Sunday, November 8, 2009

TORREY PINE – Pinus torreyana


Arborist Report - Pine Tree Inspection

Job site:
G residence
Laguna Beach, CA. 92651
On April 8, 2003, I inspected one Torrey pine (Pinus torreyana) located at the residence under construction. I was contacted by Kyle Hayden and informed that several tree roots were encountered while excavating for installation of a new concrete walk way.
The Torrey pine is a mature tree 50’ tall with a 42” DBH trunk located 8’ from the corner of house. Multiple roots had been exposed and some had been cut or split. The larger roots were in relatively good shape, with minimal wounding. The trees overall health at the time of inspection is good with the possibility of Pitch Canker affecting small portions of the tree. This tree is a Heritage tree registered with the City of Laguna Beach, Ca.
Site observations
The exposed roots were located 12” below existing finish grade approximately 4’ from trunk. The 5”-6” diameter root ran diagonally through the excavation for about 5’ with a 3” branch root that had been severed. Smaller roots were also exposed, 5 roots with diameters from 1” – 3” were damaged.
or cut. The soil is sandy loam with a neutral PH of 7.0. PH reading was obtained with a hand probe in the field.
photo 1. Exposed tree roots. Torrey pine at Catalina St. Laguna Beach.

Action taken
· All damaged roots with a diameter of 3” and smaller were pruned with a clean cut to minimize entry for pathogens.
· Cover exposed roots with native soil.
· Install bricks on a sand sub base over roots. Sand type to be washed masonry.
· Install plastic sheets under new concrete to minimize leeching from concrete.
Roots support the tree, store energy reserves, absorb water, and with the help of root-associated fungi, absorb elements that are essential for life. There are woody roots and nonwoody roots. The woody roots are large support roots and smaller fine roots, The nonwoody roots are nonmycorrhizal or mycorrhiza— associated with fungi.
The anatomy of roots is basically the same as trunks. The roots have a vascular cambium, bark and wood. There is no pith in the center of roots. The roots usual­ly have more parenchyma cells and fewer fibers. The distinction between growth rings is not as clear in roots as it is in trunks. Roots do not have a normal, colored, core of heartwood. The anatomical changes from trunk to root occur in a transition zone at the base of the tree. There is seldom an abrupt anatomical change from trunk to root. If there is a pith center, the section is trunk and not root.
Roots, like branches and twigs, also age and die. As roots die, boundaries form that resist the inward spread of pathogens. When nonwoody roots die, a corky periderm —boundary — forms that separates the nonwoody infected root from the healthy woody root.

Heritage Trees

Landscape and Scenic Highways Resource Document - City of Laguna Beach

May 23, 1995

Torrey Pine
RES. NO. 75.200

Topic 4 - Heritage Trees

Trees are an important resource in Laguna Beach for a variety of reasons. Trees of all kinds, shapes and sizes contribute to the scenic beauty of the City. They protect the soil from erosion, provide cooling shade and help to cleanse the air of pollutants. Preservation of trees is very important to preserving and protecting the beauty and character of Laguna Beach. Trees also represent an aspect of Laguna’s heritage--some of the oldest trees (oaks and sycamores) may pre­date homesteading and the formation of the City. Other groups of trees (the Blue Gum and other Eucalyptus groves) date from the end of the 19th century. Throughout town, there are many trees that are large and prominent, rare or unusual.
In 1975, the City Council adopted an ordinance establishing criteria and procedures to recognize and protect heritage trees, (trees of large size, historical significance or unique appearance). The heritage tree regulations may be found in Title 12 of the Municipal Code. Protection of heritage trees is accomplished through a permit process which reviews proposals for major pruning, substantial alterations, removal or construction within close proximity to heritage trees. Exceptions are made for trees that are hazardous or dangerous to life and property. The designation process, as specified in the Municipal Code, requires nominated trees to be officially placed on the Heritage Tree List by the City Council through a public hearing process.
A list of the current heritage trees appears in Appendix C. As part of the neighborhood surveys, the landscape task force prepared a list of trees which would qualify to be designated as heritage trees. This list of “Candidate Heritage Trees” is also in Appendix C. An inventory of candidate heritage trees was prepared for the South Laguna area in 1983, before it was annexed into the City. This list was later adopted by City Council resolution when the South Laguna Specific Plan was consolidated into the Laguna Beach General Plan. These trees do not enjoy the same protection as those that were designated heritage trees under the City’s ordinance. Therefore, these trees also appear on the candidate heritage tree list along with the list of candidates for the rest of the City.
The candidate heritage tree inventory is intended to bring public attention to the role that the community’s landscape plays within developed areas by spotlighting the most outstanding specimen trees. The number of trees on the heritage tree candidate list is an indication of the wealth of plant material which enriches our environment. Title 12 of the Municipal Code states that a heritage tree should meet at least one of the following criteria:
· be of historical significance or appeal;
· have a single trunk with a circumference of 55 inches or more, or a multiple trunk of 100 inches or more in circumference (measured at 24 inches above grade); or
· have unique characteristics of form or shape.
Issue Statement and Policies
Landscape and Scenic Highways Resource Document - City of Laguna Beach

In preparing the heritage tree candidate inventory, the task force used the following clarifications/additions to the criteria:
• known to be of pre-1940 age;
• large size of specimen compared with commonly seen sizes of that particular species;
• associated with a person or an event of community wide significance;
• large size remnants of the original native vegetation; or
• scenically prominent.
In addition to the above, the trees were visible from streets or other public areas. In order to clearly communicate the intent of the heritage tree ordinance it may be necessary to reevaluate the wording of the ordinance and supplement the existing heritage tree criteria.
Decisions as to which trees to include on the list were sometimes difficult, since the individual characteristics of trees vary, as does the degree to which trees meet the heritage tree criteria. Undoubtedly, some of the trees are not as worthy as others, and certainly there are eligible trees which were missed in preparing the list. However, the intent of developing the heritage tree candidate list was to document outstanding trees that represent important resources. The candidate list sets a general standard against which other trees that may be proposed for heritage designation may be evaluated. It was felt that having the candidate list would give recognition to worthy trees and minimize the possibility that trees of less than heritage quality would be proposed as heritage trees. The inventory is also helpful because future development can be designed to accommodate a candidate tree rather than cause its removal. However, a candidate tree would have to be officially designated as a heritage tree in order for the protections of the ordinance to be applied. In order to encourage property owners to preserve heritage trees, consideration should also be given to offering incentives for designation and preservation of heritage trees on private property.
Many of the heritage tree candidates are within City right-of-ways. The City can set an example for heritage tree preservation and officially designate these trees as heritage trees; only some of these are currently being maintained by the City. It seems appropriate that when consideration is given to allocation of limited funding for maintenance, priority be given to heritage and candidate heritage trees.

4A. Foster community appreciation for the heritage tree program.
4B. Encourage the registration of qualified trees as heritage trees by developing an incentive program, such as fee waivers, similar to the one established for preservation of historic structures.

4C. Promote maintenance practices for heritage trees that will result in optimal shape and character for the tree based on its species.
4D. Consider registering City-owned trees on an individual basis which are on the Candidate Heritage List as heritage trees and promote proper maintenance of such trees.
4E. Consider developing a plan for the inspection and maintenance of heritage trees that are located on City property, within the public right-of-way.
4F. Consider modifying the heritage tree ordinance to allow applicability to all species and to increase the required property owner notification radius.
4G. Encourage the preservation of existing trees where feasible in conjunction with development approvals.
Tree Summary and History
Botanical name: Pinus torreyana
  Common name: Torrey pine
  Family: Pinaceae (Pine)
  Habitat: Dry slopes below 500' near Del Mar on San Diego Co. coast,
  coastal scrub, chaparral, Santa Rosa Island, RARE
Species summary:
Torrey pine is one of the rarest trees in North America, and the rarest pine in the United States. It is restricted to a small region of coastal California just north of San Diego, and to a single stand on Santa Rosa Island off the California coast. Torrey pine is threatened by development, which has already eliminated all but a few protected stands, and by several serious insects and diseases. The most serious of these, pitch canker, threatens the species with extinction. Torrey pine is one of only a few hard pines (section Diploxylon) with 5 needles.
Meanings of names:
Genus name:  Latin name for Pine
Species name:  for John Torrey, botanist.
Common name:  John Torrey, botanist. Pine is from Old English, related to Latin Pinus, Greek Pitys.
Common name:  Soledad pine, Del Mar pine
Species Distribution
Range map:
Map picture
Natural History Narrative:
Ecology:  Torrey pine is a rare endemic occupying a narrow strip along the coast of southern California on bluffs overlooking the Pacific Ocean near the town of Del Mar. Soils are deep sands, highly eroded on the bluffs overlooking the ocean. Torrey pine occurs within the California coastal chaparral forest and scrub ecoregion (Mediterranean hardleaved evergreen forest), meaning that nearly all rainfall is in the winter, and the soils is quite dry throughout the summer. Fog is common throughout the year, and fog drip is probably an important source of moisture. Torrey pine occurs in pure stands with only about 3,000 mature trees in the entire mainland population. 
A second population occurs in a single stand on Santa Rosa Island off the coast of California. The habitat is similar to the mainland stand, a sandy, dry, eroded hillslope in the fog belt. There are only about 2,000 trees in this population.
Although both the Torrey Pines State Park and Santa Rosa Island populations are protected from further development, they are threatened by insects and diseases (see Interactions, below). The mainland population has been substantially reduced in recent years by insects and disease, and the continued existence of these population is in doubt, despite the best efforts to protect it. 
Life History:  Torrey pine reproduces from seed. Wind pollination takes place in January-February, during the wet season. Cones mature in three years (a year longer than in most pines) and some of the heavy winged seeds are released in fall. Cones are persistent, remaining on the tree for many years after maturity, and some seeds continue to be released over several to many years. 
Although the seeds are winged, like those of other pines, they are too heavy to float on the wind, and usually drop straight down. Seeds are consumed from the cones and off the ground by birds and small mammals, particularly by scrub jays, Aphelocoma coerulescens. These birds fill their crops with seeds, and may fly long distances carrying seeds. Scrub jays are undoubtedly the major agents of dispersal, particularly over long distances.
Growth of the shoot is very slow, but root growth is more rapid, and trees typically have a high root/shoot ratio. At maturity, Torrey pines typically have a broad, crooked crown and reach only about 30 ft. in height. This is due to the harsh climate in which they live: cultivated trees in milder climates are tall with narrow crowns, a form more typical of pines.
Interactions:  Torrey pine is wind pollinated. Seeds are dispersed by gravity and birds, primarily by the scrub jay. Torrey pine stands are infected with a disease, pitch canker, caused by the fungus Fusarium subglutinans f. sp. pini. The fungus is native to the southeastern US and was introduced to California. Pitch canker has the potential to reduce genetic diversity and threaten the stability of the Torrey Pine stands.
Modern uses:  All remaining native Torrey pines are protected. The species has been grown in New Zealand and Australia for testing as a potential timber tree. However, the wood is brash, and limited seed availability and genetic variation make this species less desired in the southern hemisphere than is Monterey pine, Pinus radiata
Traditional uses:  Native Californians burned Torrey pine stands to regenerate them, and may have planted seeds. The seeds were locally important for food, particularly for the Kumenay people.
Ornamental Considerations:
Ornamental uses:  Little used, but deserve wider planting within the California coastal chaparral. Ornamental plantings within the original range of the species are fairly common, but continued use of the species is problematic because of the risk of spreading pitch canker.         TreeGuide Inc.
Pitch Canker Disease
1. What is Pitch Canker?
Pitch Canker is a disease, which causes die-back of individual branches (figure 1), leading to a general decline in tree health, and, in some cases, premature death. This disease mainly affects pine trees in central coastal areas of California, but it has been found north of San Francisco in Mendocino County and as far south as San Diego County.

TO LEFT: Fig 1. Multiple branch tip infections in Monterey pines grown on a golf course.

2. What Does Pitch Canker Look Like?
The earliest symptoms of pitch canker are usually dead branch tips in the upper part of the tree canopy. Needles on the ends of these branches are either wilted (figure 2), red, dead or absent, and resin exudation is associated with the point of infection on the branch (figure 3). A more advanced symptom of the disease is the appearance of resinous cankers on the main stem and larger branches of the tree (figure 4). After the appearance of these stem cankers, the top of the tree may be killed by beetles, and death of the tree may result.

ABOVE: Fig 2. Infected Monterey pine shoot. Discolored area of shoot is the lesion resulting from infection by the pathogen. Note the wilting of the tip of this shoot.

ABOVE: Fig 3. Resin exudation from infected Monterey pine branch tip. Needles distal to the point of infection wilt and die.


TO LEFT: Fig 4. Cankers on the main stem result in copious resin exudation.

3. Where is Pitch Canker Found?
In the United States, prior to 1986, pitch canker was only known from the southeastern states. The disease was first recognized in California in 1986. It has also been found in various parts of the world, including Mexico, Japan and South Africa. Within California, pitch canker is limited to coastal areas, mostly from San Diego to Mendocino counties. To date there are no confirmed records of pitch canker from the Sierra Nevada or other locations east of the central valley, or farther north than Mendocino County.
4. What Trees are Affected by Pitch Canker in California?
Pitch canker affects many native pines in California, including Monterey pine, Bishop pine, knobcone pine, gray (foothill) pine, coulter pine, Torrey pine, ponderosa pine, and shore pine. Douglas-fir, another native California conifer, is also susceptible, although less so than most pines. For ponderosa and Torrey pines, and Douglas-fir, naturally infected trees have been observed only in planted stands, and not in native forests.
5. Are All Susceptible Tree Species Affected To The Same Extent?
No. Of the native pines, Monterey and Bishop pine are the most widely affected. Knobcone pine and shore pine are also severely affected in some areas. Other native species are known to be susceptible, based on greenhouse tests, but are not common in the areas where pitch canker is found, and consequently infected trees are rarely seen. Among non-native pine species commonly found in landscape settings in California, Canary Island and Italian stone pines are relatively resistant to pitch canker. Allepo pine is intermediate in susceptibility.
6. What Causes Pitch Canker?
Pitch canker is caused by a fungus called Fusarium circinatum. Old names for this fungus include Fusarium subglutinans f. sp. pini, and Fusarium moniliforme var. subglutinans. Many other Fusarium species are commonly found in soil, some of which cause wilt diseases. Among the crops affected by Fusarium wilt disease are melons, cotton and tomatoes.
7. How Does Pitch Canker Spread?
The pathogen produces airborne spores that can be spread by wind, and carried by native insects.
Insects known to carry the pathogen include bark beetles and twig beetles, which feed under the bark of large and small diameter tree material respectively, and cone beetles, which attack cones on the host tree. Many of these insects are known to transmit the pitch canker fungus to healthy trees and are considered to be the primary means by which new infections are established. Although beetles can spread the disease to new areas, long distance spread is more likely to result from people transporting logs, nursery stock, seeds or soil, in which the pathogen is known to survive for long periods of time.
8. Are There Trees That Do Not Get Pitch Canker?
Yes. It has been shown that some Monterey pine trees are resistant to pitch canker. In addition, some trees in long term survey areas have only exhibited a very limited amount of damage caused by the fungus. These trees are not expected to die from the disease unless new strains of the fungus are introduced into the state and are able to overcome the natural levels of resistance which already exist.
9. Is There a Cure For Pitch Canker?
Because the fungus is inside the host tree, host trees are often large, and many insects are involved in the dissemination of the fungus, there are no practical direct methods of control of pitch canker. However, actions can be taken to slow the spread of the disease. These techniques reduce the number of insects emerging from plant material and carrying the pitch canker pathogen. These include debarking recently killed trees and branches, and timely chipping and removal of diseased or insect infested tree material from nearby susceptible trees.
10. Will Pruning Infected Branches Slow The Decline of The Tree?
In most areas where pitch canker occurs, infected branch tips are so numerous that it is not practical to remove them all. Even where this is possible, repeated pruning will be necessary, as new infections are likely to occur. In cases where the incidence of pitch canker is isolated, the timely removal of diseased branch tips may be effective in slowing the spread of the disease. It should be noted however that the benefits of this practice have not been demonstrated in full scale field studies.
11. Can I Prevent Pitch Canker From Getting Into My Trees?
There is currently no proven method for preventing pitch canker from infecting trees in areas where the fungus is established.
12. What Do I Do If I Think a Tree Has Pitch Canker?
If other trees in the area have pitch canker, there is little that can be done for individual trees. However, tree removal should only be considered if a tree becomes hazardous or unacceptably unsightly. Confirmation of the disease in trees requires isolation of the fungus, and details about this information can be obtained from your county agriculture commissioner’s office, or U.C. Cooperative Extension.
13. How Far Will Pitch Canker Spread?
Given the geographic range of susceptible host tree species, the potential for spread is great, and includes the northern coast of California and the Sierra Nevada. Work is underway to determine if climatic conditions, differences in host susceptibility or insect vectoring potential will limit disease spread.
14. What Can I Do To Help?
The biggest concern about pitch canker at the current time is the potential for the disease to spread into the forests of the Sierra Nevada. To help reduce the risk of this occurring, no Monterey pine or other pine material should be transported from West of Interstate 5 to East of Interstate 5. Any firewood, cones, logs, and chipped pine material should be utilized in the local area where it originated. These types of material may carry the fungus, its insect vectors, or both, and increase the risk of spread of the disease if transported outside of the local area.
15. Where Can I Get More Information About Pitch Canker?
A variety of information sources are available including printed documents, and information on the internet. Documents and links relating to pitch canker can be found at:
In addition, there is a growing source of information about the disease in the scientific literature. Some recent publications are listed below:
Gordon, Thomas R., Dorothy Okamoto, Andrew J. Storer, and David L. Wood. 1998. Susceptibility of five landscape pines to pitch canker disease, caused by Fusarium subglutinans f. sp. pini. Hortscience 33: 868-871.
Gordon, Thomas R., Karen R. Wikler, Andrew J. Storer, and David L. Wood. 1997. Pitch canker and its potential impacts on Monterey pine forests in California. Fremontia 25(2): 5-9.
Storer, Andrew J., Paul L. Dallara, David L. Wood and Thomas R. Gordon. 1995. Pitch Canker Disease of Pines. Calif. Dept. Forestry and Fire Protection, California Forestry Note. #220, 18p.
Storer, Andrew J., Thomas R. Gordon, David L. Wood and Pierluigi Bonello. 1997. Current and future impacts of pitch canker disease of pines. Journal of Forestry 10(12): 21-26.

Information provided by University of California Cooperative Extension
Last updated August 2000         
Summary / Conclusion
Thank you for calling on my services with your questions regarding your Torrey pine tree roots. Do not cut off the large roots, as this could adversely affect the health of the tree. The damage to the roots was minimal and I was able to prune the damaged roots to minimize any future problems with root decay. The installation of brick paving on a sand sub base over the roots is an acceptable solution for your walkway. For any future construction activity in proximity to your trees, be aware that you will encounter more roots, as this species of tree has a extensive root system when mature. If small roots are cut or damaged be sure to cut the root cleanly with sharp bypass pruners.
Although there is no cure for pitch canker, with proper care, your tree should be able to compartmentalize the disease and remain healthy.
If you have any questions concerning this report or if I can be of further service to you, please call me at any time.
Craig de Pfyffer
Certified Arborist
Certificate # WE-6533A
Expiration Date: 12-31-2005
Although all the recommendations in this report are based on sound and accepted horticultural practices, the author cannot be held responsible for the final outcome of the recommendations, or any liabilities associated with this project. Tree inspections, in this case, do not cover internal cavities, structural defects, or diseases with non visible symptoms.
P.O. Box 247, Laguna Beach, CA. 92652 ·
Tel: (800) 811-3010 Fax: (800) 811-3014

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