes about her experience visiting bristlecone pines in California

Crafts and Hobbies

Rio Grande Woodworking makes bristlecone pine boxes
High elevation white pines used in Bonsai

Photography & Painting

Walking among the Bristlecone
Phillip Colla Natural History

Cline Photography

Painting of RM bristlecone pine by Terry Gardner

Photography by Scott Haefner - Ancient Bristlecone Pine Forest