FOREST HEALTH CONSIDERATIONS FOLLOWING HURRICANE RITA

by H. A. (Joe) Pase III

Texas Forest Service Lufkin, Texas

On September 23-24, Hurricane Rita made landfall along the Texas-Louisiana coast as a Category 3 storm. It moved north through East Texas and was still a Category 1 storm when it passed through the eastern part of Angelina County, some 125 miles inland. Sustained winds and gusts in excess of hurricane force damaged much timber in East Texas -- some 771,000 acres were damaged or affected with anticipated losses of $833 million. The damage to forestlands, watersheds, and wildlife habitat from Hurricane Rita is extensive and will be felt for years to come. The figure below shows Hurricane Rita storm damage categories in East Texas. The photograph shows an example of timber damage from Rita.

From time to time nature can be very unkind to our forests. Wind, hail, ice, insects, diseases, fire, and other natural agents can cause devastating losses. Uprooted and broken trees can cause loss of life, damage property, and disrupt electrical and phone service. Homeowners often ask what can be done to save damaged shade and ornamental trees and forest landowners are interested in how to assess the damage to their timber and minimize losses. In addition to the direct damage caused by the storm, insects and fungi often cause additional losses.

INSECT PROBLEMS THAT REQUIRE IMMEDIATE ATTENTION Recently-cut trees and logs, trees damaged by storms or other causes, and dying trees are very susceptible to insect attack. Following Hurricane Rita, storm-damaged timber should be salvaged as quickly as possible to prevent serious degrade from insects. The most damaging insects that initially attack downed pine trees and logs are ambrosia beetles and wood borers. AMBROSIA BEETLES Ambrosia beetles are an interesting group of insects. They do not feed on the wood of their host trees, but rather feed on a fungus (called “ambrosia”) they inoculate on the walls of the tunnels they chew in the wood. Ambrosia beetles will attack trees and logs of pine and hardwood and can cause serious degrade of lumber and plywood products. The galleries (about the diameter of the lead of a wood pencil) not only make a physical hole in the sapwood and heartwood, but the “ambrosia” fungus will cause a black stain on the wood around the gallery. In the South, the ambrosia beetle known as Platypus flavicornis can infest dead and dying pine trees, stumps, logs, and unseasoned pine lumber, especially during the warm months of the year. Wood that has a moisture content below 48% is seldom attacked by these beetles. They may also attack, but not kill, living trees in areas where the cambium and bark have been damaged. The adult ambrosia beetles typically colonize the lower 6-8 feet of the trunk of the tree. The beetles land on the bark and then bore through the bark and into the sapwood and heartwood of the tree. As they construct their galleries, they expel (sometimes in large quantities) creamy-white, fluffy “sawdust.” This sawdust that collects around the base of the tree is very characteristic of their attacks (see photos). The beetles (see photo) are small (about 5 mm long), slender, elongate and have two prominent spines at the rear of their wing covers (elytra). These two spines have earned this insect the nickname “Cadillac beetle” because the spines resemble the tail fins on Cadillac cars from the 1960s! ROUNDHEADED WOOD BORERS (SAWYERS) Wood borers (called sawyers) will also infest dead and dying pine trees and logs. They require the presence of bark on recently cut or dead trees to initiate an infestation. Eggs are laid on the bark and the larvae or grubs begin feeding between the bark and the wood. After a month or so, the larvae cause damage by boring into the wood to complete their life cycle. Tunnels in the wood may be over one-quarter inch in diameter. REDUCING DAMAGE Damage caused by ambrosia beetles and wood borers can be reduced by prompt utilization or by keeping decked logs under a water sprinkling system. Rapid drying of green lumber is also encouraged. Use of insecticides is generally not recommended. Infested wood that is used for oriented strand board (OSB) is not impacted by these insects. A detailed report about insects and fungi that infest logs stored under a water sprinkler system following Hurricane Hugo in 1989 can be found at the following internet site: http://www.alaforestry.org/ivan/Publications/water_storage.pdf

How to recognize ambrosia beetles in storm-damaged timber.

PINE BARK BEETLES AND STORM-DAMAGED TIMBER Not only are ambrosia beetles and wood borers a concern, but forest landowners often expect a build-up of pine bark beetle populations, in particular the dreaded southern pine beetle, after timber is damaged by storms. In East Texas and across the South, storm damage to timber has not caused southern pine beetle outbreaks. The following discussion deals with bark beetles and storm-damaged timber. A brief comment about pine bark beetles needs to be made. There are five different pine bark beetles that attack and kill pine trees in East Texas (as their name implies, they do NOT attack hardwood trees). The southern pine beetle (SPB) is the most serious because it alone is capable of killing healthy trees and can kill large areas of pine timber (one uncontrolled infestation of SPB in Sabine County killed over 7,500 acres of pine timber in a 12-month period in 1993). The other four pine bark beetles (three species of engraver or Ips beetles and the black turpentine beetle) attack weakened, injured, and stressed pines and individual infestations seldom encompass more than 10-20 trees. They usually attack scattered single trees or two or three trees in a group. Salvaging beetle-infested trees, especially after a storm, is the recommended way to minimize losses caused by pine bark beetles.

PINE BARK BEETLES AND TORNADO-DAMAGED TIMBER IN EAST TEXAS Texas Forest Service Pest Management personnel monitored tree survival and bark beetle activity following a tornado that damaged pine timber in Montgomery and Liberty counties in May of 1983. On-site visits were made 10 weeks, 15 weeks, and 40 weeks after the storm. The following damage categories were used: Broken bole with no limbs Broken bole with 1-3 limbs Broken bole with more than 3 limbs Broken bole with crown still attached Uprooted Other (bent, leaning, scarred, etc.) SOUTHERN PINE BEETLE NOT AN ISSUE IN TIMBER FOLLOWING STORM DAMAGE As far as bark beetle attacks were concerned, no SPB were found in the storm-damaged timber in 1983. However, depending on the amount of damage to the tree, one or more species of engraver beetles and/or the black turpentine beetle attacked the trees. The lack of SPB and the presence of the other pine bark beetles in storm-damage timber occurred after a severe wind storm in East Texas in February 1998. This pattern has been reported in other areas of the South following storm damage. TEN WEEKS POST-STORM Ten weeks after the 1983 storm, all uprooted trees were attacked by engraver and/or turpentine beetles. Most (84%) of the trees with a broken bole and no limbs were attacked. Trees with a broken bole and one or more live limbs were largely uninfested at the 10-week check. FIFTEEN WEEKS POST-STORM Fifteen weeks after the storm, more damaged (weakened) pine trees had come under engraver beetle attack. Now many of the trees with broken boles that had one to three limbs were attacked as well as those that were bent, leaning, or scarred. 40 WEEKS POST-STORM After 40 weeks, most of the severely damaged trees had succumbed to bark beetle attacks. However, 63% of the trees with more than three limbs remaining were still unattacked. Also, only 8% of the trees that had a crown attached to the broken bole survived. Interestingly, very few undamaged trees were attacked by bark beetles indicating that healthy trees are of no interest to engraver or turpentine beetles, even in areas where populations of these bark beetles have increased. REDUCING TIMBER LOSSES FOLLOWING STORMS Forest landowners with storm-damaged timber should consider salvage logging as a way to utilize the timber rather than letting it go to waste. Timber salvage operations are more time

consuming than regular logging, therefore the prices paid for the damaged timber will be lower than standing, green timber prices. Salvage should be conducted as soon after the damage as possible before various wood boring insects and decay and stain fungi further degrade the timber. Also, dead timber often dries out rapidly and has less dollar value if weight scaled. Large volumes of harvested pine logs that will not be immediately processed at a mill can be kept under a water sprinkler system or in a log pond to prevent invasion of insects and fungi. BLUE STAIN FUNGUS When pine bark beetles attack pine trees, they introduce a fungus commonly called blue stain. This fungus grows into the sapwood and stains it a blue-gray color. It does not alter the strength quality of the wood. Wood products such as “2-by-4” studs and oriented strand board (OSB) would not be impacted by this fungus. It could have some impact on certain paper products. Dead timber left in the woods or on log decks for longer than two or three months are likely to be colonized by various decay fungi. These fungi can rapidly degrade the wood and render it unusable. Prompt utilization or storage under a water spray should keep decay fungi at bay. HIDDEN DAMAGE AND EXAMPLES FROM FLORIDA Following a storm, some pine trees my not exhibit any signs of damage other than leaning. These trees are commonly referred to as root sprung. Unless they are attacked by pine bark beetles, they may not die immediately, but they usually decline over a period of several years and eventually are attacked by bark beetles. Root sprung trees should be removed if a salvage operation is conducted. It is suspected that root sprung pine trees have likely suffered significant damage to the fine root structure because of the wind. The fine roots are responsible for the uptake of most of the water and nutrients from the soil. When this part of the root system is damaged, the trees enter into a stress situation. Dr. John Foltz, forest entomologist at the University of Florida for some 25 years, has had experience with hurricane-damaged timber in his state. He recently sent me the following comments about pine timber in Florida following hurricanes that occurred in 2004. I thought this was interesting. Dr. Foltz writes, “Here is a quick summary of what I have observed regarding insects and pine trees in the year since Charley, Frances, and Jeanne crossed over the Florida peninsula. Immediately following the storms there were many snapped and uprooted trees in the areas where the winds were strongest. Ips (pine engraver beetles) and all the other scavengers colonized [I refuse to say infested] the broken off material soon afterwards, but only slowly got into the rooted material where resin flow remained strong. During the winter many trees that "survived" the storm died and were colonized by insects. In early March I went to the Fort Myers area (Charley landfall) in response to an individual agitating for an SPB-type beetle suppression program. My assessment was that stem shake caused by high winds disrupted translocation and trees were then being colonized by Ips. There was no sign of any bark beetle outbreak. In August I did an assessment of the "pine decline" in the Palm Beach area where Frances came ashore. Scattered trees were fading rapidly, then being colonized by Ips and ambrosia beetles. The cause of death appeared to be unseen wind-caused internal injuries that disrupted translocation. The roots and trunk were unable to supply the water needed by the foliage even though there was adequate soil moisture. The mortality was scattered throughout clumps of trees -- my guess is that there was wide variation in the ability of individual trees to withstand the bending and twisting they suffered during the storms. In effect, these trees had been mortality wounded in September 2004, but did not die from these internal injuries until August 2005. I can't imagine any tree care program that could have substantially prevented or delayed this mortality.”

In addition, Dr. Foltz shared a recent (September 2005) correspondence he had with a Florida homeowner concerning pine trees and pine bark beetles. Again, I think his comments address some of the problems that are likely to occur within the next 12 months. Dr. Foltz writes, “Mr. Brown: The situation of engraver beetles in dead pine trees you describe for Martin County is probably the same as what I observed in nearby Jupiter and West Palm Beach 2 weeks ago. The situation there was that pine needles on scattered trees would rapidly progress from their normal green to a chlorotic green, red, and then brown color. An assessment of the bark and ambrosia beetles present in the dead trees indicated that the insects arrived to colonize the trees about the time the needles were turning red. This "late" arrival in conjunction with few or very small pitch tubes indicated the tree trunks were very dry and not delivering water to the needles in the crown although soil moisture has been more than adequate in recent months. The death of these pines was likely due to hidden trauma produced by the winds of hurricanes Frances and Jeanne. I believe the prolonged strong winds of theses storms ruptured a number of feeder roots without breaking the larger support roots. The winds may also have damaged the sapwood so that it was unable to supply the water and nutrients needed in the crown. Accepting that wind trauma is the real cause of death, we are still faced with two general questions: What can we do to help surrounding live trees? What should we do with the dead trees? To answer the latter question first -- The insects present in these trees are performing their normal ecological functions as scavengers of dead trees. This is NOT a situation where the insects are killing the trees. There is no need to do any insect management, either by killing beetles already in dead trees or by spraying living trees with an insecticide to prevent beetle attacks. In forested areas we would normally leave the dead trees to fall and decay. In most urban settings, however, the dead trees pose sufficient threat to people and property that they should be cut down. Tree removal generally becomes more hazardous and costly as wood borers and decay organisms degrade the wood, so get the work done as soon as possible. Stumps may be left at whatever height the landowner wishes. There is no biological reason for stump grinding. As indicated above, applying insecticides to severely traumatized trees will do nothing to prevent their death. For moderately traumatized trees, we might be able to extend their lives by promoting conditions that enhance the regrowth of the root system. Do what you can to improve the physical, chemical, and biological properties of the soil. Pruning a few live branches from the crown would reduce slightly the demand for water and nutrients and perhaps keep a tree from dying (I'm speculating here). We have no easy methods to assess the trauma of individual trees and no proven methods for mitigating such trauma. Perhaps the best way to view this situation is to consider it as an opportunity to redo the landscaping on your property. I hope the foregoing will help you assess and understand the insect-tree relations in your neighborhood. Best wishes. John L. Foltz, Forest Entomologist University of Florida” STORM DAMAGE TO HARDWOOD TREES We have been discussing damage to pine trees. What about hardwood trees? Fortunately, many hardwood trees will survive storm breakage. Hardwood trees that are standing and have even a small portion of the crown remaining will probably recover in time. However, the process may take several years. Large hardwood trees that are uprooted should be removed. It is important to remember that hardwood trees with large damaged areas on the trunk or large broken limbs may be infected with decay fungi. After several years, these decay fungi typically weaken a tree

structurally and make the tree more susceptible to storm breakage. Decay fungi probably won't kill a hardwood tree. Damaged hardwood trees in residential areas that are not removed should be properly pruned to eliminate broken branches and branch stubs and promote rapid healing. Following is a guide from the Texas Forest Service web site for homeowners to consider when evaluating damaged hardwood trees. (http://txforestservice.tamu.edu/shared/article.asp?documentid=1150) In the aftermath of Hurricane Rita, do not be hasty about removing damaged trees that might be saved. Trees are resilient, and what may look like mortal wounds at first glance are not necessarily fatal to a tree.

Safety should be the first concern. Take caution when pruning, and leave the heavy chainsaw work to professionals. Look up for damaged limbs that may fall, and look down to avoid fallen power, phone or cable lines.

Moderate and major tree damage, and any damage around power lines, should be left to professional arborists. They have the equipment and knowledge needed and are usually listed in the telephone book under “Tree Service.” You may also want to check with your city or county officials to see if they are providing assistance with disposal of tree debris from private property.

If the offered services include tree topping, beware. Tree topping is one of the worst treatments for trees because it reduces the amount of foliage, which trees need for food and nourishment during regrowth.

Be cautious of arborists soliciting door to door. A qualified tree-care specialist should have workers’ compensation, liability insurance, and experience in the tree care industry. Homeowners using someone without insurance could be liable for accidents occurring on their property. If possible, it is best to hire only an arborist certified by the International Society of Arboriculture.

Homeowners need to be careful with damaged trees if removal is necessary. Trunks and branches are heavy and should be considered potentially dangerous until they can be brought to the ground. Limbs as small as two inches in diameter can cause injury if they fall on someone.

Additional helpful information follows about urban tree evaluation following storms.

Can These Trees Be Saved?

Storms can leave trees looking like there’s no tomorrow. Major limbs have been broken or damaged, foliage has been shredded or stripped, or the bark has been torn or gouged. But what at first glance may look like mortal wounds are not necessarily fatal to a tree. Trees have an amazing ability to recover from storm damage.

The first step is to assess the damage. Before writing off a damaged tree as a goner, homeowners should evaluate their trees by asking the following questions:

Q. Other than the storm damage, is the tree basically healthy and vigorous?

• If the tree is basically healthy, is not creating a hazard, and did not suffer major structural damage, it will generally recover if first aid measures are applied immediately after the storm.

Q. Are major limbs broken?

• The larger a broken limb is, the harder it will be for the tree to recover from the damage. If a majority of the main branches are gone, the tree may have little chance of surviving.

Q. Has the leader (the main upward-trending branch on most trees) been lost?

• In species where a leader is important to upward growth or desirable appearance, it may have to be a judgment call. The tree may live without its leader, but at best would be a stunted or deformed version of the original.

Q. Is at least 50 percent of the tree’s crown (branches and leaves) still intact?

• This is a good rule of thumb on tree survivability. A tree with less than half of its branches remaining may not be able to produce enough foliage to nourish the tree through another season.

Q. How big are the wounds where branches have been broken or bark has been damaged?

• The larger the wound is in relation to the size of the limb, the less likely it is to heal, leaving the tree vulnerable to disease and pests. A two- to three-inch wound on a 12-inch diameter limb will seal over with new bark within a couple of years.

Q. Are there remaining branches that can form a new branch structure?

• The remaining limbs will grow more vigorously as the tree tries to replace its missing foliage. Look to see if branches are in place that can eventually fill out the tree’s appearance.

Q. Is the tree of a desirable species for its location?

• If the tree is in the wrong location (such as a potentially tall tree beneath a power line), or an undesirable species for the property (messy fruit, etc.), it may be best to remove it if it has serious damage.

The questions listed above will help you make informed decisions about your trees. In general, the answer as to what to do about a particular tree will fall into one of three categories:

1. It’s a Keeper

If damage is relatively slight, prune any broken branches, repair torn bark or rough edges around wounds, and let the tree begin the process of wound repair.

An Easy Call:

A mature shade tree can usually survive the loss of one major limb. The broken branch should be pruned back to the trunk. In the months to follow, large wounds should be closely monitored for signs of decay.

Minor Damage: Although the tree has been damaged, enough strong limbs may remain on a basically healthy tree to make saving it possible.

Too Young to Die: Young trees can sustain quite a bit of damage and still recover quickly. If the leader is intact and the structure for future branching remains, remove the broken branches and let the tree close over the wounds and recover itself.

2. Wait and See

If a valuable tree appears to be a borderline case, resist the temptation to simply cut the tree down and be done with it. In such cases, it may be best to stand back for a while and think it over. Remember that time is on your side. After careful pruning of broken branches, give the tree some time to recover. A final decision can be made later.

Easy Does It: Resist the temptation to prune too heavily. Remember that the tree will need all the foliage it can produce in order to make it through the next growing season. Remove only the damaged limbs; wait and see what happens.

Hold Off: A healthy mature tree can recover even when several major limbs are damaged. With large trees, a professional arborist should be brought in to assess damage on a borderline situation, and to safely accomplish needed pruning and branch removal.

3. Say Goodbye

Some trees simply cannot be saved or are not worth saving. If the tree has already been weakened by disease, if the trunk is split, or more than 50 percent of the crown is gone, the tree has lost its survival edge.

Tree Tragedy: This otherwise healthy young tree has lost too much of its crown the leafy head that is vital for survival. It will probably not be able to grow enough new branches and leaves to provide needed nourishment, and will never be able to regain its former beautiful shape.

Hopeless Case: About all that’s left of this tree is its trunk. The few remaining branches can’t provide enough foliage to enable the tree to make it through another growing season.

Farewell to a Friend: A rotten inner core in the trunk or structural weakness in branching patterns can cause a split trunk the tree equivalent of a heart attack. The wounds are too large to ever mend, and the tree has lost its sap lifeline between roots and leaves. This tree is all but dead.

Some of your trees may have damage that’s too close to call, or may have hidden damage. To help with such questions, a tree professional may be needed to help you decide what to do about your trees. Don’t hire just anyone who shows up at your door following a storm. Look for qualified arborists in the phone book or by visiting the Texas Chapter of the International Society of Arboriculture website at http://www.trees-isa.org/. The National Arbor Day Foundation has helpful hints on their website at http://www.arborday.org/.

(Artwork provided by National Arbor Day Illustrations)

HOMEOWNERS NEED TO CONTACT THEIR INSURANCE COMPANY Finally, homeowners should be reminded to contact their insurance agent concerning the loss of shade trees -- pines or hardwoods -- or property damage caused by fallen limbs or trees. WHAT ABOUT BMPs AND SALVAGING TIMBER DAMAGED BY RITA? To protect water quality, Texas voluntary Best Management Practices (BMPs) should be

followed for all forestry operations, including salvage of storm-damaged timber. One very important BMP is to leave a strip of trees, called a streamside management zone (SMZ), along creeks and streams to act as a filter to water that will eventually enter the water course. High winds can cause considerable damage in SMZs and Hurricane Rita was no exception. The Texas Forest Service BMP coordinator prepared the following information concerning timber damage and BMPs. Read more about the subject at:

Best Management Practices Need To Be Applied When Salvaging Timber Damaged By Hurricane Rita EXOTIC INVASIVE PLANTS Another consideration related to storm-damaged timber is exotic invasive species. At least two alien plants that have become established in parts of East Texas may present additional concern following Hurricane Rita. Chinese tallow (Triadica sebifera) is well established in most East Texas counties. Japanese climbing fern (Lygodium jajponicum) is not as wide spread as Chinese tallow, but is spreading. Both plants are known to invade disturbed sites that are open to abundant sun light. The areas where timber stands were heavily damaged in southeast Texas will be especially vulnerable to invasion by Chinese tallow. Fire and herbicides will slow the spread and invasion of both of these species, but repeated treatments are required for complete control. INFORMATION ON STORING LOGS UNDER A WATER SPRINKLING SYSTEM Following Hurricane Hugo, which made landfall on the South Carolina coast near Charleston in 1989, a detailed study of long-term storage of logs under several water sprinkling regimes was conducted. The details of that report can be accessed at the following internet site: http://www.alaforestry.org/ivan/Publications/water_storage.pdf The abstract of that report is printed below for your convenience. EFFECTIVENESS OF WATER SPRINKLING FOR LONG-TERM STORAGE OF HURRICANE-DOWNED PINE TIMBER John R. Syme and Joseph R. Saucier Abstract--Loblolly pine sawlogs were stored under water sprinklers for a two-year period to determine the effectiveness of different sprinkling schedules on preventing infestation by insects and fungi. One hundred-twenty freshly-harvested test logs were selected from the same timber tract for the project. One-half of the logs were placed under water sprinklers (4 sprinkling schedules -- intermittent light and heavy and continuous light and heavy) immediately after harvest, while the other half were dry-stored from one to six months and then placed in the sprinkled decks. The test logs were stored in four separate sprinkled decks each with a different sprinkling schedule. The test logs were sampled periodically to determine moisture content, presence of fungi and insects, and change in mechanical properties. At the end of the two-year sprinkling period, the test logs were processed in a sawmill and veneer plant to determine the extent of degradation by fungi and insects. The continuous-heavy sprinkling schedule (4 inches of water per 24-hour

period; intermittent light sprinkling was 0.7 inches of water per 24-hour period) afforded the best protection to the logs of the four sprinkling schedules; there was no visible evidence of blue stain fungus, pine sawyers, or ambrosia beetles after two years of sprinkler storage. Logs in decks with other sprinkling schedules with lower water volumes showed various amounts of fungal and insect degradation, relative to the volumes of water applied. Some mechanical properties appeared to be affected by long-term sprinkling: tangential toughness was significantly lower at the end of the test period, while modulus of rupture, modulus of elasticity, and radial toughness were not reduced by a significant amount. The logs which were dry-stored prior to sprinkling, became infested with fungi and insects during the second month of dry-storage, and were heavily infested by the fourth month. COMPRESSION WOOD, LEANING TREES AND OTHER RELATED ISSUES Again we can learn from the experiences of Hurricane Hugo. Long-term studies of the effects of Hugo on wood properties of loblolly pine 10 years following the event were documented. It was assumed that 10% was the maximum allowable amount of compression wood that would be acceptable for normal wood product yield. Based on that assumption, the following conclusions were found.

1. Trees of any age at the time of the storm and with a lean greater than 45º should be harvested and/or replanted the next planting season.

2. Trees that were 4-6 years old at the time of the storm and had a lean greater than 35º should be replanted the next planting season.

3. Trees 8 years and older at the time of the storm with a lean greater than 25º should be harvested and the site replanted the next planting season.

4. Annual growth decreases significantly in trees with lean greater than 25º. 5. The proportion of stem compression wood increased significantly with tree age and

with lean greater than 25º. 6. Initial angle of lean does not directly impact chip quality. However, there is an

indirect affect because increasing angles of lean decreases diameter growth over time.

7. Any trees with less than 25º of lean should recover. 8. Trees less than 4 years of age and with less than 45º of lean should recover.

IMPACT OF RITA ON FOREST-RELATED VALUES AND RESOURCES In addition to direct damage to trees and the associated loss of valuable timber, other related resources have been severely affected. These include: Watersheds -- Tons of debris and fallen trees are impeding the flows of streams and small rivers, and thus degrading aquatic habitats. Further, the storm may have dumped chemicals, bacteria, and other pollutants into waterways. Wildlife Habitat -- With nearly 800,000 acres of forestland damaged, many nesting sites and habitats relied on by wildlife species have been destroyed and their food sources diminished. This will have a dramatic effect on hunting and fishing and the economies that rely on this revenue. In addition to game animals, many of the region’s endangered and threatened species, such as the red-cockaded woodpecker, have experienced a reduction in vital habitat.

Insects, Disease, Wildfire, and Invasive Species -- As time lapses, the dead trees will dry out and create extreme amounts of wildfire fuel, will provide food for tree-consuming insects, and will become suitable hosts for blue stain and decay fungi. It is critical that trees be harvested quickly to reduce fuels to mitigate the risk of wildfire and reduce insect and disease damage. Damaged forests are highly susceptible to invasive species, like Chinese tallow and Japanese climbing fern, which often rapidly colonize disturbed forest sites. HAP October 18, 2005