Rubber Sidewalks in Vancouver

The Hough neighborhood in Vancouver has recently switched to rubber sidewalks to solve the problem of sidewalk uplift from their large, old trees. Sidewalk uplift causes frequent, costly repairs and can be a tripping hazard. The co-chair for the Hough Neighborhood Association, Melissa Tiefenthaler, started looking at the rubber sidewalk option after the topic of sidewalk repair kept cropping up during neighborhood discussions.

Tiefenthaler applied for and received a grant to help pay for a demonstration project on one of Hough’s streets. She said the grant was approved because one of the benefits to keeping the trees is their calming effect on drivers – who usually slow down from a perceived effect that the street is narrower than it actually is.

Another benefit to the rubber sidewalks is decreasing storm runoff. This is because the recycled material in the sidewalks allows nearly 98 inches of rainwater to seep into the ground beneath the sidewalk. This water absorption allows tree roots to grow more deeply, reducing the risk of cracking or upheaval. These sidewalks also can be easily removed to prune tree roots and switch out one block of the sidewalk, instead of replacing an entire sidewalk.

With the new sidewalk in place, the city is watching to see how it holds up over time. In the long run, the city may make the rubber a standard sidewalk material.


Saving 350-Year-Old Bur Oak

John Sam Williamson from Missouri has been working to save a 350-year-old bur oak, probably the largest of its kind, by hauling 1,600 gallons of water to the tree each week. Missouri has had one of its hottest summers on record, with 99.29 percent of the state in extreme drought or worse. Williamson gets his water from the Missouri River and he told the Columbia Daily Tribune that he plans on watering the tree weekly for the next month or so. He hopes his efforts will keep the drought from killing the tree.

Even with his efforts, Williamson said that the bur oak has been showing signs of stress. “The leaves are beginning to curl up a little bit, and they have turned kind of brown. I think it has aborted a lot of the acorns. And the leaves turn upside down to keep from losing moisture,” he said.


The Seedpods of the Invasive Australian Blackwood

The Australian Blackwood (in the Mimosa family) is cultivated in a range from California to Chili, but in most of these areas, the tree has spread further than it was originally intended, making it an invasive species. The dispersal of the seeds of the tree is largely responsible for its ability to spread into new areas. The seedpods are contained in long, thin ribbon-like beans that are coral colored. Once the beans dry, they split and the seeds are projected in many directions.

In both Australia and South Africa, birds are attracted to the reddish-orange seed stalk, called an aril, which they consume – thus dispersing the seed widely throughout the birds’ habitat. South Africa has declared the Australian Blackwood a noxious weed species and has been seeking ways to control it. Presently, it has introduced a seed-feeding weevil to counteract its spread.

Ants are also attracted to the aril because it is rich in protein. The ants eat the arils and discard the seeds – usually in the nest or on a rubbish heap – where they are in a good environment for future germination. They can have a long dormancy. The seed has a hard coating for bushfire germination and may be viable for up to 50 years, while the tree itself has a lifespan of over 100 years, so it can produce many seeds during its lifetime.


Town Plans Final Sidewalk Repairs Before Homeowners are Responsible

Last year the town of Robbinsville, New Jersey, adopted an ordinance that makes sidewalk maintenance the homeowner’s responsibility, but the town is fixing the sidewalks one last time that are already a problem. This is because the town is worried about the possibility of trip-and-fall lawsuits caused by sidewalk uplift. To fix the sidewalks, the town has asked the homeowners to decide if they want a smaller caliber tree to replace trees that have roots that are causing uplift, or if they want to have the roots shaved on the mature trees before sidewalk maintenance is done. If residents don’t decide, the town will decide for them. Either way, if the newly planted tree or the root-shaved mature tree dies within the year, the town will replace the tree. After that, the tree and sidewalk are the homeowner’s responsibility.

It is estimated that there are more than 3,100 yards of uneven sidewalks in 15 developments in town. With the situation being different in every development, the two areas with the worst problems will be addressed first. In many areas, yard trees were planted too close to the sidewalk by developers. In other uplift cases, the wrong type of tree was selected as a sidewalk tree and planted in the narrow strip of land between the sidewalk and the street. The hope is that as each area is worked on, lessons learned will be used to more smoothly work on new areas. “We’re looking forward to moving forward,” said Council President Ron Witt. “Any lessons learned in the first two developments will apply to the next phase, and, hopefully, after that we’ll be working like a fine oiled-machine.”


Tree Roots Damage May Cause Plumbing Problems

Plumbing and underground building foundations may be slowly sustaining damage from tree root systems in the landscape. Roots can burrow into minute cracks in pipes and foundations, but not all trees and shrubs have root systems that are as likely to cause problems. Many problems can be avoided if the tree or shrub is given enough unobstructed room underground to grow out.

There are a few trees and shrubs that have special habitat needs, which will reduce the impact they have on pipes and foundations if these needs are addressed. The weeping willow is one. It needs a very rich and moist habitat and will aggressively seek this out if it isn’t planted in a spot that meets these needs. Magnolia trees have very strong rope-like roots that grow close to the surface and can cause foundation and pipe damage. Poplar trees have an extremely invasive root system, and their roots are able to grow two to three times the height of the tree. Birch trees also have a root system that grows two to three times the height of the tree.



Village Considers Replacement Trees

Yellow Springs, Ohio, has been considering the best replacement trees on a street where power lines are being buried and the existing Bradford pear tree roots will be cut. The Bradford pear trees are already severely topped to keep them from impacting the power lines they are under, and the trees are about 35 years old. “Even if you leave them in [after the sidewalk construction], you’re going to lose them in a year or two anyway,” said urban forester Wendi Ban Buren. Burying the lines will allow newly planted trees to grow to their natural height without the need for topping.

Bradford pear trees are no longer recommended as a landscaping choice, so the discussion has centered on what other choices are good for street trees. Native trees have been considered, but they usually do better with space to grow their roots, rich soil, and plenty of water. Instead, street trees need to be able to survive in a 5 x 5 foot tree pit, have deep root systems to keep from impacting nearby foundations, and be fruitless. Thornless honey locust, male gingko, berryless sweet gum, state street maple, lace bark elm, columnar oaks, linden, London plane, and red spire pear are all possible options.

Yellow Springs has no formal landscaping plan, so it needs to work with the Yellow Springs Tree Committee, which has planted 2000 trees on public property in the last 30 years. Village Manager Laura Curliss is working to establish a working relationship with the Tree Committee. ‘I’d like to work with the Tree Committee on a placement plan for trees in the future,” said Curliss.

Trees Cut and Sidewalks Repaired in Napa

Napa California has been working on repairing sidewalks in a two-block area that tree roots have uplifted. At an uplifted sidewalk on Montgomery Street, a pedestrian had tripped, so city crews reviewed the sidewalks and trees in the area. What they found was that there were many instances of uplifted sidewalks due to tree roots. Speaking of the spot of the tripping incident, Parks Superintendent Dave Perazzo said, “There was significant sidewalk lift at this location due to tree roots. Access to the home’s driveway was impacted as well as drainage from their property.”

Once it was confirmed that trees were the cause of the sidewalk deterioration, the trees in the area were cut down. Crews first examined the roots and trees to see if shaving or grinding roots would be possible to save the trees. Unfortunately, some of the trees were found to be decayed or hollow, and the branch attachments would probably become public safety hazards, as the trees grew larger. It was also found that 25% of the roots would have to be removed for most of the trees in order to complete the sidewalk repair – and this would cause a problem in tree stability.

Once the sidewalks are repaired, replacement trees, which neighbors were able to have a choice in, will be planted.

Whitefly: Attacking Plants and Leaving a Sticky Mess

Fort Lauderdale residents are noticing an increasingly pervasive nuisance pest in the rugose spiraling whitefly. These pests have invaded South Florida, originally spotted in 2009 in Miami-Dade. The pest lays eggs in a spiral pattern on leaves. When the eggs hatch, the flies feed off leaves and then secrete a sticky goo that covers leaves and anything below where the insects are. If the goo isn’t cleaned up, sooty mold forms.

The whitefly infestations have been observed to spread very quickly. One tree nursery and mulch manufacturer noticed that the 30-acre farm was totally infested. “I’ve never seen anything infect anything so quickly. You blink and all of a sudden your entire palm tree farm is infested,” said Dave Tomlinson, vice president of Amerigrow Recycling.

Michael Orfanedes, with the University of Florida and Broward County Extension Education commented, “It’s a nuisance of historical proportions. The whiteflies may disfigure [trees] and even potentially weaken them, but people need to be careful not to overact. The most significant problem to date is the nuisance factor, which is considerable and extensive.”

Whitefly infestations can be controlled using natural predators like Lady Beetles and by using natural soaps and spraying with a strong stream of water, or with various pesticides. There are three types of whitefly currently found in Florida: The ficus whitefly, the rugose spiraling whitefly, and the Bondar’s nesting whitefly.

Vacationing Couple Sues After Branch Falls on Them

Russell Narahara and his wife Beverly were vacationing in Waikiki when an eight-foot long banyan tree limb dropped on them while shopping. The couple sustained serious injuries. Beverly suffered a fractured skull and large cut on her head while Russell suffered a multiple-fractured hip. Russell has been hospitalized for four months in California due to his injuries, with no known release date.

The Narahara’s are suing the owners of the International Marketplace, where the accident took place, for negligence. Their attorney, Wayne Kekina, remarked, “Queen Emma Land Company needlessly endangered the safety of the public by failing to exercise reasonable care in monitoring and maintaining this banyan tree.” Kekina also reported that the tree is in a special registry, which requires a city permit for trimming. The last permit to trim the tree was issued in 2010, and that the limb was dead for at least two years.

The eight-foot limb was brought down during high winds. The limb was roughly three inches in diameter and fell more than eighty feet before it struck the couple. Kekina remarked that the tree should have been trimmed at least annually because it is located in a marketplace that is consistently crowded with people.

Drought Causes Tree Death and Limbs to Fall

Tyler State Park in East Texas has seen an increase in trees dying, due to drought in the region. Although more trees are dying, the state park says that it has been difficult keeping up with the necessary tree maintenance and removal because the state legislature took away some of their funding this year. An estimated 250 dying trees have been cut down in the park from about April through June to keep campers safe.

One tree that was not cut in time dropped a large limb onto an RV in the park. Neal Williams, his wife, and two grandsons were asleep in the RV at the time the branch fell. Although they were uninjured, the RV suffered minor damage. Williams and park officials were surprised that the limb fell in calm weather from what appeared to be a healthy tree.

Tyler State Park Superintendent, Bill Smart, says, “Since most of the trees die in winter, we don’t know until spring when the trees were supposed to come back and out, and they weren’t coming back out.” Smart warns that although they are doing the best they can, they need people to be aware of the condition of the trees and of the possibility of limbs falling.